WO2015147124A1 - Laminated body - Google Patents

Abstract

In the present invention, a laminated body is provided with a substrate and a metal silver layer formed on top of the substrate, and is configured so that the volume resistivity of the metal silver layer is no more than 5μΩ·cm, and the surface roughness of the metal silver layer is no more than 70nm.

Description

Laminated body

The present invention relates to a laminate.
This application claims priority based on Japanese Patent Application No. 2014-070354 for which it applied to Japan on March 28, 2014, and uses the content here.

Metallic silver is widely used as a recording material, a printing plate material, and a highly conductive material because of its excellent conductivity.
So far, as a general method for producing metallic silver, for example, a method using organic acid silver such as silver behenate, silver stearate, silver α-ketocarboxylate and silver β-ketocarboxylate has been disclosed. For example, silver β-ketocarboxylate quickly forms metallic silver even when heat-treated at a low temperature of about 210 ° C. or lower (see Patent Document 1). Utilizing such excellent characteristics, a method of forming silver metal by dissolving silver β-ketocarboxylate in a solvent to prepare a silver ink composition, adhering the silver ink composition onto a substrate and heat-treating it Is disclosed (see Patent Document 1).

However, for example, when metallic silver is applied to an antenna of an electronic device or the like, metallic silver having a surface roughness comparable to that of metallic silver described in Patent Document 1 and exhibiting a reduced volume resistivity is desired. May be.

JP 2014-49644 A

Therefore, the present invention is a laminate comprising a base material and a metallic silver layer formed on the base material, and can be produced without performing a heat treatment at a high temperature. An object of the present invention is to provide a laminate exhibiting sufficiently reduced volume resistivity and surface roughness with good reproducibility.

The present invention comprises a base material and a metal silver layer formed on the base material, the volume resistivity of the metal silver layer is 5 μΩ · cm or less, and the surface roughness of the metal silver layer is 70 nm or less. A laminate is provided.

The metallic silver layer is formed by solidifying a silver ink composition deposited on the substrate, and the silver ink composition has a carboxylic acid having a group represented by the formula “—COOAg”. One or more nitrogen-containing compounds selected from the group consisting of silver, an amine compound having 25 or less carbon atoms, a quaternary ammonium salt having 25 or less carbon atoms, ammonia and an ammonium salt obtained by reacting the amine compound or ammonia with an acid. A mixture of the compound and one or both of oxalic acid, hydrazine and one or more reducing compounds selected from the group consisting of compounds represented by the following general formula (5), and alcohol, in a stirring tank It may be manufactured by a manufacturing method including a step of stirring by rotating the stirring blade.
HC (═O) —R ²¹ (5)
(Wherein R ²¹ represents an alkyl group having 20 or less carbon atoms, an alkoxy group, or an N, N-dialkylamino group, a hydroxyl group, or an amino group.)

The stirring blade includes a drive shaft, a forced flow generating blade portion having an outer side that rotates and moves in the vicinity of the inner peripheral surface of the stirring tank, and a connecting portion that connects the drive shaft and the forced flow generating blade portion. It may be provided.
The substrate may have a thickness of 10 to 5000 μm.
The metal silver layer may have a thickness of 0.5 to 20 μm.

The laminate of the present invention comprises a substrate and a metal silver layer formed on the substrate, and can be produced without performing a heat treatment at a high temperature, and the metal silver layer is sufficiently reproducible. Shows the reduced volume resistivity and surface roughness.

It is a schematic diagram which shows the stirring blade of an anchor shape. It is a schematic diagram which shows the propeller-shaped stirring blade. It is a schematic diagram which shows the other stirring blade of an anchor shape.

Preferred examples of the laminate of the present invention will be described below. However, the present invention is not limited to these examples. For example, additions, omissions, substitutions, and other changes (amount, number, position, size, etc.) are possible without departing from the spirit of the present invention. It is.

<Laminate>
The present invention comprises a base material and a metal silver layer formed on the base material, the volume resistivity of the metal silver layer is 5 μΩ · cm or less, and the surface roughness of the metal silver layer is 70 nm or less. A laminate is provided.

The metal silver layer of the laminate is mainly composed of metal silver. Here, “having metallic silver as a main component” means that the ratio of metallic silver is sufficiently high so that it can be regarded as being composed solely of metallic silver. For example, the metallic silver in the metallic silver layer The ratio is preferably 99% by mass or more. The upper limit of the ratio of the metallic silver in the metallic silver layer is, for example, 99.9% by mass, 99.8% by mass, 99.7% by mass, 99.6% by mass, 99.5% by mass, 99.4% by mass. %, 99.3% by mass, 99.2% by mass, and 99.1% by mass.

The metallic silver layer can be formed, for example, by attaching and solidifying a silver ink composition described later on a substrate. In the present specification, “solidification of the silver ink composition” means reducing or removing volatile components from the silver ink composition, and appropriately performing post-treatment such as drying treatment or heating (firing) treatment. You may choose. The heat treatment may be performed also as a drying treatment.
The substrate is preferably in the form of a film or a sheet, and preferably has a thickness of 10 to 5000 μm.

The material of the base material may be appropriately selected according to the purpose and is not particularly limited, but specific examples of preferable materials include polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), and polyvinylidene chloride ( PVDC), polymethylpentene (PMP), polycycloolefin, polystyrene (PS), polyvinyl acetate (PVAc), acrylic resin such as polymethyl methacrylate (PMMA), AS resin, ABS resin, polyamide (PA), polyimide , Polyamideimide (PAI), polyacetal, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), polyetherketone (PEK), polyetheretherketone (PEEK), polycarbonate (PC), polyurethane, polyphenylene ether (PPE), modified polyphenylene ether (m- PPE), polyarylate, epoxy resin, melamine resin, phenol resin, urea resin, and other synthetic resins can be exemplified.
In addition to the above, the material of the substrate can be exemplified by ceramics such as glass and silicon, and paper.
The base material may be made of two or more kinds of materials such as glass epoxy resin and polymer alloy.

The substrate may be composed of a single layer, or may be composed of two or more layers. When a base material consists of multiple layers, these multiple layers may be the same as or different from each other. That is, all the layers may be the same, all the layers may be different, or only some of the layers may be different. And when several layers differ from each other, the combination of these several layers is not specifically limited. Here, the plurality of layers being different from each other means that at least one of the material and the thickness of each layer is different from each other.
In addition, when a base material consists of multiple layers, it is good to make it the total thickness of each layer be the thickness of said preferable base material.

