JP5983805B2 - Conductive ink composition, method for producing electrically conductive portion, and use thereof - Google Patents

Description

  The present invention relates to a conductive ink composition, a method for producing an electrically conductive portion, and use thereof. The conductive ink composition of the present invention can be suitably used as a circuit pattern forming material for a wiring board in the electronics field.

  2. Description of the Related Art In recent years, a technique for forming a desired pattern by using an ink-jet printing method or a screen printing method using a dispersion of metal fine particles as a conductive ink and forming an electrically conductive portion such as a wiring on a circuit board has attracted attention. . When the average particle size of metal fine particles is about several nanometers to several tens of nanometers, the melting point of the metal particles is significantly lower than that of bulk metal, and the particles are fused at a low temperature. To obtain an electrically conductive portion. At present, such a composition for forming a conductive pattern is mainly one containing silver fine particles.

  However, silver has a problem that electromigration tends to occur, and silver itself is an expensive metal. 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.

  Therefore, there is a demand for a material for forming an electrically conductive portion that can reduce the cost, is less likely to cause electromigration, and can form wiring having copper as a main component with high conductivity by a printing method.

  As a material for forming an electrical conduction site of copper, an organic compound having a heteroatom such as nitrogen, oxygen, sulfur, etc. in the molecular structure is adsorbed on the surface of the metal copper, preventing contact with oxygen or water and preventing oxidation. Many methods have been proposed that use copper fine particles having an average particle diameter of several nanometers to several hundreds of nanometers, which suppresses aggregation between metal copper fine particles. For example, a method using alkylamine as an oxidation inhibitor has been proposed (see, for example, Patent Document 1).

  However, the material for forming an electrical conduction site using such metal copper fine particles removes the oxidation inhibitor that covers the surface of the metal copper fine particles in the step of making the electrical conduction site after applying the metal copper fine particles, Generally, in order to fuse metal copper fine particles, heating at a high temperature of about 300 ° C. is necessary, and there is a problem that the applicable base materials are limited. Moreover, since there are many cases where heating in a reducing atmosphere containing hydrogen is required in order to suppress oxidation of metallic copper, there has been a serious problem in terms of safety.

  Therefore, a material for forming an electrically conductive part that can form an electrically conductive part of copper by heating at a relatively low temperature in a non-reducing atmosphere that does not contain copper fine particles and does not contain hydrogen has been studied. .

  For example, there is a method of depositing a copper layer on a substrate by bringing a mixed product composed of copper (II) formate and an alkoxyalkylamine into contact with the substrate at 80 to 200 ° C. and 0.1 to 5 bar. It has been proposed (see, for example, Patent Document 2). In addition, by using a metal salt mixture for forming a metal pattern that contains at least a metal salt and a reducing agent and has a viscosity of 3 to 50 mPa · s at 25 ° C., a pattern is drawn on the substrate, and then heated. A method of forming a metal film has been proposed (see, for example, Patent Document 3). According to these methods, a copper film or a metal film is formed by heating at a temperature of about 180 ° C. in a non-reducing atmosphere.

  However, since the method of Patent Document 2 is a solution in which copper (II) formate is completely dissolved in an alkoxyalkylamine, pattern formation by a screen printing method having a low viscosity and an adaptive viscosity of 10 to 300 Pa · s is possible. There are problems such as difficulty and changes in viscosity and surface tension during the heat treatment after application to the substrate, and there are problems such as large changes in wiring width and shape after application and after heating. There was a risk of not being able to.

  Also in the method of Patent Document 3, since the viscosity of the metal salt mixture is as low as 3 to 50 mPa · s, there is a problem that it is difficult to form a pattern by the screen printing method as described above, and the metal salt concentration is a metal salt mixture. If the metal content is 10% by weight or less with respect to the total weight and the metal content is low, it is necessary to repeat the coating many times in order to obtain the desired film thickness when forming the electrically conductive portion. There was a problem that it could not be used industrially.

  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, in the formation of an electrically conductive portion mainly composed of copper, the conductive ink composition can form an electrically conductive portion at a temperature at which a resin can be used as a base material, and can form a pattern by a screen printing method. Development of things was desired.

JP 2007-32215 A Japanese Patent Laying-Open No. 2005-2471 JP 2008-205430 A

  The present invention has been made in view of the above-described background art, and its purpose is to form an electrically conductive part at a temperature at which a resin can be used as a base material in the formation of an electrically conductive part mainly composed of copper. It is possible to provide a conductive ink composition capable of forming a pattern by a screen printing method, a method for producing an electrically conductive portion using the same, and a use thereof.

  As a result of intensive studies to solve the above problems, the present inventors have obtained fine particles (A) of a copper salt comprising a carboxylic acid having a reducing power and copper ions, and a coordinating compound (B). A conductive ink composition was found. The conductive ink composition is found to be capable of forming an electrically conductive portion at a temperature at which a resin can be used as a base material, and to form a pattern by a screen printing method, thereby completing the present invention. It came.

That is, the present invention is a conductive ink composition, a method for producing an electrically conductive portion, and uses thereof as described below.
[1] One or two or more kinds of arrangements selected from the group consisting of copper salt fine particles (A) comprising a reducing carboxylic acid and copper ions, alkanethiols, aliphatic amines, aromatic amines, and cyclic amines A conductive ink composition containing a potential compound (B) and a dispersion medium (D) and having a viscosity in the range of 10 to 300 Pa · s.
[2] A copper salt composed of a carboxylic acid having a reducing power and copper ions is composed of copper formate, copper hydroxyacetate, copper glyoxylate, copper lactate, copper oxalate, copper tartrate, copper malate, and copper citrate. The conductive ink composition as described in [1] above, which is one or more selected from the group.
[3] The conductive ink composition as described in [1] or [2] above, wherein the primary average particle diameter of the copper salt fine particles (A) is in the range of 1 nm to 5 μm.
[4] The conductive ink composition as described in any one of [1] to [3], wherein the metal catalyst contains fine metal particles and / or a metal compound.
[5] The conductive ink according to [4], wherein the metal fine particles are one or more selected from the group consisting of gold fine particles, silver fine particles, copper fine particles, platinum fine particles, and palladium fine particles. Composition.
[6] The conductive ink composition as described in [4] or [5] above, wherein the average particle size of the metal fine particles is in the range of 1 to 1000 nm.
[7] The conductivity according to [4], wherein the metal compound is a compound composed of one or more metal elements selected from the group consisting of gold, silver, copper, platinum, and palladium. Ink composition.
[8] The conductive ink according to [4] or [7], wherein the metal compound is one or more selected from the group consisting of metal salts, metal oxides, and metal sulfides. Composition.
[9] The conductive ink composition according to any one of [1] to [8] is applied or filled in a desired portion of the base material where electrical continuity is desired to be obtained, and the base material is heat-treated. A method for producing an electrically conducting portion.
[10] 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 method for producing an electrically conductive portion according to [9] above, which is characterized in that
[11] The method for producing an electrically conductive part according to [9] or [10] above, wherein the temperature of the heat treatment is in a range of 60 ° C to 300 ° C.
[12] The method for producing an electrically conductive portion according to any one of [9] to [11], wherein the heat treatment is performed in a non-oxidizing atmosphere.
[13] An electrically conductive portion formed by the manufacturing method according to any one of [9] to [12].
[14] An image display device comprising an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[15] A light-emitting device having an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[16] A circuit board characterized by having an electrically conductive portion partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[17] A capacitor having an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[18] A solar cell characterized by having an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[19] A secondary battery comprising an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[20] A radio wave system recognition tag having an electrically conductive part that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].
[21] An electromagnetic shielding shield characterized by having an electrically conductive portion that is partially or wholly manufactured by the manufacturing method according to any one of [9] to [12].

