JP2012131894A - Electrically conductive ink composition and electric conduction part produced using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrically conductive ink composition formable of the inside of an electric conduction part with few voids and high film density and formable of the electric conduction part at a temperature at which an organic base material can be used, and an electric conduction part produced using the same.SOLUTION: The electrically conductive ink composition comprises a metal powder, a coordinating compound, and copper formate particles, wherein the metal powder comprises a metal powder in which an average particle size ratio of metal particles (B) to metal particles (A) is 0.10-0.45. The electric conduction part is produced by applying or filling the ink composition on or into a base material and heat-treating the base material.

Description

  The present invention relates to a conductive ink composition and an electrical conduction part produced using the same. The conductive ink of the present invention can be suitably used as a circuit pattern forming material for a wiring board in the electronics field, and has good conductivity and high film density by using the conductive ink composition of the present invention. An electrically conducting portion can be obtained.

  In recent years, from the viewpoint of cost saving and low environmental load, technology that prints conductive ink in a desired pattern by a printing method such as screen printing and forms electrically conductive parts such as wirings and electrodes on a circuit board has attracted attention. Collecting.

  As the conductive ink, a metal paste obtained by pasting metal particles has been studied. A metal paste is generally a paste made by mixing metal particles, a binder resin, and a solvent. The metal particles are brought into physical contact with each other by curing shrinkage of the binder resin, etc. (See, for example, Patent Document 1). However, since such metal paste generally uses copper particles having a particle size of about 10 to 100 μm, there is a problem that there are many voids inside the formed electrically conductive portion and the film density is low. there were. When the film density is low, not only the resistance is high, but also water and oxygen present in the atmosphere are likely to diffuse through the conductor, and the metal particles that form the electrical conduction site are oxidized or the diffusion phenomenon causes the diffusion of metal ions. And grain growth can cause a circuit short. Here, electromigration is a phenomenon in which a metal component (for example, a metal used for a wiring or an electrode) moves across or inside a non-metallic medium (for example, an insulator) due to the influence of an electric field.

  In view of this, studies have been made to improve the film density of the electrically conductive portion.

For example, a conductive paste mainly composed of metal powder, glass frit, and an organic vehicle, wherein the metal powder is substantially spherical particles having an average primary particle diameter (D _A ) of 0.5 to 10 μm ( A), substantially spherical particles (B) having an average primary particle size (D _B ) of 0.1 μm or more and less than (D _A × 0.25) μm, and an average primary particle size of 50 nm The following substantially spherical particles (C) are the main components, and the blending amount of the glass frit is 0.1% by weight or more and 15% by weight or less with respect to the total value of the glass frit and the metal powder. Conductive pastes have been proposed. (For example, refer to Patent Document 2).

  In the method of Patent Document 2, three kinds of spherical particles are combined, the gap between the closely packed spherical particles (A) having a large average particle diameter is filled with the spherical particles (B) having a small particle diameter, and the spherical particles (A ) And (B) are filled with spherical particles (C) having a smaller particle size to improve the packing density and achieve high conductivity. However, in this conductive paste, since the temperature required for the heat treatment is 450 ° C. or higher, the applicable base materials are limited, and it is particularly difficult to adapt to organic base materials.

  On the other hand, as a method for forming an electrically conductive portion having a high film density, a method is proposed in which metal particles are applied to a substrate to form a metal particle layer, and then the obtained base material is further electrolessly copper-plated. (For example, refer to Patent Document 3). In this method, the metal particles applied to the substrate serve as a catalyst, and copper plating proceeds efficiently.

  However, in such a method, the number of steps related to the formation of the electrically conductive portion is as large as in the conventional plating method, and it is possible to take advantage of the advantage of using conductive ink such as resource saving, low cost, and low environmental load. Can not.

  As described above, none of the conventional methods can be said to be sufficient, and further studies have been demanded for industrial practical use. That is, a conductive ink composition capable of forming an electrically conductive portion with a small internal void and high film density, and capable of forming an electrically conductive portion at a temperature at which an organic substrate can be used, and using the same The development of manufactured electrical conduction sites has been desired.

JP-A-1-167385 JP 2006-196246 A JP 2006-225712 A

  The present invention has been made in view of the above-described background art, and an object of the present invention is to provide an electrically conductive ink composition for forming an electrically conductive portion with less internal voids and high film density. An object of the present invention is to provide a conductive ink composition capable of forming a part and forming an electrically conductive part at a temperature at which an organic substrate can be used, and an electrically conductive part manufactured using the same.

  In order to solve the above-mentioned problems, the present inventors have conducted extensive studies, and as a result, a conductive ink composition containing a metal powder, a coordination compound, and copper formate particles, wherein the metal powder has an average The present inventors have found a conductive ink composition comprising a metal powder having a particle size ratio in the range of metal particles (B) / metal particles (A) = 0.10 to 0.45 times. It has been found that this conductive ink composition can form an electrically conductive portion having a small internal void and a high film density, and can be formed at a temperature at which an organic substrate can be used. The present invention has been completed.

That is, the present invention relates to a conductive ink composition as shown below, and an electrically conductive portion produced using the same.
[1] A conductive ink composition containing a metal powder, a coordinating compound, and copper formate particles, wherein the metal powder has an average particle size ratio of metal particles (B) / metal particles (A) = 0. A conductive ink composition comprising a metal powder in a range of 10 to 0.45 times.
[2] The metal particles (A) and / or metal particles (B) are selected from the group consisting of gold particles, silver particles, copper particles, platinum particles, palladium particles, nickel particles, tin particles, and silver-coated copper particles. The conductive ink composition as described in [1] above, which contains at least one kind.
[3] The average particle size of the metal particles (A) is in the range of 0.1 to 10 μm, and the average particle size of the metal particles (B) is in the range of 0.01 to 4.5 μm. The conductive ink composition according to the above [1] or [2].
[4] The weight concentration of the metal particles (A) is in the range of 70 to 99% by weight and the weight concentration of the metal particles (B) is in the range of 1 to 30% by weight with respect to the total amount of the metal powder. The conductive ink composition according to any one of [1] to [3] above.
[5] The coordination compound is an aliphatic amine, an aromatic amine, a heterocyclic amine, an alkoxyamine represented by the following general formula (1), and an alkanol represented by the following general formula (2) or (3) The conductive ink composition as described in any one of [1] to [4] above, which is at least one selected from the group consisting of amines.