A silver ink composition can be made to adhere on a base material by well-known methods, such as a printing method, the apply | coating method, and the immersion method, for example.
Examples of the printing method include screen printing method, flexographic printing method, offset printing method, dip printing method, ink jet printing method, dispenser printing method, gravure printing method, gravure offset printing method, pad printing method and the like.
Examples of the coating method include spin coaters, air knife coaters, curtain coaters, die coaters, blade coaters, roll coaters, gate roll coaters, bar coaters, rod coaters, gravure coaters, and other methods such as wire bars. It can be illustrated.

The silver ink composition may be dried by a known method. For example, the silver ink composition may be dried under normal pressure, reduced pressure, or air blowing conditions, and may be performed in the air or in an inert gas atmosphere. Good. Also, the drying temperature is not particularly limited, and may be either heat drying or room temperature drying. As a preferable drying method when the heat treatment is unnecessary, a method of drying in the atmosphere at 18 to 30 ° C. can be exemplified.

When the silver ink composition is heated (baked), the conditions may be adjusted as appropriate according to the type of compounding component of the silver ink composition. Usually, the heating temperature is preferably 60 to 200 ° C, more preferably 70 to 180 ° C. The heating time may be adjusted according to the heating temperature, but usually it is preferably 0.2 to 12 hours, more preferably 0.4 to 10 hours. Among the metal silver forming materials, the silver carboxylate, particularly silver β-ketocarboxylate (1) is different from the metal silver forming material such as silver oxide, for example, using a reducing agent known in the art. Even if not, it decomposes at low temperature. Reflecting such decomposition temperature, the silver ink composition can form metallic silver at an extremely lower temperature than the conventional one as described above.
When the silver ink composition is attached to a substrate having low heat resistance and heated (baked), the heating temperature is preferably less than 130 ° C, more preferably 125 ° C or less, and 120 ° C. It is particularly preferred that

The method for heat treatment of the silver ink composition is not particularly limited, and for example, heating by an electric furnace, heating by a thermal head, heating by far infrared irradiation, or the like can be performed. Further, the heat treatment of the silver ink composition may be performed in the air, in an inert gas atmosphere, or may be performed under humidified conditions. And you may carry out under any of normal pressure, pressure reduction, and pressurization.

In this specification, “humidification” means that the humidity is artificially increased unless otherwise specified, and the relative humidity is preferably 5% or more. At the time of heat treatment, since the humidity in the treatment environment becomes extremely low due to the high treatment temperature, it can be said that the relative humidity of 5% is clearly artificially increased.

The relative humidity when the heat treatment of the silver ink composition is performed under humidified conditions is preferably 10% or more, more preferably 30% or more, further preferably 50% or more, and 70%. It is particularly preferable that it be 90% or more, or 100%. And you may perform the heat processing under humidification conditions by spraying the high pressure steam heated to 100 degreeC or more. Thus, by heat-processing under humidification conditions, highly pure metallic silver can be formed in a short time.

The heat treatment of the silver ink composition may be performed in two stages. For example, in the first stage heat treatment, there is exemplified a method in which the silver ink composition is mainly dried rather than the formation of metal silver, and the formation of metal silver is completed in the second stage heat treatment.
In the first-stage heat treatment, the heating temperature may be appropriately adjusted according to the type of compounding component of the silver ink composition, but is preferably 60 to 110 ° C, more preferably 70 to 90 ° C. preferable. The heating time may be adjusted according to the heating temperature, but it is usually preferably 5 seconds to 12 hours, and more preferably 30 seconds to 2 hours.
In the second stage heat treatment, the heating temperature may be appropriately adjusted according to the type of compounding component of the silver ink composition so that metallic silver is favorably formed, but it should be 60 to 200 ° C. Preferably, it is 70 to 180 ° C. The heating time may be adjusted according to the heating temperature, but it is usually preferably 1 minute to 12 hours, and more preferably 1 minute to 10 hours.
When the silver ink composition is attached to a substrate having low heat resistance and is heated (baked), the heating temperature in the first stage and second stage heat treatment is preferably less than 130 ° C., The temperature is more preferably 125 ° C. or lower, and particularly preferably 120 ° C. or lower.

When heat treatment under humidified conditions is employed, the heat treatment of the silver ink composition is not the formation of metallic silver as described above under non-humidified conditions in the first stage heat treatment. It is particularly preferable to perform drying in a two-stage method in which the formation of metallic silver is performed to the end as described above under humidified conditions in the second-stage heat treatment.
In the present specification, “non-humidification” means that the above “humidification” is not performed, that is, the humidity is not artificially increased, and preferably the relative humidity is less than 5%. .

When the above heat treatment is performed by a two-stage method, the heating temperature during the heat treatment under the first non-humidifying condition is preferably 60 to 110 ° C., more preferably 70 to 90 ° C. preferable. The heating time is preferably 5 seconds to 3 hours, more preferably 30 seconds to 2 hours, and particularly preferably 30 seconds to 1 hour.
When the above heat treatment is performed by a two-stage method, the heating temperature during the heat treatment under the second-stage humidification condition is preferably 60 to 180 ° C, more preferably 70 to 160 ° C. . The heating time is preferably 1 minute to 2 hours, more preferably 1 minute to 1 hour, and particularly preferably 1 minute to 30 minutes.
When the silver ink composition is attached to a substrate having low heat resistance and is heated (baked), the heat treatment under the first stage non-humidifying condition and the heat treatment under the second stage humidifying condition are performed. The heating temperature in is preferably less than 130 ° C., more preferably 125 ° C. or less, and particularly preferably 120 ° C. or less.

However, the above heat treatment conditions are merely examples. When heat-treating the silver ink composition at a particularly low temperature, for example, the temperature during the heat treatment can be preferably 100 ° C. or lower, more preferably 90 ° C. or lower. Although the lower limit of the temperature at the time of heat processing is not specifically limited as long as metallic silver can be formed efficiently, it is preferable that it is 50 degreeC.
In addition, the heating time may be appropriately adjusted according to the heating temperature, and may be, for example, 0.1 to 6 hours.