  The present invention has the following effects.

  (1) Since the conductive ink composition of the present invention can form an electrically conductive portion such as a conductive pattern by a simple method such as coating, filling, and heating, energy saving, low cost, and low environment. The load can be achieved and is extremely useful industrially.

  Further, the conductive ink composition of the present invention contains fine particles (A) of a copper salt composed of a carboxylic acid having a reducing power and copper ions, and since copper is a main metal component, it is excellent in copper. It is possible to form an electrically conducting portion having characteristics.

  Further, since the conductive ink composition of the present invention contains, as a solid, fine particles (A) of a copper salt composed of a carboxylic acid having a reducing power and copper ions, and a metal catalyst (C) as necessary, The metal concentration is high, the number of coatings for increasing the film thickness can be reduced, and the work efficiency is excellent. 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 dispersion medium (D) as necessary, a pattern can be formed by a screen printing method.

  (2) The method for producing an 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, such as nitrogen. Electrically conductive sites can be formed by heating in an inert atmosphere, and the safety is excellent.

  Moreover, according to the manufacturing method of the electrical conduction site | part of this invention, formation of an electrical conduction site | part is possible at the temperature which can utilize resin as a base material, and it is excellent in versatility.

  The present invention is described in further detail below.

  First, the conductive ink composition of the present invention will be described.

  The conductive ink composition of the present invention has a copper salt fine particle (A) composed of a carboxylic acid having a reducing power and copper ions (hereinafter referred to as “copper salt fine particle (A)” for the sake of brevity). Called. ], A coordination compound (B) is included.

  By conducting the heat treatment of the conductive ink composition of the present invention, the copper ion contained in the copper salt fine particles (A) is reduced by a carboxylic acid having a reducing power to become a copper metal, thereby forming an electrically conductive site. It plays a role in developing the electrical conductivity of. The coordinating compound (B) plays a role of improving the dispersibility of the copper salt fine particles (A) and stabilizing the reduction reaction of the copper ions at the time of forming the electrically conductive site.

  In the conductive ink composition of the present invention, the copper salt comprising a carboxylic acid having a reducing power and a copper ion is a copper salt having a copper ion as a cation species and a carboxylic acid having a reducing power as an anion species. Well, not particularly limited. Examples thereof include one or more selected from the group consisting of monovalent copper ions, divalent copper ions, and trivalent copper ions, and a copper salt composed of a carboxylic acid having a reducing power. Among these, a copper salt composed of a divalent copper ion and a carboxylic acid having a reducing power is preferable from the viewpoint of stability and availability.

  For example, copper salts composed of copper ions and carboxylic acids having reducing power include copper formate, hydroxyacetate copper, glyoxylate copper, lactate, copper oxalate, tartrate, malate, and citric acid. One kind or two or more kinds selected from the group consisting of acid copper can be mentioned, and among these, copper formate and / or copper oxalate is preferable from the viewpoint of cost.

  In the conductive ink composition of the present invention, a copper salt composed of a copper ion other than these and a carboxylic acid having a reducing power may be used, but it is difficult to obtain or expensive. There may be industrial disadvantages. Moreover, as a copper salt which consists of a carboxylic acid which has a copper ion and a reducing power, it may be a commercially available one or one synthesized by a known method, and furthermore, a compound containing a copper ion and a carboxylic acid having a reducing power are mixed. By doing so, even those formed in the system can be used without any limitation, and are not particularly limited.

  In the conductive ink composition of the present invention, the purity of the copper salt composed of carboxylic acid having copper ions and reducing power is not particularly limited, but when the conductive thin film is too low purity, Since there exists a possibility of having a bad influence on electroconductivity, 95% or more is preferable and 99% or more is further more preferable.

  In the conductive ink composition of the present invention, the copper salt fine particles (A) are not particularly limited, and examples thereof include copper formate fine particles, hydroxy hydroxy copper fine particles, copper glyoxylate fine particles, copper lactate fine particles, and oxalic acid. One type or two or more types selected from the group consisting of copper fine particles, copper tartrate fine particles, copper malate fine particles, and copper citrate fine particles may be mentioned. Of these, copper formate fine particles and / or copper oxalate fine particles are preferable from the viewpoint of cost and availability.

In the conductive ink composition of the present invention, the primary average particle size of the copper salt fine particles (A) is not particularly limited, but is preferably in the range of 1 nm or more and less than 5 μm. When the particle diameter is less than 1 nm, the activity of the particle surface becomes very high and may be dissolved. When dissolved, it is not preferable because, when reprecipitated, other fine particles may be precipitated as nuclei and cause coarsening of the fine particles. In addition, when the thickness is 5 μm or more, it is difficult to adapt to a conductive ink composition that can form a pattern such as a wiring by a printing method, or when forming an electrically conductive portion, the inside of the particle does not react completely, and the metal Reduction to copper becomes insufficient, which may adversely affect the conductivity of the formed electrical conduction site. Therefore, it is desirable to be within the above range.