[R ₁ and R ₂ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R ₃ represents a straight-chain alkyl group having 1 to 6 carbon atoms, a branched or cyclic alkyl group having 3 to 6 carbon atoms. Represents a group, and X represents a methylene group or an ethylene group. ]

[R ₄ and R ₅ each independently represents a hydrogen atom, a methyl group, or an ethyl group, R ₆ and R ₇ each independently represent a hydrogen atom or a methyl group, and Y represents a methylene group or an ethylene group. Represents. ]

[R ₈ and R ₉ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and Z represents a methylene group or an ethylene group. ]
[6] The coordination compound is ethylamine, n-propylamine, i-propylamine, n-butylamine, n-pentylamine, n-hexylamine, cyclohexylamine, n-octylamine, 2-ethylhexylamine, n- Nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, piperidine, pyridine, piperazine, N-methylpiperazine, N-ethylpiperazine, homopiperazine, hexamethyleneimine, 2-methoxyethylamine, N, N-dimethyl 2-methoxyethylamine, 2-ethoxyethylamine, N, N-dimethyl-2-ethoxyethylamine, 2-n-propoxyethylamine, N, N-dimethyl-2-n-propoxyethylamine, 2-n-butoxyethylamine, N , N-dimethyl- -N-butoxyethylamine, 3-methoxypropylamine, N, N-dimethyl-3-methoxypropylamine, 3-ethoxypropylamine, N, N-dimethyl-3-ethoxypropylamine, 3-n-propoxypropylamine, N, N-dimethyl-3-n-propoxypropylamine, 3-n-butoxypropylamine, N, N-dimethyl-3-n-butoxypropylamine, ethanolamine, N-methylethanolamine, N, N-dimethyl Ethanolamine, N-ethylethanolamine, N, N-diethylethanolamine, 1,1-dimethyl-2-hydroxyethylamine, N, N-dimethyl-1,1-dimethyl-2-hydroxyethylamine, 3-hydroxypropylamine N, N-dimethyl-3-hydroxypropi Amine, 3-amino-1,2-propanediol, 3- (dimethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol, 4-amino-1,2-butanediol And at least one selected from the group consisting of 4- (dimethylamino) -1,2-butanediol. The conductive ink composition as described in any one of [1] to [5] above.
[7] The conductive ink composition as described in any one of [1] to [6], wherein the average particle diameter of the copper formate particles is in the range of 0.01 to 5 μm.
[8] The concentration of the metal powder is 1 to 98% by weight, the concentration of the coordinating compound is 1 to 80% by weight, and the concentration of the copper formate particles is 1 to 80% by weight with respect to the total amount of the conductive ink composition. The conductive ink composition as described in any one of [1] to [7] above, wherein
[9] The conductive ink composition as described in any one of [1] to [8] above, further comprising a diluent.
[10] The conductive ink composition as described in any one of [1] to [9] above, wherein the viscosity of the conductive ink composition is in the range of 1 to 1000 Pa · s.
[11] Electrically produced by applying or filling the conductive ink composition according to any one of [1] to [10] above to a base material, and subjecting the base material to a heat treatment. Conduction site.
[12] The base material is one or two or more composite base materials selected from the group consisting of resin, paper, glass, silicon-based semiconductor, compound semiconductor, metal oxide, metal nitride, and wood. The electrical conduction site according to [11] above, which is characterized by the following.
[13] The electrical conduction site according to [11] or [12] above, wherein the temperature of the heat treatment is in the range of 60 to 300 ° C.
[14] The electrically conductive portion according to any one of [11] to [13], wherein the heat treatment is performed in a non-oxidizing atmosphere.

  The present invention has the following effects.

  (1) The conductive ink composition of the present invention has a high film density at the electrically conductive portion formed after the heat treatment and is excellent in conductivity, and also has a conductive pattern or the like by a simple method such as coating, filling, or heating. Therefore, energy saving, low cost and low environmental load can be achieved, which is extremely useful industrially.

  The conductive ink composition of the present invention can form an electrically conductive portion at a temperature at which a resin can be used as a substrate, and is excellent in versatility.

  In addition, the conductive ink composition of the present invention contains copper formate particles as a conductor precursor, which becomes metallic copper, which is a component of the electrically conductive portion, so that the electrical conductivity having the excellent characteristics of copper. A site can be formed.

  Furthermore, the conductive ink composition of the present invention has a high metal concentration and does not require recoating for increasing the film thickness, or can reduce the number of times and is excellent in work efficiency. Moreover, since there is little influence of changes in viscosity and surface tension during heating after application, changes in the wiring width and shape after application and after heating are small, and dimensional accuracy is excellent.

  Furthermore, since the conductive ink composition of the present invention can be easily adjusted to a desired viscosity by containing a diluent as necessary, a pattern can be formed by a screen printing method.

  (2) The electrically conductive portion of the present invention uses the conductive ink composition of the present invention, so that a reducing atmosphere containing hydrogen is not required in the step of forming the electrically conductive portion, and an inert atmosphere such as nitrogen. Electrically conductive sites can be formed by heating underneath, which is excellent in safety.

  Moreover, the electrical conduction site of the present invention can be formed at a temperature at which a resin can be used as a base material, and is excellent in versatility.

  Furthermore, since the electrically conducting portion of the present invention has few internal voids and a high film density, it has low resistance and excellent oxidation resistance and migration resistance.

  The present invention is described in further detail below.

  The conductive ink composition of the present invention is a composition containing metal powder, a coordinating compound, and copper formate particles, wherein the metal powder has an average particle size ratio of metal particles (B) / metal particles (A). = A conductive ink composition comprising a metal powder in a range of 0.10 to 0.45 times.

  In the conductive ink composition of the present invention, the metal powder functions as a filler, exhibits conductivity by ohmic contact, suppresses changes in viscosity and surface tension during heating after coating, and heats during coating and heating. The shape change of the electrically conductive part after the treatment is reduced. Furthermore, the metal powder also serves as a catalyst for promoting reduction of copper ions contained in the copper formate particles when heat-treated, and as a result, the treatment temperature can be lowered and the treatment time can be shortened. .

  In the conductive ink composition of the present invention, the metal powder includes a metal powder having an average particle size ratio in the range of metal particles (B) / metal particles (A) = 0.10 to 0.45 times. And In this way, when two kinds of metal particles having different average particle diameters are combined, when an electrically conductive portion is formed, in the conductive film, metal particles having a small particle size (A) between large metal particles (A) ( B) is filled, and the gap between the metal particles (A) can be filled, and the packing density is improved as compared with the case where the metal particles (A) or the metal particles (B) are used singly.

  The average particle diameter of the metal particles (B) in the metal powder is in the range of 0.10 to 0.45 times the average particle diameter of the metal particles (A). When the particle size of the metal particles (B) is larger than 0.45 times the average particle size of the metal particles (A), the close-packed structure of the metal particles (A) is broken, and the packing density of the whole particles is low. Become. Moreover, when the particle size of the metal particles (B) is less than 0.1 times the average particle size of the metal particles (A), the particle size of the metal particles (B) is too small, and the gap between the metal particles (A) It cannot be completely filled and the conductivity is lowered.

  In the conductive ink composition of the present invention, the metal powder may contain one or more metal particles having different average particle diameters in addition to the metal particles (A) and / or the metal particles (B). In addition, as a measuring method of the average particle diameter of a metal particle (A) and / or a metal particle (B), a general measuring method can be used. For example, a transmission electron microscope (TEM), a field emission transmission electron microscope (FE-TEM), a field emission scanning electron microscope (FE-SEM), or the like can be used as appropriate. The value of the average particle diameter is measured using the above-mentioned apparatus, and three locations where the particle diameters are relatively uniform are selected from the observed field of view, and images are taken at the magnification most suitable for the particle size measurement. From each photograph, 100 particles that are considered to be present in the largest number are selected, the diameter thereof is measured with a ruler, and the particle size is calculated by dividing the measurement magnification. These values were obtained by arithmetic averaging.