The laminate of the present invention can sufficiently reduce the thickness of the metal silver layer. The thickness of the metallic silver layer is preferably 20 μm or less, more preferably 10 μm or less, and particularly preferably 2 μm or less.
The lower limit of the thickness of the metallic silver layer is not particularly limited, but the thickness of the metallic silver layer is preferably 0.5 μm or more, more preferably 0.7 μm or more, and particularly preferably 0.9 μm or more. It is. A metal silver layer has more excellent electroconductivity because the thickness of a metal silver layer is more than the said lower limit.

When the metal silver layer is linear, the laminate of the present invention can sufficiently narrow the line width. For example, the line width of the metal silver layer in the cross section in the direction perpendicular to the line length direction of the linear metal silver layer is preferably 1000 μm or less, more preferably 800 μm or less, and particularly preferably 600 μm or less. Is possible.
The lower limit of the line width of the metallic silver layer in the cross section is not particularly limited, but the line width is preferably 0.5 μm or more, more preferably 1 μm or more, and particularly preferably 2 μm or more.
However, what is shown here is an example, and the line width may be appropriately selected according to the use of the laminate.

The volume resistivity of the metallic silver layer of the laminate is sufficiently reduced. The volume resistivity of the metallic silver layer is 5 μΩ · cm or less, preferably 4.9 μΩ · cm or less, and can be 4.8 μΩ · cm or less.
The lower limit of the volume resistivity of the metallic silver layer is preferably as small as possible, and is not particularly limited. For example, it can be preferably 3 μΩ · cm.
Here, the volume resistivity of the metal silver layer is determined by measuring the line resistance value R (Ω), the cross-sectional area A (cm ² ), and the line length L (cm) of the metal silver layer, and the formula “ρ = R × A / L "can be calculated as volume resistivity ρ (Ω · cm).

Moreover, the surface roughness of the metal silver layer of the laminate is sufficiently reduced. The surface roughness of the metallic silver layer is 70 nm or less, preferably 69 nm or less, and can be 65 nm or less or 60 nm or less.
The lower limit of the surface roughness of the metallic silver layer is not particularly limited, but is preferably 35 nm, for example.
In the present specification, “surface roughness” means arithmetic average roughness (Ra), and only the reference length is extracted from the roughness curve in the direction of the average line, and the direction of the average line of the extracted portion. The value obtained by the following formula is displayed in nanometer (nm) units when the X-axis is taken along the Y-axis in the direction of the vertical magnification and the roughness curve is expressed as y = f (x) It is. Hereinafter, this surface roughness may be referred to as “surface roughness Ra”.

The laminate according to the present invention can be manufactured without performing heat treatment at high temperature, the thickness of the metal silver layer can be sufficiently reduced, and the volume resistivity and surface roughness are sufficiently reduced. Therefore, it is particularly suitable as a wiring board for communication equipment.

<Silver ink composition>
The silver ink composition preferably contains a metallic silver forming material.
The metal silver forming material may be any material that has silver atoms (elements) and generates metallic silver by structural change such as decomposition, and is a silver salt, a silver complex, an organic silver compound (a compound having a silver-carbon bond) ) Etc. can be illustrated. The silver salt and the silver complex may be either a silver compound having an organic group or a silver compound having no organic group. Among these, the metal silver forming material is preferably a silver salt.
By using a metallic silver forming material, metallic silver is generated from the material, and a conductor containing the metallic silver is formed.

The material for forming metallic silver is preferably silver carboxylate having a group represented by the formula “—COOAg” (hereinafter sometimes simply referred to as “silver carboxylate”).

The silver ink composition preferably contains silver carboxylate, a nitrogen-containing compound, and one or both of a reducing compound and an alcohol, and contains silver carboxylate, a nitrogen-containing compound, and a reducing compound. More preferably, and those obtained by blending silver carboxylate, nitrogen-containing compound, reducing compound and alcohol.

The nitrogen-containing compound is one or more selected from the group consisting of an amine compound having 25 or less carbon atoms, a quaternary ammonium salt having 25 or less carbon atoms, ammonia and an ammonium salt obtained by reacting the amine compound or ammonia with an acid. It is.

The reducing compound is at least one selected from the group consisting of oxalic acid, hydrazine and a compound represented by the following general formula (5) (hereinafter sometimes abbreviated as “compound (5)”).
By blending the reducing compound, the silver ink composition can more easily form metallic silver. For example, metallic silver (conductor) having sufficient conductivity can be formed even by heat treatment at a low temperature.
HC (= O) -R ²¹ (5)
(Wherein R ²¹ represents an alkyl group having 20 or less carbon atoms, an alkoxy group, or an N, N-dialkylamino group, a hydroxyl group, or an amino group.)

[Silver carboxylate]
In this invention, silver carboxylate may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.
The silver carboxylate is not particularly limited as long as it has a group represented by the formula “—COOAg”. For example, the number of groups represented by the formula “—COOAg” may be one, or two or more. Further, the position of the group represented by the formula “—COOAg” in the silver carboxylate is not particularly limited.

The silver carboxylate is represented by the following general formula (1) β-ketocarboxylate silver (hereinafter sometimes abbreviated as “β-ketocarboxylate (1)”) and the following general formula (4). It is preferably one or more selected from the group consisting of silver carboxylates (hereinafter sometimes abbreviated as “silver carboxylate (4)”).
In this specification, the simple description of “silver carboxylate” is not limited to “silver β-ketocarboxylate (1)” and “silver carboxylate (4)”, unless otherwise specified. It is intended to mean “silver carboxylate having a group represented by the formula“ —COOAg ””.