  In the conductive ink composition of the present invention, the copper salt fine particles (A) may be commercially available or synthesized by a known method, or a compound containing copper ions and a carboxylic acid having a reducing power. Even if it mixes and what was formed in the system can be used without any limitation, it does not specifically limit.

  The method for producing the copper salt fine particles (A) is not particularly limited, for example, a method of pulverizing a copper salt powder composed of a carboxylic acid having a reducing power and copper ions by mechanical pulverization, Examples thereof include a method of precipitating fine particles of a copper salt comprising a copper ion and a carboxylic acid having a reducing power from a copper salt solution comprising the carboxylic acid having a copper ion and a reducing power. Among these, since the reproducibility of the particle size is good and a large amount of solvent and large-scale equipment are not required, a copper salt powder composed of a carboxylic acid having a reducing power and copper ions is mechanically pulverized. A method of pulverizing is preferred.

  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 particle diameter of the copper salt fine particles (A), a general particle 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 photo, select the 100 most likely particles, measure the diameter with a ruler, calculate the particle size by dividing the measurement magnification, and obtain these values by arithmetically averaging them. Can do.

  In the conductive ink composition of the present invention, the coordination compound (B) is one or more selected from the group consisting of alkanethiols, aliphatic amines, aromatic amines, and cyclic amines.

  For example, as alkanethiols, specifically, ethanethiol, n-propanethiol, i-propanethiol, n-butanethiol, i-butanethiol, t-butanethiol, n-pentanethiol, n-hexanethiol , Cyclohexanethiol, n-heptanethiol, n-octanethiol, 2-ethylhexanethiol and the like.

  Specific examples of the aliphatic amine include ethylamine, n-propylamine, i-propylamine, n-butylamine, i-butylamine, t-butylamine, n-pentylamine, n-hexylamine, cyclohexylamine, n-heptylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecyl Amine, n-hexadecylamine, benzylamine, N-methylethylamine, N-methyl-n-propylamine, N-methyl-i-propylamine, N-methyl-n-butylamine, N-methyl-i-butylamine, N-methyl-t-butylamine, N-methyl-n-pentyl Min, N-methyl-n-hexylamine, N-methylcyclohexylamine, N-methyl-n-heptylamine, N-methyl-n-octylamine, N-methyl-2-ethylhexylamine, N-methyl-n- Nonylamine, N-methyl-n-decylamine, N-methyl-n-undecylamine, N-methyl-n-dodecylamine, N-methyl-n-tridecylamine, N-methyl-n-tetradecylamine, N -Methyl-n-pentadecylamine, N-methyl-n-hexadecylamine, N-methyl-benzylamine and the like are exemplified.

  Specific examples of the aromatic amine include aniline, p-toluidine, 4-ethylaniline, N-methylaniline, N-methyl-p-toluidine, N-methyl-4-ethylaniline and the like. .

  Specific examples of the cyclic amine include pyrrolidine, pyrrole, piperidine, pyridine, hexamethyleneimine, imidazole, pyrazole, piperazine, N-methylpiperazine, N-ethylpiperazine, and homopiperazine.

  In the conductive ink composition of the present invention, the coordination compound (B) may be a commercially available product or may be synthesized by a known method.

  In the conductive ink composition of the present invention, the purity of the coordination compound (B) is not particularly limited, but is preferably 95% or more, more preferably 99% or more in consideration of use in the field of electronic materials. preferable.

  The conductive ink composition of the present invention preferably contains a metal catalyst (C) for the following reasons.

  That is, the conductive ink composition of the present invention can be used as a conductive ink without containing the metal catalyst (C), but by containing the metal catalyst (C), for example, the conductive ink composition can be used. When the heat-sensitive ink composition is applied onto a substrate and heat-treated, it plays a role in promoting reduction of copper ions contained in the fine particles (A) of the copper salt, and as a result, the processing temperature is lowered, Processing time can be shortened.

  The metal fine particles used in the metal catalyst (C) are not particularly limited. For example, one or two selected from the group consisting of gold, silver, copper, platinum, palladium, rhodium, iridium, ruthenium, and osmium. The thing containing the metal seed | species more than a seed | species is mentioned. These metal species may be simple substances or alloys with other metals. Among these, one or two or more selected from the group consisting of gold fine particles, silver fine particles, copper fine particles, platinum fine particles, and palladium fine particles are selected from the viewpoint of cost, availability, and catalytic ability at the time of forming an electrically conductive site. preferable.

  Although metal fine particles other than these may be used for the metal catalyst (C), the metal fine particles may be oxidized by the copper ions contained in the copper salt fine particles (A), or the catalytic ability may be reduced or expressed. Otherwise, the reduction precipitation rate from the copper salt fine particles (A) to the metal copper may be reduced, and therefore, it is desirable to use the metal fine particles described above.

  The metal fine particles used for the metal catalyst (C) preferably have an average particle diameter in the range of 1 to 1000 nm. When the particle diameter of the metal fine particles is less than 1 nm, the activity of the metal surface becomes very high, and there is a risk of being oxidized or dissolved. On the other hand, when the thickness exceeds 1000 nm, the metal fine particles may settle when stored for a long time. Therefore, it is desirable to be within the above range.

  In the present invention, as a method for measuring the particle diameter of the metal fine particles, a general particle 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 photo, select the 100 most likely particles, measure the diameter with a ruler, calculate the particle size by dividing the measurement magnification, and obtain these values by arithmetically averaging them. Can do.

  The metal fine particles used for the metal catalyst (C) may be commercially available or may be synthesized by a known method, and is not particularly limited. As a known synthesis method, for example, a gas phase method (dry method) in which a synthesis reaction is performed by a physical method such as a sputtering method or a vapor deposition method in gas, or a base metal compound solution is reduced in the presence of a surface protective agent. A liquid phase method (wet method) or the like for precipitating fine metal particles is generally known. Among these, as an example of a generally used liquid phase method, metal fine particles are obtained by heating a metal complex ion dissolved in a mixed solvent of water containing polyvinyl alcohol as a protective agent and methanol or ethanol. (E.g., "Journal of Macromolecular Science: Part A. Pure & Applied Chemistry", 1979, Vol. 13, p. 727), and the vicinity of their boiling points using polyols such as ethylene glycol and diethylene glycol Alternatively, a method of slowly reducing and precipitating metal ions to obtain metal fine particles by heating at a temperature lower than that (see, for example, “MRS Bulletin”, 1989, Vol. 14, p. 29) can be used.