  In the conductive ink composition of the present invention, the metal particles (A) and / or the metal particles (B) are not particularly limited, and examples thereof include gold particles, silver particles, copper particles, platinum particles, and palladium particles. And those containing at least one metal particle selected from the group consisting of nickel particles, tin particles, and silver-coated copper particles. These metal particles may be a simple substance or an alloy with another metal. Among these, at least one selected from the group consisting of silver particles, copper particles, and silver-coated copper particles is preferable in terms of cost, availability, and conductive performance. Here, the silver-coated copper particles represent copper particles whose surfaces are coated (coated) with silver.

  In the conductive ink composition of the present invention, metal particles other than these may be used as the metal particles (A) and / or the metal particles (B). It is desirable to use the above-mentioned metal particles because there is a possibility that the rate of reduction and precipitation from the copper formate particles to the metal copper may be reduced due to oxidation, or the catalytic ability being reduced or not being expressed.

  In the conductive ink composition of the present invention, when printing is performed by the screen printing method, the ink passes through the mesh and can be printed, and the activity of the metal surface becomes very high, and there is no possibility of being oxidized or dissolved. Therefore, the average particle diameter of the metal particles (A) is preferably in the range of 0.1 to 10 μm, and the average particle diameter of the metal particles (B) is preferably in the range of 0.01 to 4.5 μm.

  In the conductive ink composition of the present invention, the mixing ratio of the metal particles (A) and the metal particles (B) in the metal powder is such that the gap between the metal particles is sufficient without blocking the contact portion between the metal particles. Since it can be filled, it is preferable that the weight concentration of the metal particles (A) is in the range of 70 to 99% by weight and the weight concentration of the metal particles (B) is in the range of 1 to 30% by weight with respect to the total amount of the metal powder. .

  In the conductive ink composition of the present invention, the metal particles (A) and / or the metal particles (B) may be commercially available or synthesized by a known method, and are not particularly limited. Moreover, there is no limitation in particular as a shape of a metal particle, The thing of arbitrary shapes, such as spherical shape, scale shape, needle shape, and dendritic shape, can be used. As a known synthesis method, for example, mechanical pulverization method, atomization method, gas phase reduction method, CVD method, PVD method, electrolytic deposition method, chemical reduction method and the like are generally known. As a method for synthesizing silver-coated copper particles, for example, a method of plating silver on the copper particles themselves or a method of depositing silver salts such as silver nitrate mixed with copper particles is generally known.

  In the conductive ink composition of the present invention, the purity of the metal particles (A) and / or the metal particles (B) is not particularly limited. When the conductive thin film is too low in purity, the conductivity is low. 95% or more is preferable, and 99% or more is particularly preferable.

  In the conductive ink composition of the present invention, the metal powder can be easily prepared by mixing the above-described metal particles (A) and metal particles (B) at a desired mixing ratio. The mixing method can be carried out by a known method and is not particularly limited.

  In the conductive ink composition of the present invention, the coordination compound has an effect of improving the dispersibility of the metal powder and the copper formate particles and stabilizing the reduction reaction of the copper ions when forming the electrically conductive portion.

  The coordinating compound in the present invention is not particularly limited as long as it is a compound having a coordinating ability with respect to metal powder and / or copper formate particles. It is preferably at least one selected from the group consisting of a formula amine, an alkoxyamine represented by the following general formula (1), and an alkanolamine represented by the following general formula (2) or (3).

[R ₁ and R ₂ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R ₃ represents a straight-chain alkyl group having 1 to 6 carbon atoms, a branched or cyclic alkyl group having 3 to 6 carbon atoms. Represents a group, and X represents a methylene group or an ethylene group. ]

[R ₄ and R ₅ each independently represents a hydrogen atom, a methyl group, or an ethyl group, R ₆ and R ₇ each independently represent a hydrogen atom or a methyl group, and Y represents a methylene group or an ethylene group. Represents. ]

[R ₈ and R ₉ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and Z represents a methylene group or an ethylene group. ]
Examples of the aliphatic amine include ethylamine, n-propylamine, i-propylamine, n-butylamine, n-pentylamine, n-hexylamine, cyclohexylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine and the like are mentioned. Examples of the aromatic amine include piperidine and pyridine. Examples of the heterocyclic amine include piperazine, N-methylpiperazine, N. -Ethylpiperazine, homopiperazine, hexamethyleneimine and the like.

Examples of the linear alkyl group having 1 to 6 carbon atoms in R ₅ of the general formula (2) include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Examples of the branched alkyl group having 3 to 6 carbon atoms include i-propyl group, i-butyl group, sec-butyl group, t-butyl group, i-pentyl group, sec-pentyl group, t- Examples include a pentyl group, a neo-pentyl group, and an i-hexyl group. Examples of the cyclic alkyl group having 3 to 6 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

  Specific examples of the compound represented by the general formula (1) include 2-methoxyethylamine, N-methyl-2-methoxyethylamine, N, N-dimethyl-2-methoxyethylamine, N-ethyl-2-methoxyethylamine, N, N-diethyl-2-methoxyethylamine, 2-ethoxyethylamine, N-methyl-2-ethoxyethylamine, N, N-dimethyl-2-ethoxyethylamine, N-ethyl-2-ethoxyethylamine, N, N-diethyl 2-ethoxyethylamine, 2-n-propoxyethylamine, N-methyl-2-n-propoxyethylamine, N, N-dimethyl-2-n-propoxyethylamine, 2-n-butoxyethylamine, N-methyl-2- n-Butoxyethylamine, N, N-dimethyl-2-n-butoxye Ruamine, 3-methoxypropylamine, N-methyl-3-methoxypropylamine, N, N-dimethyl-3-methoxypropylamine, N-ethyl-3-methoxypropylamine, N, N-diethyl-3-methoxypropyl Amine, 3-ethoxypropylamine, N-methyl-3-ethoxypropylamine, N, N-dimethyl-3-ethoxypropylamine, N-ethyl-3-ethoxypropylamine, N, N-diethyl-3-ethoxypropyl Amine, 3-n-propoxypropylamine, N-methyl-3-n-propoxypropylamine, N, N-dimethyl-3-n-propoxypropylamine, 3-n-butoxypropylamine, N-methyl-3- n-butoxypropylamine, N, N-dimethyl-3-n-butoxypropylamine Etc. The.

  Specific examples of the compound represented by the general formula (2) include ethanolamine, N-methylethanolamine, N, N-dimethylethanolamine, N-ethylethanolamine, N, N-diethylethanolamine, 1,1. -Dimethyl-2-hydroxyethylamine, N-methyl-1,1-dimethyl-2-hydroxyethylamine, N, N-dimethyl-1,1-dimethyl-2-hydroxyethylamine, 3-hydroxypropylamine, N-methyl- Examples include 3-hydroxypropylamine, N, N-dimethyl-3-hydroxypropylamine, N-ethyl-3-hydroxypropylamine, N, N-diethyl-3-hydroxypropylamine, and the like.