(Wherein R represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms in which one or more hydrogen atoms may be substituted with a substituent, a phenyl group, a hydroxyl group, an amino group, or a group represented by the general formula “R ¹ -CY ¹ _2- "," CY ¹ _3- "," R ¹ -CHY ^1- "," R ² O- "," R ⁵ R ⁴ N- "," (R ³ O) ₂ CY ^1- "or" R ⁶ —C (═O) —CY ¹ ₂ — ”;
Y ¹ is each independently a fluorine atom, a chlorine atom, a bromine atom or a hydrogen atom; R ¹ is an aliphatic hydrocarbon group having 1 to 19 carbon atoms or a phenyl group; R ² is an aliphatic having 1 to 20 carbon atoms R ³ is an aliphatic hydrocarbon group having 1 to 16 carbon atoms; R ⁴ and R ⁵ are each independently an aliphatic hydrocarbon group having 1 to 18 carbon atoms; R ⁶ is An aliphatic hydrocarbon group having 1 to 19 carbon atoms, a hydroxyl group or a group represented by the formula “AgO—”;
X ¹ is independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a phenyl group or benzyl group in which one or more hydrogen atoms may be substituted with a substituent, a cyano group, N -Phthaloyl-3-aminopropyl group, 2-ethoxyvinyl group, or “R ⁷ O—”, “R ⁷ S—”, “R ⁷ —C (═O) —” or “R ⁷ —C ( ═O) —O— ”;
R ⁷ is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a thienyl group, or a phenyl group or diphenyl group in which one or more hydrogen atoms may be substituted with a substituent. )

(Wherein R ⁸ is an aliphatic hydrocarbon group having 1 to 19 carbon atoms, a carboxy group, or a group represented by the formula “—C (═O) —OAg”, wherein the aliphatic hydrocarbon group is a methylene group. And one or more of the methylene groups may be substituted with a carbonyl group.)

(Silver β-ketocarboxylate (1))
The silver β-ketocarboxylate (1) is represented by the general formula (1).
In the formula, R is an aliphatic hydrocarbon group having 1 to 20 carbon atoms, a phenyl group, a hydroxyl group, an amino group, or a group represented by the general formula “R ¹ -CY ¹ ” in which one or more hydrogen atoms may be substituted with a substituent. _2- "," CY ¹ _3- "," R ¹ -CHY ^1- "," R ² O- "," R ⁵ R ⁴ N- "," (R ³ O) ₂ CY ^1- "or" R ⁶ —C (═O) —CY ¹ ₂ — ”.

The aliphatic hydrocarbon group having 1 to 20 carbon atoms in R may be any of linear, branched and cyclic (aliphatic cyclic group), and may be monocyclic or polycyclic when cyclic. . Further, the aliphatic hydrocarbon group may be either a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, and more preferably 1 to 6 carbon atoms. Preferred examples of the aliphatic hydrocarbon group for R include an alkyl group, an alkenyl group, and an alkynyl group.

Examples of the linear or branched alkyl group in R include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n -Pentyl group, isopentyl group, neopentyl group, tert-pentyl group, 1-methylbutyl group, 2-methylbutyl group, n-hexyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4- Methylpentyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, 3,3-dimethylbutyl group, 2,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 3-ethylbutyl group 1-ethyl-1-methylpropyl group, n-heptyl group, 1-methylhexyl group, 2-methylhexyl group, 3-methylhexyl group, -Methylhexyl group, 5-methylhexyl group, 1,1-dimethylpentyl group, 2,2-dimethylpentyl group, 2,3-dimethylpentyl group, 2,4-dimethylpentyl group, 3,3-dimethylpentyl group 4,4-dimethylpentyl group, 1-ethylpentyl group, 2-ethylpentyl group, 3-ethylpentyl group, 4-ethylpentyl group, 2,2,3-trimethylbutyl group, 1-propylbutyl group, n -Octyl, isooctyl, 1-methylheptyl, 2-methylheptyl, 3-methylheptyl, 4-methylheptyl, 5-methylheptyl, 1-ethylhexyl, 2-ethylhexyl, 3-ethylhexyl Group, 4-ethylhexyl group, 5-ethylhexyl group, 1,1-dimethylhexyl group, 2,2-dimethylhexyl group, 3, -Dimethylhexyl group, 4,4-dimethylhexyl group, 5,5-dimethylhexyl group, 1-propylpentyl group, 2-propylpentyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group And pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group and icosyl group.
Examples of the cyclic alkyl group in R include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, norbornyl group, isobornyl group, 1-adamantyl group, 2- Examples thereof include an adamantyl group and a tricyclodecyl group.

Examples of the alkenyl group in R include a vinyl group (ethenyl group, —CH═CH ₂ ), an allyl group (2-propenyl group, —CH ₂ —CH═CH ₂ ), and a 1-propenyl group (—CH═CH—CH). ₃ ), isopropenyl group (—C (CH ₃ ) ═CH ₂ ), 1-butenyl group (—CH═CH—CH ₂ —CH ₃ ), 2-butenyl group (—CH ₂ —CH═CH—CH ₃₎ ), 3-butenyl group (—CH ₂ —CH ₂ —CH═CH ₂ ), cyclohexenyl group, cyclopentenyl group and the like, one single bond (C—C) between the carbon atoms of the alkyl group in R Is a group in which is substituted with a double bond (C═C).
As the alkynyl group in R, one single bond (C—C) between carbon atoms of the alkyl group in R, such as ethynyl group (—C≡CH), propargyl group (—CH ₂ —C≡CH), etc. ) Is substituted with a triple bond (C≡C).

In the aliphatic hydrocarbon group having 1 to 20 carbon atoms in R, one or more hydrogen atoms may be substituted with a substituent, and preferred examples of the substituent include a fluorine atom, a chlorine atom, and a bromine atom. . Moreover, the number and position of substituents are not particularly limited. When the number of substituents is plural, the plural substituents may be the same as or different from each other. That is, all the substituents may be the same, all the substituents may be different, or only some of the substituents may be different.

In the phenyl group in R, one or more hydrogen atoms may be substituted with a substituent. Preferred examples of the substituent include a saturated or unsaturated monovalent aliphatic hydrocarbon group having 1 to 16 carbon atoms. A monovalent group formed by bonding the aliphatic hydrocarbon group to an oxygen atom, a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group (—OH), a cyano group (—C≡N), a phenoxy group (—O—), C ₆ H ₅ ) and the like can be exemplified, and the number and position of substituents are not particularly limited. When the number of substituents is plural, the plural substituents may be the same as or different from each other.
Examples of the aliphatic hydrocarbon group that is a substituent include the same aliphatic hydrocarbon groups as those described above for R except that the number of carbon atoms is 1 to 16.

Y ^{1 in} R is independently a fluorine atom, a chlorine atom, a bromine atom or a hydrogen atom. In the general formulas “R ¹ —CY ¹ ₂ —”, “CY ¹ ₃ —” and “R ⁶ —C (═O) —CY ¹ ₂ —”, a plurality of Y ¹ may be the same as each other. May be different.