  The purity of the metal fine particles used in the metal catalyst (C) is not particularly limited, but if it is too low in purity, there is a possibility of adversely affecting the conductivity when the conductive thin film is used. The above is preferable, and 99% or more is more preferable.

  On the other hand, the metal compound used for the metal catalyst (C) is not particularly limited, but for example, one or more selected from the group consisting of gold, silver, copper, platinum, palladium, rhodium, iridium, ruthenium, and osmium. A compound containing two or more metal species is preferred. Among these, from the viewpoint of cost and availability, it is preferably a compound containing one or more metal species selected from the group consisting of gold, silver, copper, platinum, and palladium, silver, and More preferably, it contains palladium. The metal compound is not particularly limited as long as it is a compound containing the above metal ions, and examples thereof include metal salts, metal oxides, and metal sulfides. Among these, it is preferable to use a metal salt from the viewpoint of solubility.

  Although it does not specifically limit as a metal salt, What consists of a metal ion and inorganic anion species and / or organic anion species is preferable. Examples include metal halides, metal nitrates, metal nitrites, metal carbonates, metal carboxylates, metal tetrafluoroborate, complex salts of metals and acetylacetone derivatives, among these, cost and solubility aspects Therefore, metal carboxylates and / or complex salts of metals and acetylacetone derivatives are preferred.

  Specifically, as the metal carboxylate, for example, silver formate, silver acetate, silver trifluoroacetate, silver propionate, silver butyrate, silver isobutyrate, silver valerate, silver isovalerate, silver pivalate, hexane Silver, silver heptanoate, silver cyclohexanecarboxylate, silver octanoate, silver 2-ethylhexanoate, silver nonanoate, silver decanoate, silver undecanoate, silver dodecanoate, silver tridecanoate, silver oleate, silver linoleate Silver linolenate, silver benzoate, palladium formate, palladium acetate, palladium trifluoroacetate, palladium propionate, palladium butyrate, palladium isobutyrate, palladium valerate, palladium isovalerate, palladium pivalate, palladium hexanoate, heptanoic acid Palladium, palladium cyclohexanecarboxylate, palladium octoate, 2-ethyl Hexane silver palladium, nonanoic acid, palladium decanoic acid, palladium undecanoic acid, palladium dodecanoic acid, tridecanoic acid, palladium oleic acid, palladium linoleic acid, palladium linolenic acid, benzoic acid palladium and the like as preferred.

  Moreover, as a complex salt of a metal and an acetylacetone derivative, for example, acetylacetonate silver, hexafluoroacetylacetonate silver, acetylacetonatopalladium, hexafluoroacetylacetonatopalladium and the like are preferable.

  Among these, from the viewpoint of cost and solubility, metal carboxylates such as silver acetate, silver propionate, silver butyrate, silver isobutyrate, palladium acetate, palladium trifluoroacetate, palladium propionate, palladium butyrate, palladium isobutyrate, etc. Is preferred.

  Although metal compounds other than these may be used for the metal catalyst (C), they may be industrially disadvantageous because they are difficult to obtain or expensive. Moreover, as a metal compound, what was synthesize | combined by the commercially available thing and the well-known method may be sufficient, and also in a system by mixing the compound and inorganic anion species, and / or organic anion species containing a metal ion, etc. The formed one can be used without any limitation, and is not particularly limited. Further, it may be reduced in the system due to the influence of the reducing component to form a zero-valent complex or metal particles.

  In the conductive ink composition of the present invention, the purity of the metal compound is not particularly limited, but when it has a low purity, there is a possibility of adversely affecting the conductivity when an electrically conductive portion is formed. 95% or more is preferable, and 99% or more is more preferable.

  In the conductive ink composition of the present invention, the concentration of each component is not particularly limited, but 0.1 to 80% by weight of the copper salt fine particles (A) and the coordinating compound with respect to the total amount of the conductive ink composition. It is preferable to contain (B) in the range of 0.1 to 80% by weight and metal catalyst (C) in the range of 0 to 50% by weight [however, fine particles of copper salt (A), coordination property The total amount of the compound (B) and the metal catalyst (C) does not exceed 100% by weight. ].

  If the concentration of the copper salt fine particles (A) is less than 0.1% by weight, the amount of metallic copper generated from the copper salt fine particles (A) is small, and there may be a case where an electrically conductive portion having a sufficient film thickness cannot be formed. If it exceeds 80% by weight, the viscosity or solidification of the conductive ink composition may occur and the workability may decrease.

  Further, if the concentration of the coordinating compound (B) is less than 0.1% by weight, the fine particles of the copper salt composed of carboxylic acid having a copper ion and a reducing power may not be sufficiently dispersed, exceeding 80% by weight. Application of conductive ink composition for obtaining an electrically conductive portion having a desired film thickness is reduced in copper concentration in the total amount of the conductive ink composition. The amount increases, which is industrially disadvantageous.

  Further, the concentration of the metal catalyst (C) is preferably 1 wt. Ppb or more in order to express its catalytic ability, but even if it is used in excess of 50 wt. In addition to this, the content of metallic copper per unit weight of the conductive ink composition is lowered, which may be industrially disadvantageous.

  In the conductive ink composition of the present invention, the copper salt fine particles (A) and the metal catalyst (C) are not complexed to form these composite fine particles. Here, examples of the compounding method include a physical compounding method and a chemical compounding method. Specifically, the physical complexing method includes a method of supporting a catalytic metal on a copper salt composed of a carboxylic acid having a reducing power and a copper ion, and a copper salt comprising a carboxylic acid having a reducing power and a copper ion. Examples thereof include a method of adsorbing a catalytic metal, a method of depositing a catalytic metal on a copper salt comprising a carboxylic acid having a reducing power and copper ions, and the like. Further, as a chemical compounding method, specifically, a method of compounding a copper salt composed of a carboxylic acid having a reducing power and a copper ion and a catalytic metal, or a copper compound comprising a carboxylic acid having a reducing power and a copper ion. Examples thereof include a method of alloying a part of the salt with the catalyst metal.

  The conductive ink composition of the present invention may contain the dispersion medium (D) in addition to the above components.

  In the conductive ink composition of the present invention, the dispersion medium (D) 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 dispersion medium (D) is not particularly limited as long as it does not react with the copper salt fine particles (A), and examples thereof include alcohols, ethers and esters. , One or more selected from the group consisting of aliphatic hydrocarbons and aromatic hydrocarbons.