  Specific examples of the compound represented by the general formula (3) include 3-amino-1,2-propanediol, 3- (methylamino) -1,2-propanediol, and 3- (dimethylamino) -1, 2-propanediol, 3- (ethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol, 4-amino-1,2-butanediol, 4- (methylamino)- 1,2-butanediol, 4- (dimethylamino) -1,2-butanediol, 4- (ethylamino) -1,2-butanediol, 4- (diethylamino) -1,2-butanediol and the like Can be mentioned.

  Among these, as the coordination compound, ethylamine, n-propylamine, i-propylamine, n-butylamine, n-pentylamine, n-hexylamine, cyclohexylamine, n-octylamine, 2-ethylhexylamine, n -Nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, piperidine, pyridine, piperazine, N-methylpiperazine, N-ethylpiperazine, homopiperazine, hexamethyleneimine, 2-methoxyethylamine, N, N- Dimethyl-2-methoxyethylamine, 2-ethoxyethylamine, N, N-dimethyl-2-ethoxyethylamine, 2-n-propoxyethylamine, N, N-dimethyl-2-n-propoxyethylamine, 2-n-butoxyethylamine, N, -Dimethyl-2-n-butoxyethylamine, 3-methoxypropylamine, N, N-dimethyl-3-methoxypropylamine, 3-ethoxypropylamine, N, N-dimethyl-3-ethoxypropylamine, 3-n- Propoxypropylamine, N, N-dimethyl-3-n-propoxypropylamine, 3-n-butoxypropylamine, N, N-dimethyl-3-n-butoxypropylamine, ethanolamine, N-methylethanolamine, N , N-dimethylethanolamine, N-ethylethanolamine, N, N-diethylethanolamine, 1,1-dimethyl-2-hydroxyethylamine, N, N-dimethyl-1,1-dimethyl-2-hydroxyethylamine, 3 -Hydroxypropylamine, N, N-dimethyl-3- Roxypropylamine, 3-amino-1,2-propanediol, 3- (dimethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol, 4-amino-1,2- Preferred are butanediol, 4- (dimethylamino) -1,2-butanediol, and more preferably n-butylamine, n-pentylamine, n-hexylamine, n-octylamine, 2-ethylhexylamine, n-decylamine. Piperidine, N-ethylpiperazine, homopiperazine, hexamethyleneimine, 2-methoxyethylamine, 2-ethoxyethylamine, 2-n-propoxyethylamine, 2-n-butoxyethylamine, 3-methoxypropylamine, 3-ethoxypropylamine 3-n-butoxypropylamine , Ethanolamine, N-methylethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, 1,1-dimethyl-2-hydroxyethylamine, 3-hydroxypropylamine, N, N-dimethyl-3 -Hydroxypropylamine, 3-amino-1,2-propanediol, 3- (dimethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol, etc., particularly preferably n -Octylamine, 2-ethylhexylamine, homopiperazine, hexamethyleneimine, 2-ethoxyethylamine, 2-n-butoxyethylamine, 3-methoxypropylamine, 3-n-butoxypropylamine, ethanolamine, N, N-dimethyl Ethanolamine, 1,1-dimethyl 2-hydroxyethylamine, 3- (dimethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol. These can be used alone or in combination of two or more.

  The conductive ink composition of the present invention may contain any coordinating compound other than those described above as long as it does not contradict the spirit of the present invention.

  In the conductive ink composition of the present invention, the coordinating compound may be a commercially available one or may be synthesized by a known method, and is not particularly limited. The purity of the coordination compound is not particularly limited, and is preferably 95% or more, particularly preferably 99% or more, considering use in the field of electronic materials.

  In the conductive ink composition of the present invention, the copper formate particles are reduced by the formic acid that is a counter anion of the copper ions contained in the copper formate particles, and the gap between the metal particles (A) and / or the metal particles (B). In addition to further increasing the film density of the electrically conductive portion formed and deposited as metallic copper, it plays a role of improving conductivity.

  In the conductive ink composition of the present invention, the copper formate particles are not particularly limited as long as they are copper salt particles having a copper ion as a cation species and formic acid as an anion species. For example, at least one selected from the group consisting of monovalent copper ions, divalent copper ions, and trivalent copper ions, and particles of copper salts made of formic acid can be given. Among these, from the viewpoint of stability and availability, copper salt particles composed of divalent copper ions and formic acid are preferable.

  In the conductive ink composition of the present invention, the purity of the copper formate particles is not particularly limited, and is preferably 95% or more and particularly preferably 99% or more from the viewpoint of imparting conductivity.

  In the conductive ink composition of the present invention, the average particle size of the copper formate particles is not particularly limited, and is preferably in the range of 1 nm or more and less than 10 μm. By setting the amount within this range, when dissolved, when reprecipitated, other particles are deposited as nuclei, and there is no risk of coarsening of the particles, and a conductive ink composition that can form patterns such as wiring by a printing method When it becomes difficult to adapt to an object or forms an electrically conductive part, it does not react completely to the inside of the particle, the reduction to metallic copper becomes insufficient, and the conductivity of the formed electrically conductive part There is no risk of adverse effects.

  In the conductive ink composition of the present invention, the copper formate particles may be commercially available or produced by a known method, and further, by mixing a compound containing copper ions and formic acid in the system. The formed one can be used without any limitation, and is not particularly limited.

  The method for producing the copper formate particles is not particularly limited. For example, a method of pulverizing a coarse powder of copper formate particles by mechanical pulverization, or a method of depositing copper formate particles from a solution containing copper ions and formic acid. Etc. Among these, the method of pulverizing the coarse powder of copper formate particles by mechanical pulverization is preferable because the reproducibility of the particle size is good and a large amount of solvent and large-scale equipment are not required.

  The mechanical pulverization is not particularly limited. For example, it may be dry or wet. Specifically, a ball mill, a bead mill, a sand mill, a jet mill, a cutter mill, a hammer mill, One or more of the group consisting of a vibration mill, a colloid mill, a roll mill, a mortar, and a stone mortar can be used. Among them, it is preferable to use a bead mill because fine particles can be obtained efficiently.

  In the present invention, as a method for measuring the average particle size of copper formate particles, a transmission electron microscope (TEM) or a scanning electron microscope (SEM) is used. Select three locations and shoot at the most suitable magnification for particle size measurement. From each photograph, 100 particles that seemed to be the most abundant were selected, the diameter was measured with a ruler, the particle size was calculated by dividing the measurement magnification, and these values were obtained by arithmetic averaging. .

  In the conductive ink composition of the present invention, the concentration of each component is not particularly limited. The concentration of the metal powder is 1 to 98% by weight and the concentration of the coordinating compound is 1 to 80% with respect to the total amount of the conductive ink composition. It is preferable that the concentration of the copper formate particles is in the range of 1% by weight to 80% by weight, particularly the concentration of the metal powder is 20 to 90% by weight, and the concentration of the coordinating compound is 1 to 50% by weight. And the concentration of the copper formate particles is preferably in the range of 1 to 50% by weight [however, the total amount of the metal powder, the coordination compound and the copper formate particles does not exceed 100% by weight. . ].