R ¹ in R is an aliphatic hydrocarbon group having 1 to 19 carbon atoms or a phenyl group (C ₆ H ₅ —), and the aliphatic hydrocarbon group in R ¹ has 1 to 19 carbon atoms. Except for this point, the same aliphatic hydrocarbon groups as those in R can be exemplified.
R ² in R is an aliphatic hydrocarbon group having 1 to 20 carbon atoms, and examples thereof are the same as the aliphatic hydrocarbon group in R.
R ³ in R is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, and examples thereof are the same as the aliphatic hydrocarbon group in R except that the carbon number is 1 to 16.
R ⁴ and R ⁵ in R are each independently an aliphatic hydrocarbon group having 1 to 18 carbon atoms. That is, R ⁴ and R ⁵ may be the same as or different from each other, and examples thereof are the same as the aliphatic hydrocarbon group for R except that the number of carbon atoms is 1 to 18.
R ⁶ in R is an aliphatic hydrocarbon group having 1 to 19 carbon atoms, a hydroxyl group or a group represented by the formula “AgO—”. The aliphatic hydrocarbon group in R ⁶ has 1 to Except for being 19, the same aliphatic hydrocarbon groups as those described above for R can be exemplified.

Among them, R is a linear or branched alkyl group, a group represented by the general formula “R ⁶ —C (═O) —CY ¹ ₂ —”, a hydroxyl group, or a phenyl group. preferable. Then, R ⁶ represents a linear or branched alkyl group, or a group represented by a hydroxyl group or a formula "AgO-".

In the general formula (1), each X ¹ independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a phenyl group in which one or more hydrogen atoms may be substituted with a substituent, or A benzyl group (C ₆ H ₅ —CH ₂ —), a cyano group, an N-phthaloyl-3-aminopropyl group, a 2-ethoxyvinyl group (C ₂ H ₅ —O—CH═CH—), or the general formula “R ⁷ O— ”,“ R ⁷ S— ”,“ R ⁷ —C (═O) — ”or“ R ⁷ —C (═O) —O— ”.
Examples of the aliphatic hydrocarbon group having 1 to 20 carbon atoms in X ¹ include those similar to the aliphatic hydrocarbon group in R.

Examples of the halogen atom in X ¹ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In the phenyl group and benzyl group in X ¹ , one or more hydrogen atoms may be substituted with a substituent. Preferred examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), A nitro group (—NO ₂ ) and the like can be exemplified, and the number and position of substituents are not particularly limited. When the number of substituents is plural, the plural substituents may be the same as or different from each other.

R ⁷ in X ¹ represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a thienyl group (C ₄ H ₃ S—), a phenyl group in which one or more hydrogen atoms may be substituted with a substituent, or A diphenyl group (biphenyl group, C ₆ H ₅ —C ₆ H ₄ —); Examples of the aliphatic hydrocarbon group for R ⁷ include those similar to the aliphatic hydrocarbon group for R except that the aliphatic hydrocarbon group has 1 to 10 carbon atoms. Further, examples of the substituent of the phenyl group and a diphenyl group in R ^7, halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom) can be exemplified the like, the number and position of the substituent is not particularly limited. When the number of substituents is plural, the plural substituents may be the same as or different from each other.
When R ⁷ is a thienyl group or a diphenyl group, there are no particular limitations on the bonding position of these groups with an adjacent group or atom (oxygen atom, sulfur atom, carbonyl group, carbonyloxy group) in X ¹ . For example, the thienyl group may be either a 2-thienyl group or a 3-thienyl group.

In the general formula (1), two X ^{1 s} may be bonded as one group through a double bond with a carbon atom sandwiched between two carbonyl groups. Examples thereof include a group represented by the formula “═CH—C ₆ H ₄ —NO ₂ ”.

X ¹ is preferably a hydrogen atom, a linear or branched alkyl group, a benzyl group, or a group represented by the general formula “R ⁷ —C (═O) —” among the above. It is preferable that at least one X ¹ is a hydrogen atom.

Silver β-ketocarboxylate (1) is silver 2-methylacetoacetate (CH ₃ —C (═O) —CH (CH ₃ ) —C (═O) —OAg), silver acetoacetate (CH ₃ —C (= O) —CH ₂ —C (═O) —OAg), silver 2-ethylacetoacetate (CH ₃ —C (═O) —CH (CH ₂ CH ₃ ) —C (═O) —OAg), silver propionyl acetate (CH ₃ CH ₂ —C (═O) —CH ₂ —C (═O) —OAg), silver isobutyryl acetate ((CH ₃ ) ₂ CH—C (═O) —CH ₂ —C (═O) — OAg), silver pivaloyl acetate ((CH ₃ ) ₃ C—C (═O) —CH ₂ —C (═O) —OAg), silver caproyl acetate (CH ₃ (CH ₂ ) ₃ CH ₂ —C (═O ) —CH ₂ —C (═O) —OAg), silver 2-n-butylacetoacetate (CH ₃ —C (═O) —CH (C H ₂ CH ₂ CH ₂ CH ₃ ) —C (═O) —OAg), silver 2-benzylacetoacetate (CH ₃ —C (═O) —CH (CH ₂ C ₆ H ₅ ) —C (═O) —OAg), silver benzoyl acetate (C ₆ H ₅ —C (═O) —CH ₂ —C (═O) —OAg), silver pivaloyl acetoacetate ((CH ₃ ) ₃ C—C (═O) —CH ₂ —C (═O) —CH ₂ —C (═O) —OAg), silver isobutyrylacetoacetate ((CH ₃ ) ₂ CH—C (═O) —CH ₂ —C (═O) —CH ₂ -C (= O) -OAg), silver 2-acetylpivaloyl acetate ((CH ₃ ) ₃ CC (= O) -CH (-C (= O) -CH ₃ ) -C (= O) -OAg), 2- acetyl isobutyryl silver acetate _{((CH 3) 2 CH-} C (= O) -CH (-C (= O) -CH 3) -C (= O) - Ag), or is preferably acetone dicarboxylic silver _{(AgO-C (= O)} -CH 2 -C (= O) -CH 2 -C (= O) -OAg).

Β-ketocarboxylate (1) can further reduce the concentration of the remaining raw materials and impurities in the conductor (metal silver) formed by post-treatment such as drying treatment or heating (firing) treatment. The smaller the raw materials and impurities, for example, the better the contact between the formed metal silvers, the easier the conduction, and the lower the resistivity.