  For example, specific examples of alcohols include hexanol, heptanol, octanol, cyclohexanol, benzyl alcohol, terpineol, and the like.

  Specific 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, tetrahydro Examples include pyran and 1,4-dioxane.

  Specific 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.

  Specific 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. Illustrated.

  Specific 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 may be one or more selected from the group consisting of hexanol, terpineol, 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 dispersion medium (D) may be commercially available or may be synthesized by a known method.

  In the conductive ink composition of the present invention, the purity of the dispersion medium (D) is not particularly limited, but is preferably 95% or more and more preferably 99% or more in consideration of use in the field of electronic materials.

  In the conductive ink composition of the present invention, the concentration of the dispersion medium (D) is not particularly limited. For example, the concentration of the dispersion medium (D) is 0 to 90% by weight with respect to the total amount of the conductive ink composition. [However, the total amount of the copper salt fine particles (A), the coordinating compound (B), the metal catalyst (C) and the dispersion medium (D) does not exceed 100% by weight). ].

  Even if the concentration of the dispersion medium (D) exceeds 90% by weight, not only the improvement effect is not added, but also the concentration of copper in the total amount of the conductive ink composition is reduced, and the electric film having a desired film thickness is obtained. The application amount of the conductive ink composition for obtaining a mechanical conduction site increases, which is industrially disadvantageous.

  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 forming, it is preferable to adjust to the range of 10-300 Pa.s normally.

  In addition to the above components, the conductive ink composition of the present invention may contain an additive (E) such as an electrical conduction site smoothing agent and a surface tension adjusting agent.

  In the conductive ink composition of the present invention, the electrical conduction site smoothing agent is not particularly limited. For example, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, Ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetraethylene glycol monomethyl ether, pentaethylene glycol monomethyl ether, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene Glico Dimethyl ether, can be mentioned oxygen-containing compounds such as pentaethylene glycol dimethyl ether, it is preferable to use one or two or more selected from these.

  In the conductive ink composition of the present invention, the surface tension adjusting agent is not particularly limited, and examples thereof include an organic solvent that does not react with each component of the conductive ink composition, resulting in a desired surface tension. It may be added as appropriate. Examples of such an organic solvent include one selected from the group consisting of alcohols, glycols, ethers, esters, hydrocarbons, and aromatic hydrocarbons, or a mixture of two or more compatible types. Can be mentioned.

  Specifically, as alcohols, methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, sec-butyl alcohol, pentanol, hexanol, heptanol, octanol, cyclohexanol , Benzyl alcohol, terpineol, etc., and glycols include ethylene glycol, propylene glycol, butylene glycol, pentanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, etc., and ethers include Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol Examples thereof include diethyl ether, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, and the esters include methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate, ethyl propionate, propion Examples of hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-undecane, n-dodecane, and cyclohexane. Decalin and the like, and examples of the aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, n-propylbenzene, i-propylbenzene, n-butylbenzene, mesitylene, chlorobenzene, dichlorobenzene and the like.

  The concentration of the additive described above in the conductive ink composition of the present invention is not particularly limited, but the concentration of the additive is preferably in the range of 0 to 50% by weight with respect to the total amount of the conductive ink composition. More preferably, the content is in the range of 0 to 20% by weight [provided that the copper salt fine particles (A), the coordination compound (B), the metal catalyst (C), the dispersion medium (D), and the additive (E) The total amount does not exceed 100% by weight. ].

  Even if the concentration of the additive (E) exceeds 50% by weight, not only the improvement effect is not obtained, but also the content of metallic copper per unit weight of the conductive ink composition is reduced. However, it may be industrially disadvantageous.

  Next, a method for producing an electrically conductive portion using the conductive ink composition of the present invention [hereinafter, for the sake of brevity, this is referred to as “the production method of the present invention”. ] Will be described.

  In the present invention, the “electrical conduction part” means a part having electrical conduction formed by the method for producing an electrical conduction part 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 production method of the present invention is carried out by applying or filling the conductive ink composition of the present invention to a site where it is desired to obtain electrical continuity in the substrate, and subjecting the substrate to heat treatment. For example, after applying the conductive ink composition of the present invention on a substrate, the copper ion contained in the fine particles (A) of the copper salt is reduced by heat treatment, and the coordination compound (B). Is volatilized and removed, and an electrically conductive portion can be easily formed on the substrate.

The specific production method is not particularly limited, but for example,
(A) A method of forming a conductive thin film by applying the conductive ink composition of the present invention on a substrate and heat-treating it in a non-oxidizing atmosphere,
(B) A method in which the conductive ink composition of the present invention is applied onto a substrate in a pattern and heat-treated in a non-oxidizing atmosphere to form wiring and / or electrodes,
(C) The conductive ink composition of the present invention is filled in a through hole provided in a base material, and is heat-treated in a non-oxidizing atmosphere, so that electrical properties between both sides and / or multilayers through the through hole are obtained. A method of forming a conduction site;
(D) After applying the conductive ink composition of the present invention on a base material, the base material and the article to be joined are brought into close contact with each other, and heat-treated in a non-oxidizing atmosphere, thereby the base material and the article to be joined A method of forming an electrically conductive portion by bonding
Etc.

  Moreover, even if the electrically conductive portion is formed by a method other than that described above, there is no problem. For example, steps such as surface treatment, washing, heating, cooling, baking, purification, filtration, classification, drying, and other treatment with a chemical solution can be appropriately performed.

  In the production method of the present invention, a known substrate can be used as the substrate, and is not particularly limited. For example, resin, paper, glass, silicon-based semiconductor, compound semiconductor, metal oxide, metal nitriding 1 type, 2 types or more, or 2 types or more composite base materials which consist of a thing, wood, etc. are mentioned.