  By setting the concentration of the metal powder in the above range, when forming an electrically conductive portion with less metal content in the ink, it is not necessary to repeatedly apply and solidify in order to obtain a desired film thickness. There is nothing.

  Further, by making the concentration of the coordination compound in the above range, the copper particles and / or the copper formate particles are sufficiently dispersed, and the concentration of the metal in the total amount of the conductive ink composition is not lowered. The application amount of the conductive ink composition for obtaining an electrically conductive portion having a desired film thickness does not increase.

  Furthermore, by setting the concentration of the copper formate particles in the above range, an electrically conductive portion having a sufficient film thickness can be formed without reducing the amount of metallic copper generated from the copper formate particles, and the conductive ink composition. No increase in viscosity or solidification occurs.

  The conductive ink composition of the present invention may contain a diluent in addition to the above components.

  In the conductive ink composition of the present invention, the diluent can easily adjust the viscosity of the conductive ink composition to a desired viscosity by changing its concentration.

  In the conductive ink composition of the present invention, the diluent is not particularly limited as long as it does not react with the metal powder, the coordinating compound, and the copper formate particles. For example, alcohols, glycols, ethers, Examples thereof include at least one selected from the group consisting of esters, aliphatic hydrocarbons, and aromatic hydrocarbons.

  Examples of alcohols include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, sec-butyl alcohol, pentanol, hexanol, heptanol, octanol, cyclohexanol, and benzyl alcohol. , Terpineol and the like.

  Examples of glycols include ethylene glycol, propylene glycol, butylene glycol, pentanediol, diethylene glycol, dipropylene glycol, triethylene glycol, and tripropylene glycol.

  Examples of ethers include diethyl ether, diisobutyl ether, dibutyl ether, methyl t-butyl ether, methyl cyclohexyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, tetrahydrofuran, tetrahydropyran, 1 , 4-dioxane and the like.

  Examples of esters include methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyl propionate, and γ-butyrolactone.

  Examples of the aliphatic hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-undecane, n-dodecane, cyclohexane, decalin and the like. .

  Examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, n-propylbenzene, i-propylbenzene, n-butylbenzene, mesitylene, chlorobenzene, dichlorobenzene, and the like.

  Among these, from the viewpoint of cost and safety, it should be at least one selected from the group consisting of hexanol, terpineol, ethylene glycol, methyl-t-butyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, n-hexane, and γ-butyrolactone. preferable.

  In the conductive ink composition of the present invention, the diluent may be a commercially available one or may be synthesized by a known method.

  In the conductive ink composition of the present invention, the purity of the diluent is not particularly limited, and is preferably 95% or more, particularly preferably 99% or more, considering use in the field of electronic materials.

  In the conductive ink composition of the present invention, the concentration of the diluent is not particularly limited, and the conductive ink for obtaining an electrically conductive portion having a desired film thickness is reduced by reducing the copper concentration in the total amount of the conductive ink composition. Since the coating amount of the composition does not increase, the concentration of the diluent is preferably in the range of 1 to 90% by weight with respect to the total amount of the conductive ink composition.

  In the conductive ink composition of the present invention, the viscosity of the conductive ink composition may be appropriately adjusted according to a desired coating method, and is not particularly limited. When applying by screen printing and patterning, it is preferable to adjust to the range of 1-1000 Pa.s.

  Next, the electrical conduction site using the conductive ink composition of the present invention will be described.

  In the present invention, the “electrically conductive portion” means a portion having electrical continuity formed using the conductive ink composition of the present invention. For example, a conductive thin film, a wiring, an electrode, an electrical conduction part between both surfaces and / or multilayers through a through hole, a joint part having electrical conduction between a substrate and an object to be joined, and the like can be given.

  The electrically conducting portion of the present invention is produced by applying or filling the conductive ink composition of the present invention on a base material and heat-treating the base material. For example, after applying the conductive ink composition of the present invention on a substrate, heat treatment is performed to reduce copper ions contained in the copper formate particles, and the coordinating compound is volatilized and removed. An electrically conducting portion can be easily manufactured on the substrate.

  In the electrical conduction site of the present invention, a known material can be used as the substrate, and there is no particular limitation. For example, resin, paper, glass, silicon-based semiconductor, compound semiconductor, metal oxide, metal nitride 1 type, 2 types or more, or 2 types or more composite base materials which consist of wood etc. are mentioned.

  Specific examples of the resin include low density polyethylene resin, high density polyethylene resin, ABS resin (acrylonitrile-butadiene-styrene copolymer resin), acrylic resin, styrene resin, vinyl chloride resin, polyester resin, phenol resin, epoxy Examples thereof include resins, polyacetal resins, polysulfone resins, polyimide resins, polyetherimide resins, polyether ketone resins, and cellulose derivatives.

  Specifically, for example, non-coated printing paper, fine-coated printing paper, coated printing paper (art paper, coated paper), special printing paper, copy paper (PPC paper), unexposed packaging paper ( Examples include heavy-duty kraft paper and double-kraft paper), bleached wrapping paper (bleached kraft paper, pure white roll paper), coated balls, chip balls, cardboard and the like.

  Specific examples of the glass include soda glass, borosilicate glass, silica glass, and quartz glass.

  Specific examples of the silicon-based semiconductor include single crystal silicon, polycrystalline silicon, amorphous silicon, and polysilicon.

  Specific examples of the compound semiconductor include CdS, CdTe, GaAs, and the like.

  Specific examples of the metal oxide include alumina, sapphire, zirconia, titania, yttrium oxide, indium oxide, ITO (indium tin oxide), IZO (indium zinc oxide), nesa (tin oxide), ATO ( Examples include antimony-doped tin oxide), fluorine-doped tin oxide, zinc oxide, AZO (aluminum-doped zinc oxide), and gallium-doped zinc oxide.

  Specific examples of the metal nitride include aluminum nitride and silicon nitride.

  Moreover, as a composite base material, specifically, for example, paper-resin composite base material such as paper-phenol resin, paper-epoxy resin, paper-polyester resin, glass cloth-epoxy resin, glass cloth-polyimide system. Examples thereof include glass cloth-resin composite base materials such as resin and glass cloth-fluorine resin.

  In the electrically conductive portion of the present invention, the heat treatment is preferably performed in a non-oxidizing atmosphere. Examples of the non-oxidizing atmosphere include helium, nitrogen, and argon. Among these, it is preferable to use nitrogen because it is inexpensive. Further, the non-oxidizing atmosphere may contain oxygen as long as it does not significantly affect the oxidation of the formed electrical conduction site, and its concentration is preferably 5000 ppm or less, particularly preferably 500 ppm or less. .

  In the electrically conducting part of the present invention, the temperature of the heat treatment is not particularly limited as long as the copper ion in the copper formate particles is reduced and the coordination compound is volatilized and removed, and the copper formate particles are not particularly limited. The reduction of the copper ions therein proceeds completely, the coordinating compound does not remain, and an organic base material can be used. Therefore, the range of 60 to 300 ° C. is preferable, and the range of 80 to 200 ° C. is particularly preferable.