As will be described later, silver β-ketocarboxylate (1) is decomposed at a low temperature of preferably 60 to 210 ° C., more preferably 60 to 200 ° C. without using a reducing compound known in the art. It is possible to form metallic silver. And by using together with a reducing compound, it decomposes | disassembles at lower temperature and forms metallic silver. The reducing compound will be described later.

In the present invention, silver β-ketocarboxylate (1) may be used alone or in combination of two or more. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.

(Silver carboxylate (4))
The silver carboxylate (4) is represented by the general formula (4).
In the formula, R ⁸ is an aliphatic hydrocarbon group having 1 to 19 carbon atoms, a carboxy group (—COOH), or a group represented by the formula “—C (═O) —OAg”.
Examples of the aliphatic hydrocarbon group for R ⁸ include those similar to the aliphatic hydrocarbon group for R except that the aliphatic hydrocarbon group has 1 to 19 carbon atoms. However, the aliphatic hydrocarbon group for R ⁸ preferably has 1 to 15 carbon atoms, and more preferably 1 to 10 carbon atoms.

When the aliphatic hydrocarbon group for R ⁸ has a methylene group (—CH ₂ —), one or more of the methylene groups may be substituted with a carbonyl group. The number and position of the methylene groups that may be substituted with a carbonyl group are not particularly limited, and all methylene groups may be substituted with a carbonyl group. Here, the “methylene group” is not only a single group represented by the formula “—CH ₂ —” but also one of alkylene groups in which a plurality of groups represented by the formula “—CH ₂ —” are linked. And a group represented by the formula “—CH ₂ —”.

Silver carboxylate (4) includes silver pyruvate (CH ₃ —C (═O) —C (═O) —OAg), silver acetate (CH ₃ —C (═O) —OAg), silver butyrate (CH ₃ — (CH ₂ ) ₂ —C (═O) —OAg), silver isobutyrate ((CH ₃ ) ₂ CH—C (═O) —OAg), silver 2-ethylhexanoate (CH ₃ — (CH ₂ ) ₃ —CH (CH ₂ CH ₃ ) —C (═O) —OAg), silver neodecanoate (CH ₃ — (CH ₂ ) ₅ —C (CH ₃ ) ₂ —C (═O) —OAg), Shu It is preferably silver oxide (AgO—C (═O) —C (═O) —OAg) or silver malonate (AgO—C (═O) —CH ₂ —C (═O) —OAg). Further, silver oxalate (AgO—C (═O) —C (═O) —OAg) and silver malonate (AgO—C (═O) —CH ₂ —C (═O) —OAg) Of the groups represented by the formula “—COOAg”, one of the groups represented by the formula “—COOH” (HO—C (═O) —C (═O) —OAg, HO) Also preferred is —C (═O) —CH ₂ —C (═O) —OAg).

Similarly to the silver β-ketocarboxylate (1), the silver carboxylate (4) is also used for the remaining raw materials and impurities in the conductor (metal silver) formed by post-treatment such as drying treatment or heating (firing) treatment. The concentration can be further reduced. And by using together with a reducing compound, it decomposes | disassembles at lower temperature and forms metallic silver.

In the present invention, the silver carboxylate (4) may be used alone or in combination of two or more. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.

The silver carboxylate is silver 2-methylacetoacetate, silver acetoacetate, silver 2-ethylacetoacetate, silver propionylacetate, silver isobutyrylacetate, silver pivaloylacetate, silver caproylacetate, silver 2-n-butylacetoacetate, 2-benzylacetoacetate Silver acetate, silver benzoyl acetate, silver pivaloyl acetoacetate, silver isobutyryl acetoacetate, silver acetone dicarboxylate, silver pyruvate, silver acetate, silver butyrate, silver isobutyrate, silver 2-ethylhexanoate, silver neodecanoate, silver It is preferably at least one selected from the group consisting of silver oxide and silver malonate.
Among these silver carboxylates, silver 2-methylacetoacetate and silver acetoacetate are excellent in compatibility with a nitrogen-containing compound (particularly an amine compound) described later, and are particularly suitable for increasing the concentration of silver ink compositions. It is mentioned as a thing.

In the silver ink composition, the content of silver derived from the metal silver forming material is preferably 5% by mass or more, and more preferably 10% by mass or more. By being in such a range, the formed conductor (metal silver) becomes superior in quality. The upper limit of the silver content is not particularly limited as long as the effects of the present invention are not impaired, but it is preferably 25% by mass in consideration of handling properties and the like.
In the present specification, “silver derived from a metallic silver forming material” means silver in the metallic silver forming material blended during the production of the silver ink composition, unless otherwise specified. It is a concept that includes both silver constituting the metal silver forming material after blending, and silver and silver itself in the decomposition product generated by decomposition of the metal silver forming material after blending.

[Nitrogen-containing compounds]
The nitrogen-containing compound is an amine compound having 25 or less carbon atoms (hereinafter sometimes abbreviated as “amine compound”), a quaternary ammonium salt having 25 or less carbon atoms (hereinafter abbreviated as “quaternary ammonium salt”). Ammonia, an ammonium salt formed by reacting an amine compound having 25 or less carbon atoms with an acid (hereinafter sometimes abbreviated as “ammonium salt derived from an amine compound”), and ammonia reacting with an acid. Is one or more selected from the group consisting of ammonium salts (hereinafter sometimes abbreviated as “ammonium salts derived from ammonia”). That is, the nitrogen-containing compound to be blended may be only one kind, or two or more kinds. When two or more kinds are used in combination, the combination and ratio can be arbitrarily adjusted.

(Amine compound, quaternary ammonium salt)
The amine compound has 1 to 25 carbon atoms, and may be any of primary amine, secondary amine, and tertiary amine. The quaternary ammonium salt has 4 to 25 carbon atoms. The amine compound and the quaternary ammonium salt may be either chain or cyclic. Further, the number of nitrogen atoms constituting the amine moiety or ammonium salt moiety (for example, the nitrogen atom constituting the amino group (—NH ₂ ) of the primary amine) may be one, or two or more.

Examples of the primary amine include monoalkylamines, monoarylamines, mono (heteroaryl) amines, and diamines in which one or more hydrogen atoms may be substituted with a substituent.