  Specifically, low density polyethylene resin, high density polyethylene resin, ABS resin (acrylonitrile-butadiene-styrene copolymer synthetic resin), acrylic resin, styrene resin, vinyl chloride resin, polyester resin (polyethylene terephthalate), polyacetal resin, polysulfone Resin, polyetherimide resin, polyetherketone resin, cellulose derivatives and other resin base materials; uncoated printing paper, finely coated printing paper, coated printing paper (art paper, coated paper), special printing paper, copy paper (PPC paper), unbleached wrapping paper (both kraft paper for heavy bags, both kraft paper), bleached wrapping paper (bleached kraft paper, pure white roll paper), coated paper, chip ball, corrugated cardboard and other paper base materials; Glass substrates such as soda glass, borosilicate glass, silica glass, and quartz glass; Amorph Silicon-based semiconductors such as silicon and polysilicon; compound semiconductors such as CdS, CdTe, and GaAs; metal substrates such as copper plates, iron plates, and aluminum plates; alumina, sapphire, zirconia, titania, yttrium oxide, indium oxide, ITO (indium) Tin oxide), IZO (indium zinc oxide), Nesa (tin oxide), ATO (antimony-doped tin oxide), fluorine-doped tin oxide, zinc oxide, AZO (aluminum-doped zinc oxide), gallium-doped zinc oxide, aluminum nitride Substrate, other inorganic base materials such as silicon carbide; paper-phenol resin, paper-epoxy resin, paper-resin composite such as paper-polyester resin, glass cloth-epoxy resin, glass cloth-polyimide resin, glass cloth-fluorine Examples thereof include composite base materials such as glass-resin composites such as resins.

  In the production method 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. In addition, 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 usually 5000 ppm or less, and 500 ppm or less is further added. preferable.

  In the production method of the present invention, the temperature of the heat treatment is not particularly limited as long as it is a temperature at which the copper ions in the fine particles (A) of the conductive salt are reduced and the coordination compound (B) is volatilized and removed. Although it is not a thing, it is the range of 60-300 degreeC normally, and the range of 80-200 degreeC is still more preferable. If the temperature of the heat treatment is less than 60 ° C., the reduction of the copper ions in the copper salt fine particles (A) may not proceed completely, or the remaining coordinating compound (B) may become prominent. is there. On the other hand, when it exceeds 300 ° C., the organic base material may not be used.

  The heat treatment time may be appropriately selected depending on the temperature and desired conductivity, but is usually about 10 to 60 minutes when a heating temperature of about 200 ° C. is set.

  In the production method of the present invention, the method for applying the conductive ink composition of the present invention to a substrate can be carried out by a known method, and is not particularly limited. For example, screen printing, dip coating, etc. 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 portion, but the film thickness of the conductive ink composition after drying is usually 0. The coating may be performed in the range of 0.01 to 5000 μm, preferably in the range of 0.1 to 1000 μm.

  In the production method of the present invention, the method of filling the through hole provided in the substrate with the conductive ink composition of the present invention can be performed by a known method, and is not particularly limited. Examples thereof include a printing method, an ink jet method, a method of injecting with a dispenser, and the like.

  The production method of the present invention can be used as a part of a process for producing various industrial products, and an industrial product having an electrically conductive portion partially or wholly produced by the production method of the present invention can be obtained. it can.

  The industrial product having an electrically conductive portion partially or wholly manufactured by the manufacturing method of the present invention is not particularly limited. For example, an image display device such as an organic electroluminescence panel, a plasma display panel, a liquid crystal panel, etc. Light emitting devices such as LED (Light Emitting Diode) light emitting devices and organic electroluminescence light emitting devices; 1 layer (single side) printed wiring boards, 2 layer (double sided) printed wiring boards, multilayer printed wiring boards, flexible printed wiring boards, etc. Circuit boards; 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 secondary batteries; Radio wave recognition tags An electromagnetic shielding shield or the like.

  For example, the organic electroluminescence panel is not particularly limited. Specifically, the organic electroluminescence panel having a cathode electrode and / or a cathode electrode extraction portion, which is partially or wholly manufactured by the manufacturing method of the present invention. Luminescence panel; organic electroluminescence panel having an extraction part connected to the through hole and / or an electrically conducting portion through the through hole, partially or wholly manufactured by the manufacturing method of the present invention.

  Further, the plasma display panel is not particularly limited, but specifically, a plasma display panel having bus electrodes and / or address electrodes, which is partially or wholly manufactured by the manufacturing method of the present invention, is exemplified. Is done.

  Further, the liquid crystal panel is not particularly limited, but specifically, a liquid crystal panel having a counter electrode and / or a terminal electrode connected to the counter electrode, partially or wholly manufactured by the manufacturing method of the present invention. Etc. are exemplified.

  Further, the LED light emitting device is not particularly limited. Specifically, the LED light emitting device is connected to an electrically conductive portion or a through hole through a through hole, which is partially or wholly manufactured by the manufacturing method of the present invention. Examples of the LED light emitting device and the like include one or two or more selected from the group consisting of an electrode and an electrically conductive portion where a substrate and a light emitting diode element are joined.

  Further, the organic electroluminescence light emitting device is not particularly limited. Specifically, the organic electroluminescence light emitting device, which is partially or wholly manufactured by the manufacturing method of the present invention, has a cathode electrode and / or an extraction portion of the cathode electrode. An electroluminescence light emitting device; an organic electroluminescence light emitting device having an extraction part connected to the through hole and / or an electrically conducting portion through the through hole, partially or wholly manufactured by the manufacturing method of the present invention, and the like are exemplified. .

  In addition, the circuit board is not particularly limited, but specifically, a part or the whole manufactured by the manufacturing method of the present invention, the electrically conductive portion between both surfaces and / or multilayers through a through hole. A one-layer (single-sided) printed wiring board, a two-layer (double-sided) printed wiring board, a multilayer printed wiring board, or a flexible printed wiring board; a substrate and an electronic component that are partially or wholly manufactured by the manufacturing method of the present invention Examples include a one-layer (single-sided) printed wiring board, a two-layer (double-sided) printed wiring board, a multilayer printed wiring board, a flexible printed wiring board, and the like having an electrically conductive portion bonded to each other.

  In addition, the multilayer capacitor is not particularly limited, and specifically, a multilayer capacitor having an internal electrode and / or an external electrode, which is partially or wholly manufactured by the manufacturing method of the present invention, is exemplified. .

  In addition, the solid electrolytic capacitor is not particularly limited, and specific examples thereof include a solid electrolytic capacitor having a conductive thin film layer partially or wholly manufactured by the manufacturing method of the present invention as a cathode electrode layer. Is done.

  Further, the solar cell is not particularly limited, but specifically, a silicon-based solar cell having a light incident side electrode and / or a back side electrode manufactured partially or entirely by the manufacturing method of the present invention. Examples include batteries, compound semiconductor solar cells, dye-sensitized solar cells, and organic semiconductor solar cells.