  Moreover, what is necessary is just to select the time of heat processing suitably with temperature or the electroconductivity desired, and when the heating temperature of about 200 degreeC is set, it is about 10 to 60 minutes normally.

  The method for applying the conductive ink composition of the present invention to the substrate in the electrically conductive portion of the present invention can be performed by a known method, and is not particularly limited. For example, screen printing method, dip coating method , Spray coating method, spin coating method, ink jet method, dispenser coating method and the like. There is no problem even if the shape of application is planar or dot-like, and there is no particular limitation. The coating amount for applying the conductive ink composition to the substrate may be appropriately adjusted according to the desired film thickness of the electrically conductive part, and the film thickness of the conductive ink composition after drying is 0.01 to The range of 5000 μm is preferable, and the coating may be particularly preferably performed in the range of 0.1 to 1000 μm.

  The electrical conduction site of the present invention can be used as part of a process for producing various industrial products, and an industrial product having an electrical conduction site partially or entirely manufactured by the electrical conduction site of the present invention. Can be obtained.

  There are no particular limitations on the industrial product having an electrically conductive part that is partially or wholly produced by the electrically conductive part of the present invention, for example, an image display device such as an organic electroluminescence panel, a plasma display panel, or a liquid crystal panel; Light emitting devices such as LED (Light Emitting Diode) light emitting devices and organic electroluminescence light emitting devices; Circuits such as one-layer (single-sided) printed wiring boards, two-layer (double-sided) printed wiring boards, multilayer printed wiring boards, and flexible printed wiring boards Substrates; capacitors such as multilayer capacitors and solid electrolytic capacitors; solar cells such as silicon solar cells, compound semiconductor solar cells, dye-sensitized solar cells, and organic semiconductor solar cells; lithium secondary batteries, nickel-hydrogen secondary Secondary batteries such as batteries; radio wave type recognition tags; electromagnetic waves A shielding shield etc. are mentioned.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not construed as being limited to these examples.

  The average particle diameter of the particles is selected at random from three fields of view using a transmission electron microscope (TEM) or a scanning electron microscope (SEM) according to the particle size, and is 10,000. Take a picture at an arbitrary magnification in the range of ~ 1,000,000 times, select a total of 100 particles from each photo, measure the diameter with a ruler, calculate the particle size by dividing the measurement magnification, These values were obtained by arithmetic averaging. TEM manufactured by JEOL Ltd., trade name: JEM-2000FX, and SEM used by JEOL Ltd., trade name: JSM T220A.

  Furthermore, the viscosity of the conductive ink composition was measured at a measurement temperature of 30 ° C. using a rheometer (trade name: AR Rheometer AR2000ex, manufactured by TA Instruments).

[Reference Example 1] Preparation of copper formate particles.
To 40 g of ethanol, 2.24 g of copper formate particle powder (primary average particle diameter 21 μm) and 150 g of zirconia beads (made by Nikkato Co., Ltd., trade name: YZT ball, size: Φ0.1 mm) were added and connected to a stirring motor. Using a stirring blade, the mixture was stirred for 12 hours at a peripheral speed of 10 m / sec and pulverized.

  Next, this slurry-like mixture was passed through a sieve having an opening of 0.075 mm and further washed with 160 g of ethanol to separate zirconia beads to obtain a copper formate particle dispersion.

  This copper formate particle dispersion was observed with an SEM and the average particle size was determined to be 210 nm. Next, this copper formate particle dispersion was distilled off ethanol and excess water at a temperature not exceeding 60 ° C. under reduced pressure to obtain 1.68 g of powder of copper formate particles.

[Example 1] Metal powder containing two types of silver particles having different average particle diameters (average particle diameter ratio metal particles (B) / metal particles (A) = 0.30), n-octylamine, and copper formate particles Preparation of a conductive ink composition containing
To 10 g of tetrahydrofuran, 0.9 g of silver particles (Silver Powder made by Alfa Aesar) (metal particles (A)) having an average particle size of 2.32 μm and silver particles having an average particle size of 0.69 μm (Silver made by Alfa Aesar) Powder) (metal particles (B)) 0.1 g (metal powder: 90% by weight of metal particles A, 10% by weight of metal particles B), and n-octylamine (coordinating compound), which is an aliphatic amine, was added to 0.1%. 23 g and 0.22 g of the copper formate particles (primary average particle diameter 210 nm) obtained in Reference Example 1 were added and sufficiently kneaded until completely dispersed in a mortar. The slurry-like mixture was subjected to distillation of tetrahydrofuran and excess water at 40 ° C. under reduced pressure to obtain a paste-like conductive ink composition (metal powder: 69.0% by weight, n-octylamine: 15.8 wt%, copper formate particles: 15.2 wt%). The viscosity of the obtained conductive ink composition was 178 Pa · s (hereinafter, for the sake of brevity, this is referred to as “conductive ink A”).

[Example 2] Conductivity containing metal powder containing copper particles and silver particles (average particle size ratio metal particles (B) / metal particles (A) = 0.38), hexamethyleneimine, and copper formate particles Preparation of ink composition.
To 10 g of tetrahydrofuran, 0.8 g of copper particles (copper powder made by Alfa Aesar) (metal particles (A)) having an average particle size of 2.49 μm and silver particles having an average particle size of 0.95 μm (Silver made by Alfa Aesar) 0.2 g (metal powder: 80% by weight of particle A, 20% by weight of metal particle B) and 0.14 g of hexamethyleneimine (coordinating compound) which is a heterocyclic amine. And 0.13 g of the copper formate particles (primary average particle diameter 210 nm) obtained in Reference Example 1 were added, and the mixture was sufficiently kneaded until completely dispersed in a mortar. From this slurry-like mixture, tetrahydrofuran and excess water were distilled off at 40 ° C. under reduced pressure to prepare a paste-like conductive ink composition. The resulting conductive ink composition (metal powder: 78.8% by weight, hexamethyleneimine: 11.0% by weight, copper formate particles: 10.2% by weight) had a viscosity of 189 Pa · s (hereinafter referred to as “the following”). For the sake of brevity, this is referred to as “conductive ink B”).