The alkyl group constituting the monoalkylamine may be linear, branched or cyclic, and examples thereof are the same as the alkyl group in R, and are linear or branched having 1 to 19 carbon atoms. It is preferably a chain alkyl group or a cyclic alkyl group having 3 to 7 carbon atoms.
Specific examples of preferable monoalkylamine include n-butylamine, n-hexylamine, n-octylamine, n-dodecylamine, n-octadecylamine, sec-butylamine, tert-butylamine, isobutylamine, and 3-amino. Examples include pentane, 3-methylbutylamine, 2-heptylamine (2-aminoheptane), 2-aminooctane, 2-ethylhexylamine, and 1,2-dimethyl-n-propylamine.

Examples of the aryl group constituting the monoarylamine include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, and the like, and preferably has 6 to 10 carbon atoms.

The heteroaryl group constituting the mono (heteroaryl) amine has a heteroatom as an atom constituting the aromatic ring skeleton, and the heteroatom includes a nitrogen atom, a sulfur atom, an oxygen atom, and a boron atom. Can be illustrated. Moreover, the number of the said hetero atom which comprises an aromatic ring frame is not specifically limited, One may be sufficient and two or more may be sufficient. When there are two or more, these heteroatoms may be the same or different from each other. That is, these heteroatoms may all be the same, may all be different, or may be partially different.
The heteroaryl group may be either monocyclic or polycyclic, and the number of ring members (the number of atoms constituting the ring skeleton) is not particularly limited, but is preferably a 3- to 12-membered ring.

Examples of the monoaryl group having 1 to 4 nitrogen atoms as the heteroaryl group include pyrrolyl group, pyrrolinyl group, imidazolyl group, pyrazolyl group, pyridyl group, pyrimidyl group, pyrazinyl group, pyridazinyl group, triazolyl group, tetrazolyl group A pyrrolidinyl group, an imidazolidinyl group, a piperidinyl group, a pyrazolidinyl group, and a piperazinyl group, which are preferably 3- to 8-membered rings, and more preferably 5- to 6-membered rings.
Examples of the monoaryl group having one oxygen atom as the heteroaryl group include a furanyl group, preferably a 3- to 8-membered ring, and more preferably a 5- to 6-membered ring.
Examples of the monoaryl group having one sulfur atom as the heteroaryl group include a thienyl group, preferably a 3- to 8-membered ring, and more preferably a 5- to 6-membered ring.
Examples of the monoaryl group having 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms as the heteroaryl group include an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, and a morpholinyl group. Preferably, it is a 5- to 6-membered ring.
Examples of the monoaryl group having 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms as the heteroaryl group include a thiazolyl group, a thiadiazolyl group, and a thiazolidinyl group, and is a 3- to 8-membered ring. A 5- to 6-membered ring is preferable.
Examples of the polyaryl having 1 to 5 nitrogen atoms as the heteroaryl group include indolyl group, isoindolyl group, indolizinyl group, benzimidazolyl group, quinolyl group, isoquinolyl group, indazolyl group, benzotriazolyl group, tetra Examples thereof include a zolopyridyl group, a tetrazolopyridazinyl group, and a dihydrotriazolopyridazinyl group, preferably a 7-12 membered ring, and more preferably a 9-10 membered ring.
Examples of the polyaryl group having 1 to 3 sulfur atoms as the heteroaryl group include a dithiaphthalenyl group and a benzothiophenyl group, preferably a 7 to 12 membered ring, preferably a 9 to 10 membered ring. More preferably, it is a ring.
Examples of the polyaryl group having 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms as the heteroaryl group include a benzoxazolyl group and a benzooxadiazolyl group. Preferably, it is a 9 to 10 membered ring.
Examples of the polyaryl group having 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms as the heteroaryl group include a benzothiazolyl group and a benzothiadiazolyl group, and is a 7 to 12 membered ring. Preferably, it is a 9 to 10 membered ring.

The diamine only needs to have two amino groups, and the positional relationship between the two amino groups is not particularly limited. As the preferred diamine, in the monoalkylamine, monoarylamine or mono (heteroaryl) amine, one hydrogen atom other than the hydrogen atom constituting the amino group (—NH ₂ ) is substituted with an amino group. The thing can be illustrated.
The diamine preferably has 1 to 10 carbon atoms, and more preferable examples include ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane.

Examples of the secondary amine include dialkylamine, diarylamine, di (heteroaryl) amine and the like in which one or more hydrogen atoms may be substituted with a substituent.

The alkyl group constituting the dialkylamine is the same as the alkyl group constituting the monoalkylamine, and is a linear or branched alkyl group having 1 to 9 carbon atoms, or having 3 to 7 carbon atoms. A cyclic alkyl group is preferred. Two alkyl groups in one molecule of dialkylamine may be the same as or different from each other.
Specific examples of preferable dialkylamines include N-methyl-n-hexylamine, diisobutylamine, and di (2-ethylhexyl) amine.

The aryl group constituting the diarylamine is the same as the aryl group constituting the monoarylamine, and preferably has 6 to 10 carbon atoms. Two aryl groups in one molecule of diarylamine may be the same as or different from each other.

The heteroaryl group constituting the di (heteroaryl) amine is the same as the heteroaryl group constituting the mono (heteroaryl) amine, and is preferably a 6-12 membered ring. Two heteroaryl groups in one molecule of di (heteroaryl) amine may be the same or different from each other.

Examples of the tertiary amine include trialkylamine and dialkylmonoarylamine in which one or more hydrogen atoms may be substituted with a substituent.

The alkyl group constituting the trialkylamine is the same as the alkyl group constituting the monoalkylamine, and is a linear or branched alkyl group having 1 to 19 carbon atoms, or 3 to 7 carbon atoms. The cyclic alkyl group is preferably. Further, the three alkyl groups in one molecule of trialkylamine may be the same as or different from each other. That is, all three alkyl groups may be the same, all may be different, or only a part may be different.
Preferable examples of the trialkylamine include N, N-dimethyl-n-octadecylamine and N, N-dimethylcyclohexylamine.

The alkyl group constituting the dialkyl monoarylamine is the same as the alkyl group constituting the monoalkylamine, and is a linear or branched alkyl group having 1 to 6 carbon atoms, or 3 to 3 carbon atoms. 7 is a cyclic alkyl group. Two alkyl groups in one molecule of dialkyl monoarylamine may be the same or different from each other.
The aryl group constituting the dialkyl monoarylamine is the same as the aryl group constituting the monoarylamine, and preferably has 6 to 10 carbon atoms.