  In addition, the secondary battery is not particularly limited, and specifically, a part or the whole manufactured by the manufacturing method of the present invention has an electrically conductive portion where the electrode tab and the electrode lead are joined. Examples include lithium secondary batteries and nickel-hydrogen secondary batteries.

  Further, the radio wave system recognition tag is not particularly limited, but specifically, it is selected from the group consisting of a conductive thin film, a wiring, and an electrode partially or wholly manufactured by the manufacturing method of the present invention. For example, a radio wave type recognition tag having an electrically conductive portion joined by one or two or more antennas and / or electronic components.

  Further, the electromagnetic wave shielding shield is not particularly limited, but specifically, a kind selected from the group consisting of a conductive thin film, a wiring, and an electrode partially or wholly manufactured by the manufacturing method of the present invention. Or the electromagnetic shielding shield etc. which have the electrical conduction | electrical_connection part which consists of 2 or more types are illustrated.

  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.

  In addition, in the following reference examples, the average particle diameter of the fine particles is randomly selected from three points in the field of view using a transmission electron microscope (TEM) or a scanning electron microscope (SEM) depending on the particle size. Select and shoot at an arbitrary magnification in the range of 50,000 to 1,000,000 times, select 100 particles in total from each photo, measure the diameter with a ruler, and divide the measurement magnification The particle diameter was calculated and obtained by arithmetically averaging these values. TEM manufactured by JEOL Ltd., trade name: JEM-2000FX, and SEM used by JEOL Ltd., trade name: JSM T220A.

Elemental analysis was measured by Perkin Elmer, fully automatic elemental analyzer, trade name: 2400II, and ¹ H-NMR was measured by Varian, trade name: Gemini-200.

  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 Inc.) unless otherwise specified.

[Reference Example 1] Preparation of copper formate fine particles.
To 40 g of ethanol, 2.24 g of copper formate powder (primary average particle size 21 μm) and 150 g of zirconia beads (made by Nikkato Co., Ltd., trade name: YZT ball, size: Φ0.1 mm) were added, and the stirring connected to a stirring motor. Using wings, 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 beads made of zirconia to obtain a copper formate fine particle dispersion.

  This copper formate fine particle dispersion was observed with an SEM, and the primary average particle diameter was determined to be 210 nm. Next, 1.68 g of copper formate fine particle powder was obtained by distilling off ethanol and excess water from the copper formate fine particle dispersion at a temperature not exceeding 60 ° C. under reduced pressure conditions.

[Reference Example 2] Preparation of silver fine particle dispersion.
To 10 g of aniline, 1.67 g of silver acetate was added and stirred at 40 ° C. for about 10 minutes until the solid was completely dissolved and became a homogeneous solution. Subsequently, a solution prepared by dissolving 0.37 g of sodium borohydride in 1.63 g of water was added dropwise at room temperature over 30 minutes. The mixture was further stirred at room temperature for 30 minutes and transferred to a separatory funnel under a nitrogen stream. After the phase-separated lower colorless and transparent aqueous phase was removed, washing with 10 g of ion-exchanged water and again removing the lower aqueous phase after phase separation yielded a black silver fine particle dispersion.

When this silver fine particle dispersion was observed with TEM and the average particle diameter was determined, it was 9.2 nm (standard deviation 4.2, coefficient of variation 46%). The silver fine particle dispersion was heated to 80 ° C. under reduced pressure (120 Pa) to remove distillate, thereby obtaining 2.19 g of silver fine particles. As a result of elemental analysis, the obtained silver fine particles were composed of 46% by weight of silver and 54% by weight of organic components, and the main component of the organic matter was aniline from the analysis result by ¹ H-NMR.

[Example 1] Preparation of conductive ink composition containing copper formate fine particles and n-octylamine.
To 68 g of tetrahydrofuran, 1.68 g of the copper formate fine particles (primary average particle size 210 nm) obtained in Reference Example 1 and 0.65 g of n-octylamine were added, and kneaded sufficiently until the dispersion was completely dispersed in a mortar. From this slurry-like mixture, tetrahydrofuran and excess water were distilled off at a temperature not exceeding 60 ° C. under reduced pressure conditions to prepare a paste-like conductive ink composition.

  The viscosity of the obtained conductive ink composition was 168 Pa · s, and as a result of elemental analysis, it contained 25.6 wt% copper, 36.8 wt% formic acid, 37.4 wt% n-octylamine. (Hereinafter, for the sake of brevity, this is referred to as “Paste A”).

[Example 2] Preparation of conductive ink composition containing copper formate fine particles, 2-ethylhexylamine, and terpineol.
Add 1.68 g of copper formate fine particles (primary average particle size 210 nm) obtained in Reference Example 1 to 0.6 g of tetrahydrofuran, 0.65 g of 2-ethylhexylamine, and 0.75 g of terpineol until 10 g of tetrahydrofuran is completely dispersed in the mortar. Kneaded thoroughly. From this slurry-like mixture, tetrahydrofuran and excess water were distilled off at a temperature not exceeding 60 ° C. under reduced pressure conditions to prepare a paste-like conductive ink composition.

  The viscosity of the obtained conductive ink composition was 72 Pa · s. As a result of elemental analysis, 20.8 wt% copper, 29.9 wt% formic acid, 23.1 wt% 2-ethylhexylamine, 26 Contained 1% by weight of terpineol (hereinafter referred to as "Paste B" for the sake of brevity).

Example 3 Preparation of a conductive ink composition containing copper formate fine particles, hexamethyleneimine, and silver fine particles.
To 10 g of n-hexane, 1.68 g of copper formate fine particles (primary average particle diameter 210 nm) obtained in Reference Example 1, 0.15 g of silver fine particles obtained in Reference Example 2, and 0.90 g of hexamethyleneimine were added, The mixture was sufficiently kneaded until it was completely dispersed in a mortar. The slurry-like mixture was distilled off hexane and excess water at a temperature not exceeding 60 ° C. under reduced pressure conditions to prepare a paste-like conductive ink composition.

  The resulting conductive ink composition had a viscosity of 144 Pa · s. As a result of elemental analysis, 22.8 wt% copper, 32.8 wt% formic acid, 37.3 wt% hexamethyleneimine, 4. It contained 2 wt% silver (hereinafter referred to as “Paste C” for the sake of brevity).