Example 3 Metal powder containing silver particles and silver-coated copper particles (average particle size ratio metal particles (B) / metal particles (A) = 0.42), 3-n-butoxypropylamine, copper formate particles Preparation of conductive ink composition containing ethylene glycol.
To 10 g of tetrahydrofuran, 0.75 g of silver particles (Silver Powder manufactured by Alfa Aesar) (metal particles (A)) having an average particle diameter of 2.32 μm and silver-coated copper particles having an average particle diameter of 0.98 μm (Mitsui Metals Co., Ltd.) 0.25 g (metal powder: 75% by weight of particle A, 25% by weight of metal particle B) manufactured by Ag / wet copper powder) (metal particles (B)), which is an alkoxyamine represented by the general formula (1) 3- Add 0.36 g of n-butoxypropylamine (coordinating compound), 0.3 g of copper formate particles (primary average particle diameter 210 nm) obtained in Reference Example 1, 0.2 g of ethylene glycol as a diluent, The mixture was sufficiently kneaded until it was completely dispersed in a mortar. This slurry-like mixture was distilled under reduced pressure at 40 ° C. to distill off tetrahydrofuran and excess water, thereby obtaining a paste-like conductive ink composition (metal powder: 53.8% by weight, 3-n-butoxy. Propylamine: 19.3% by weight, copper formate particles: 16.1% by weight, ethylene glycol: 10.8% by weight). The viscosity of the obtained conductive ink composition was 98 Pa · s (hereinafter, for the sake of brevity, this is referred to as “conductive ink C”).

Example 4 Metal powder containing copper particles and silver-coated copper particles (average particle size ratio metal particles (B) / metal particles (A) = 0.14), 1,1-dimethyl-2-hydroxyethylamine, And a conductive ink composition containing copper formate particles.
To 10 g of tetrahydrofuran, 0.9 g of copper particles (copper powder manufactured by Alfa Aesar) (metal particles (A)) having an average particle diameter of 2.49 μm and silver-coated copper particles having an average particle diameter of 0.36 μm (Mitsui Metals Co., Ltd.) 1. Ag (wet copper powder) (metal particles (B)) 0.1 g (metal powder: 90% by weight of particle A, 10% by weight of metal particle B), which is an alkanolamine represented by the general formula (2) 1, Add 0.07 g of 1-dimethyl-2-hydroxyethylamine (coordinating compound) and 0.05 g of copper formate particles (primary average particle diameter 210 nm) obtained in Reference Example 1, and completely disperse in a mortar. It knead | mixed fully until it became. From this slurry-like mixture, tetrahydrofuran and excess water were distilled off at 40 ° C. under reduced pressure to prepare a paste-like conductive ink composition. The viscosity of the obtained conductive ink composition (metal powder: 89.2% by weight, coordination compound: 6.3% by weight, copper formate particles: 4.5% by weight) was 221 Pa · s (hereinafter referred to as “the following”). In order to simplify the notation, this is referred to as “conductive ink D”).

Example 5 Metal powder containing two types of copper particles having different average particle sizes (average particle size ratio metal particles (B) / metal particles (A) = 0.35), 3- (dimethylamino) -1, Preparation of conductive ink composition containing 2-propanediol and copper formate particles.
To 10 g of tetrahydrofuran, 0.95 g of copper particles having an average particle size of 1.02 μm (copper powder manufactured by Alfa Aesar) (metal particles (A)) and copper particles having an average particle size of 0.36 μm (wet made by Mitsui Kinzoku Co., Ltd.) Copper powder) (metal particles (B)) 0.05 g (metal powder: 95% by weight of particle A, 5% by weight of metal particle B), 3- (dimethylamino) which is an alkanolamine represented by the general formula (3) Add 0.6 g of -1,2-propanediol (coordinating compound) and 0.4 g of the copper formate particles (primary average particle diameter 210 nm) obtained in Reference Example 1 and completely disperse in a mortar. Kneaded thoroughly. This slurry-like mixture was distilled under reduced pressure at 40 ° C. to distill off tetrahydrofuran and excess water, thereby obtaining a paste-like conductive ink composition (metal powder: 50.0% by weight, 3- (dimethylamino). ) -1,2-propanediol: 30.0% by weight, copper formate particles: 20.0% by weight). The viscosity of the obtained conductive ink composition was 112 Pa · s (hereinafter, for the sake of brevity, this is referred to as “conductive ink E”).

[Comparative Example 1] Conductive material containing copper particles and metal powder containing silver particles (average particle size ratio metal particle (B) / metal particle (A) = 0.58), n-octylamine, and copper formate particles Of a water-based ink composition.
To 10 g of tetrahydrofuran, 0.9 g of copper particles having an average particle size of 2.49 μm (Copper Powder made by Alfa Aesar) (metal particles (A)) and silver particles having an average particle size of 1.44 μm (Silver made by Alfa Aesar) Powder) (metal particles (B)) 0.1 g (metal powder: 90% by weight of particles A, 10% by weight of metal particles B), 0.23 g of n-octylamine, and copper formate particles obtained in Reference Example 1 (Average particle diameter 210 nm) 0.22 g was added, and kneaded sufficiently in a mortar until it was completely dispersed. The slurry-like mixture was subjected to distillation of tetrahydrofuran and excess water at 40 ° C. under reduced pressure to obtain a paste-like conductive ink composition (metal powder: 69.0% by weight, n-octylamine: 15.8 wt%, copper formate particles: 15.2 wt%). The viscosity of the obtained conductive ink composition was 158 Pa · s (hereinafter, for simplicity of description, this is referred to as “conductive ink F”).

[Comparative Example 2] Metal powder containing two types of copper particles having different average particle sizes (average particle size ratio metal particles (B) / metal particles (A) = 0.086), n-octylamine, and copper formate particles Preparation of a conductive ink composition containing
To 10 g of tetrahydrofuran, 0.9 g of copper particles (wet copper powder manufactured by Mitsui Kinzoku Co., Ltd.) (metal particles (A)) having an average particle diameter of 4.18 μm and copper particles (manufactured by Mitsui Kinzoku Co., Ltd.) are used. Wet copper powder) (metal particles (B)) 0.1 g (metal powder: 90% by weight of particle A, 10% by weight of metal particles B), 0.23 g of n-octylamine, and formic acid obtained in Reference Example 1 0.22 g of copper particles (average particle size 210 nm) was added, and kneaded sufficiently in a mortar until it was completely dispersed. The slurry-like mixture was subjected to distillation of tetrahydrofuran and excess water at 40 ° C. under reduced pressure to obtain a paste-like conductive ink composition (metal powder: 69.0% by weight, n-octylamine: 15.8 wt%, copper formate particles: 15.2 wt%). The viscosity of the obtained conductive ink composition was 148 Pa · s (hereinafter, for the sake of brevity, this is referred to as “conductive ink G”).

[Comparative Example 3] Conductive ink containing copper powder containing two types of copper particles (average particle size ratio metal particles (B) / metal particles (A) = 0.35), n-octylamine, and ethylene glycol Preparation of the composition.
To 10 g of tetrahydrofuran, 0.95 g of copper particles having an average particle size of 1.02 μm (copper powder manufactured by Alfa Aesar) (metal particles (A)) and copper particles having an average particle size of 0.36 μm (wet made by Mitsui Kinzoku Co., Ltd.) (Copper powder) (metal particles (B)) 0.05 g (metal powder: 95% by weight of particle A, 5% by weight of metal particle B), 0.4 g of n-octylamine and 0.4 g of ethylene glycol were added, The mixture was sufficiently kneaded until it was completely dispersed in a mortar. The slurry-like mixture was subjected to distillation of tetrahydrofuran and excess water at 40 ° C. under reduced pressure to obtain a paste-like conductive ink composition (metal powder: 55.6% by weight, n-octylamine: 22.2 wt%, ethylene glycol: 22.2 wt%). The viscosity of the obtained conductive ink composition was 78 Pa · s (hereinafter, for the sake of brevity, this is referred to as “conductive ink H”).