[Example 4] Preparation of conductive ink composition containing copper formate fine particles, n-hexanethiol, and palladium acetate.
To 10 g of tetrahydrofuran, 1.68 g of the copper formate fine particles (primary average particle size 210 nm) obtained in Reference Example 1, 0.15 g of palladium acetate, and 0.98 g of n-hexanethiol were added, and the mixture was completely dispersed in a mortar. It knead | mixed fully until it became. From this slurry-like mixture, tetrahydrofuran and excess water were distilled off at a temperature not exceeding 60 ° C. under reduced pressure conditions to prepare a paste-like conductive ink composition.

  The resulting conductive ink composition had a viscosity of 189 Pa · s. As a result of elemental analysis, 21.6 wt% copper, 31.1 wt% formic acid, 42.0 wt% n-hexanethiol, 2 It contained 0.7 wt% acetic acid and 3.0 wt% palladium (hereinafter referred to as "Paste D" for the sake of brevity).

Comparative Example 1 Preparation of a conductive ink composition containing copper formate and n-hexylamine.
To 10 g of tetrahydrofuran, 2.24 g of copper formate and 2.1 g of n-hexylamine were sequentially added. The mixture was stirred at room temperature for 10 minutes until it was completely dissolved to obtain a uniform solution. This solution was filtered through a 0.5 μm membrane filter, and then the tetrahydrofuran in the obtained filtrate was desolvated by concentration under reduced pressure to prepare a conductive ink composition.

  It was 4.9 mPa * s as a result of measuring the viscosity of the obtained electroconductive ink composition with the B-type viscosity meter (The Toki Sangyo company make, brand name: BL II). In addition, as a result of elemental analysis, it contained 17.6% by weight of copper, 25.3% by weight of formic acid, and 56.1% by weight of n-hexylamine. Referred to as "Paste E").

[Examples 5 to 8, Comparative Example 2] Printability evaluation, conductivity evaluation, and shape stability evaluation.
On a glass substrate, pastes A to D were subjected to a screen printing method (screen specification mesh number: 200, wire diameter: 40 μm, weave thickness: 115 μm, mesh opening: 87 μm, space ratio: 46.9%, paste permeation volume: 53.94 mg / cm ³ ) was applied to a glass substrate to form a uniform coating film having a width of 2 mm × a length of 30 mm and a film thickness of 54 μm.

  Next, the glass substrate on which these pastes were applied was subjected to heat treatment for 30 minutes in a heating furnace in which nitrogen gas was circulated at a flow rate of 6 L / min to obtain an electrically conductive portion. Each heating temperature is shown in Table 1.

形成された各電気的導通部位について、表面抵抗率を四探針抵抗測定機（三菱化学社製、商品名：ロレスタＧＰ）にて測定した。

About each formed electrical conduction site | part, the surface resistivity was measured with the four-point probe resistance measuring device (the Mitsubishi Chemical Corporation make, brand name: Loresta GP).

  Moreover, each formed electrical conduction site | part was cut | disconnected, the cross section was observed with the scanning electron microscope (SEM), and the average film thickness of each electrical conduction site | part was evaluated. 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, and 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 average film thickness at each electrically conducting portion.

The printability is evaluated by visually checking the shape of the printed pattern.
If there is no tearing, chipping or bleeding: ○,
If there is tear, chipping, or bleeding: ×,
It was evaluated.

  In addition, the electrical conductivity was evaluated by comparing the measured surface resistivity and the volume resistivity calculated from the average film thickness obtained from the observation result of the scanning electron microscope (SEM) at each electrically conductive portion. .

  Further, the shape stability was evaluated by the area change rate after the heat treatment from the application size at the time of applying each paste.

    Area change rate (%) = [(area after heat treatment / area during application) −1] × 100.

  The electrical conductivity was evaluated by comparing the volume resistivity calculated from the surface resistivity and the average film thickness obtained from the observation result of the scanning electron microscope (SEM) in each electrically conductive portion.

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

  As is clear from Table 1, in Examples 5 to 8, all of the conductive ink compositions of the present invention exhibited good printability, and no tearing, chipping or bleeding was observed. Moreover, regarding electroconductivity, favorable electroconductivity was shown and the shape stability before and behind heat processing was also excellent.

  On the other hand, in Comparative Example 2, the conductive ink composition, which was a solution in which copper formate was completely dissolved, had a low viscosity, so that the wiring could not be applied uniformly due to printing defects such as tearing, chipping, and bleeding. . Regarding conductivity, although the conductivity was not much different, the shape change before and after the heat treatment was large.

Claims (16)

One or more coordination compounds selected from the group consisting of copper salt fine particles (A) comprising a carboxylic acid having reducing power and copper ions, alkanethiols, aliphatic amines, aromatic amines, and cyclic amines (B) and one or two or more types of dispersion medium (D) selected from the group consisting of hexanol, terpineol, methyl-t-butyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, n-hexane, and γ-butyrolactone, and having a viscosity. A conductive ink composition having a range of 10 to 300 Pa · s. A copper salt composed of a carboxylic acid having a reducing power and a copper ion is selected from the group consisting of copper formate, copper hydroxyacetate, copper glyoxylate, copper lactate, copper oxalate, copper tartrate, copper malate, and copper citrate. The conductive ink composition according to claim 1, wherein the conductive ink composition is one kind or two or more kinds. 3. The conductive ink composition according to claim 1, wherein the primary average particle diameter of the copper salt fine particles (A) is in the range of 1 nm to 5 μm. A conductive ink composition according to any one of claims 1 to 3 is applied or filled in a desired portion of the base material to obtain electrical conduction, and the base material is heat-treated. The manufacturing method of the electrical conduction site. 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 manufacturing method of the electrically-conductive part of Claim 4 . The method for producing an electrically conductive portion according to claim 4 or 5 , wherein the temperature of the heat treatment is in the range of 60C to 300C. The method for manufacturing an electrically conductive portion according to any one of claims 4 to 6 , wherein heat treatment is performed in a non-oxidizing atmosphere. Electrical conduction site formed by the manufacturing method according to any one of claims 4 to 7. The process according to any one of claims 4 to 7, the image display device characterized by having a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, the light emitting device characterized by having a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, the circuit board characterized by having a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, a capacitor characterized in that it comprises a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, the solar cell characterized by having a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, a secondary battery characterized by having a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, Radio Frequency Identification tags, characterized in that it comprises a manufactured part or whole electrical conduction site. The process according to any one of claims 4 to 7, the electromagnetic wave shielding shielding, characterized in that it comprises a manufactured part or whole electrical conduction site.