[Examples 6 to 10, Comparative Examples 4 to 6] Conductivity evaluation and film density evaluation.
Conductive inks A to H are applied on a glass substrate by a screen printing method (screen specifications: mesh number: 200, wire diameter: 40 μm, weaving thickness: 115 μm, mesh opening: 87 μm, space ratio: 46.9%, paste transmission Volume: 53.94 mg / cm ³ ) was applied to form a uniform coating film having a width of 2 mm × length of 30 mm and a film thickness of 54 μm.

  Next, in a heating furnace in which nitrogen gas was circulated at a flow rate of 6 L / min, the glass substrate coated with these conductive inks was subjected to heat treatment for 30 minutes to obtain a conductive film (electrically conductive portion). Each heating temperature is shown in Table 1.

  The conductivity was evaluated by comparing the volume resistivity calculated from the measured surface resistivity and film thickness in each conductive film.

  The surface resistivity was measured with a four-probe resistance measuring machine (trade name: Loresta GP, manufactured by Mitsubishi Chemical Corporation).

  Regarding the film thickness, each formed conductive film was cut, the cross section was observed with a scanning electron microscope (SEM), and the average film thickness was taken as the value. That is, for each electrical conduction site, three locations were selected at random from the field of view observed with a scanning electron microscope (SEM) and photographed at a magnification of 5000 times. The film thickness was measured, these values were divided by the photographing magnification, and the value obtained by arithmetically averaging the film thickness at the three locations was taken as the film thickness of each conductive film.

  The film density was evaluated by calculating the film density from the volume and weight of each conductive film formed.

  The results of these evaluations are also shown in Table 1.

  As is clear from Table 1, in Examples 6 to 10, the conductive film produced from the conductive ink composition of the present invention showed good conductivity and high film density.

  On the other hand, in Comparative Examples 4 and 5, the conductive film produced from the conductive ink composition using the metal powder in which the ratio of the average particle diameter of the small particles and the large particles is out of the range of the present invention is conductive. Or the film density deteriorated. In Comparative Example 6, the conductive film produced from the conductive ink composition containing no copper formate particles had good film density but low conductivity.

Claims (14)

A conductive ink composition comprising a metal powder, a coordinating compound, and copper formate particles, wherein the metal powder has an average particle diameter ratio of metal particles (B) / metal particles (A) = 0.10 to 0. A conductive ink composition comprising a metal powder in a range of .45 times.   The metal particles (A) and / or the metal particles (B) are at least one selected from the group consisting of gold particles, silver particles, copper particles, platinum particles, palladium particles, nickel particles, tin particles, and silver-coated copper particles. The conductive ink composition according to claim 1, which is contained.   The average particle diameter of the metal particles (A) is in the range of 0.1 to 10 µm, and the average particle diameter of the metal particles (B) is in the range of 0.01 to 4.5 µm. Or 3. The conductive ink composition according to 2.   The weight concentration of the metal particles (A) is in the range of 70 to 99% by weight and the weight concentration of the metal particles (B) is in the range of 1 to 30% by weight with respect to the total amount of the metal powder. The electroconductive ink composition in any one of 1-3. The coordination compound is composed of an aliphatic amine, an aromatic amine, a heterocyclic amine, an alkoxyamine represented by the following general formula (1), and an alkanolamine represented by the following general formula (2) or (3). The conductive ink composition according to claim 1, which is at least one selected from the group.

[R ₁ and R ₂ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R ₃ represents a straight-chain alkyl group having 1 to 6 carbon atoms, a branched or cyclic alkyl group having 3 to 6 carbon atoms. Represents a group, and X represents a methylene group or an ethylene group. ]

[R ₄ and R ₅ each independently represents a hydrogen atom, a methyl group, or an ethyl group, R ₆ and R ₇ each independently represent a hydrogen atom or a methyl group, and Y represents a methylene group or an ethylene group. Represents. ]

[R ₈ and R ₉ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and Z represents a methylene group or an ethylene group. ]   The coordinating compound is ethylamine, n-propylamine, i-propylamine, n-butylamine, n-pentylamine, n-hexylamine, cyclohexylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n -Decylamine, n-undecylamine, n-dodecylamine, piperidine, pyridine, piperazine, N-methylpiperazine, N-ethylpiperazine, homopiperazine, hexamethyleneimine, 2-methoxyethylamine, N, N-dimethyl-2- Methoxyethylamine, 2-ethoxyethylamine, N, N-dimethyl-2-ethoxyethylamine, 2-n-propoxyethylamine, N, N-dimethyl-2-n-propoxyethylamine, 2-n-butoxyethylamine, N, N- Dimethyl-2-n Butoxyethylamine, 3-methoxypropylamine, N, N-dimethyl-3-methoxypropylamine, 3-ethoxypropylamine, N, N-dimethyl-3-ethoxypropylamine, 3-n-propoxypropylamine, N, N -Dimethyl-3-n-propoxypropylamine, 3-n-butoxypropylamine, N, N-dimethyl-3-n-butoxypropylamine, ethanolamine, N-methylethanolamine, N, N-dimethylethanolamine, N-ethylethanolamine, N, N-diethylethanolamine, 1,1-dimethyl-2-hydroxyethylamine, N, N-dimethyl-1,1-dimethyl-2-hydroxyethylamine, 3-hydroxypropylamine, N, N-dimethyl-3-hydroxypropylamino 3-amino-1,2-propanediol, 3- (dimethylamino) -1,2-propanediol, 3- (diethylamino) -1,2-propanediol, 4-amino-1,2-butanediol, And at least one selected from the group consisting of 4- (dimethylamino) -1,2-butanediol. 6. The conductive ink composition according to claim 1.   7. The conductive ink composition according to claim 1, wherein the average particle diameter of the copper formate particles is in the range of 0.01 to 5 μm.   The concentration of the metal powder is 1 to 98% by weight, the concentration of the coordinating compound is 1 to 80% by weight, and the concentration of the copper formate particles is 1 to 80% by weight with respect to the total amount of the conductive ink composition. The electroconductive ink composition according to claim 1, wherein the electroconductive ink composition is provided.   The conductive ink composition according to claim 1, further comprising a diluent.   The conductive ink composition according to claim 1, wherein the viscosity of the conductive ink composition is in the range of 1 to 1000 Pa · s.   An electrically conducting part produced by applying or filling the conductive ink composition according to any one of claims 1 to 10 onto a base material and subjecting the base material to heat treatment.   The substrate is one or two or more composite substrates selected from the group consisting of resin, paper, glass, silicon-based semiconductor, compound semiconductor, metal oxide, metal nitride, and wood The electrical conduction site according to claim 11.   The electrically conducting portion according to claim 11 or 12, wherein the temperature of the heat treatment is in a range of 60 to 300 ° C.   The electrically conductive portion according to claim 11, wherein heat treatment is performed in a non-oxidizing atmosphere.