In the present invention, examples of the quaternary ammonium salt include halogenated tetraalkylammonium, in which one or more hydrogen atoms may be substituted with a substituent.
The alkyl group constituting the halogenated tetraalkylammonium is the same as the alkyl group constituting the monoalkylamine, and preferably has 1 to 19 carbon atoms.
Further, the four alkyl groups in one molecule of the tetraalkylammonium halide may be the same as or different from each other. That is, all four alkyl groups may be the same, all may be different, or only a part may be different.
Examples of the halogen constituting the halogenated tetraalkylammonium include fluorine, chlorine, bromine and iodine.
Specific examples of the preferred tetraalkylammonium halide include dodecyltrimethylammonium bromide.

So far, the chain amine compound and the quaternary organic ammonium salt have been mainly described. However, in the amine compound and the quaternary ammonium salt, the nitrogen atom constituting the amine moiety or the ammonium salt moiety is a ring skeleton structure ( A heterocyclic compound which is a part of a heterocyclic skeleton structure) may be used. That is, the amine compound may be a cyclic amine, and the quaternary ammonium salt may be a cyclic ammonium salt. At this time, the ring (ring containing the nitrogen atom constituting the amine moiety or ammonium salt moiety) structure may be either monocyclic or polycyclic, and the number of ring members (number of atoms constituting the ring skeleton) is also particularly limited. Any of an aliphatic ring and an aromatic ring may be sufficient.
If it is a cyclic amine, a pyridine can be illustrated as a preferable thing.

In the primary amine, secondary amine, tertiary amine and quaternary ammonium salt, the “hydrogen atom optionally substituted with a substituent” means a nitrogen atom constituting an amine moiety or an ammonium salt moiety. A hydrogen atom other than a hydrogen atom bonded to. The number of substituents at this time is not particularly limited, and may be one or two or more, and all of the hydrogen atoms may be substituted with a substituent. When the number of substituents is plural, the plural substituents may be the same as or different from each other. That is, the plurality of substituents may all be the same, may all be different, or only some may be different. Further, the position of the substituent is not particularly limited.

Examples of the substituent in the amine compound and the quaternary ammonium salt include an alkyl group, an aryl group, a halogen atom, a cyano group, a nitro group, a hydroxyl group, and a trifluoromethyl group (—CF ₃ ). Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

When the alkyl group constituting the monoalkylamine has a substituent, the alkyl group has an aryl group as a substituent, a linear or branched alkyl group having 1 to 9 carbon atoms, or a substituent Preferably, a cyclic alkyl group having 3 to 7 carbon atoms having an alkyl group having 1 to 5 carbon atoms is preferable, and a monoalkylamine having such a substituent is specifically 2-phenylethylamine. , Benzylamine, and 2,3-dimethylcyclohexylamine.
In addition, the aryl group and the alkyl group which are substituents may further have one or more hydrogen atoms substituted with halogen atoms, and as monoalkylamines having such substituents substituted with halogen atoms, And 2-bromobenzylamine. Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

When the aryl group constituting the monoarylamine has a substituent, the aryl group is preferably an aryl group having 6 to 10 carbon atoms having a halogen atom as the substituent, and the monoaryl having such a substituent Specific examples of the amine include bromophenylamine. Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

When the alkyl group constituting the dialkylamine has a substituent, the alkyl group is preferably a linear or branched alkyl group having 1 to 9 carbon atoms and having a hydroxyl group or an aryl group as a substituent. Specific examples of the dialkylamine having such a substituent include diethanolamine and N-methylbenzylamine.

The amine compound includes n-propylamine, n-butylamine, n-hexylamine, n-octylamine, n-dodecylamine, n-octadecylamine, sec-butylamine, tert-butylamine, isobutylamine, 3-aminopentane, 3-methylbutylamine, 2-heptylamine, 2-aminooctane, 2-ethylhexylamine, 2-phenylethylamine, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, N-methyl-n-hexylamine, Diisobutylamine, N-methylbenzylamine, di (2-ethylhexyl) amine, 1,2-dimethyl-n-propylamine, N, N-dimethyl-n-octadecylamine or N, N-dimethylcyclohexylamine It is preferable.
Among these amine compounds, 2-ethylhexylamine is excellent in compatibility with the above-mentioned silver carboxylate, particularly suitable for increasing the concentration of the silver ink composition, and particularly for reducing the surface roughness of silver fine wires. Listed as suitable.

(Ammonium salts derived from amine compounds)
In the present invention, the ammonium salt derived from the amine compound is an ammonium salt obtained by reacting the amine compound with an acid, and the acid may be an inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid, or an organic acid such as acetic acid. However, the type of acid is not particularly limited.
Examples of the ammonium salt derived from the amine compound include, but are not limited to, n-propylamine hydrochloride, N-methyl-n-hexylamine hydrochloride, N, N-dimethyl-n-octadecylamine hydrochloride and the like. .

(Ammonium salt derived from ammonia)
In the present invention, the ammonium salt derived from ammonia is an ammonium salt obtained by reacting ammonia with an acid, and examples of the acid include the same ones as in the case of the ammonium salt derived from the amine compound.
Examples of the ammonium salt derived from ammonia include ammonium chloride, but are not limited thereto.

In the present invention, the amine compound, the quaternary ammonium salt, the ammonium salt derived from the amine compound and the ammonium salt derived from ammonia may be used singly or in combination of two or more. . When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.
And as said nitrogen-containing compound, you may use individually by 1 type selected from the group which consists of said amine compound, quaternary ammonium salt, ammonium salt derived from an amine compound, and ammonium salt derived from ammonia, More than one species may be used in combination. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.

In the silver ink composition, the compounding amount of the nitrogen-containing compound is preferably 0.3 to 15 mol, more preferably 0.3 to 5 mol, per mol of the metal silver forming material. preferable. When the blending amount of the nitrogen-containing compound is within such a range, the silver ink composition is further improved in stability and the quality of the conductor (metal silver) is further improved. Furthermore, the conductor can be formed more stably without performing heat treatment at a high temperature.

[Reducing compounds]
In addition to the metallic silver forming material, the silver ink composition further contains a reducing compound, so that the silver ink composition can form metallic silver more easily. For example, heat treatment at a low temperature is sufficient. It is possible to form a conductive material (metallic silver) having excellent conductivity.

The reducing compound is one or more selected from the group consisting of oxalic acid (HOOC-COOH), hydrazine (H ₂ N—NH ₂ ), and a compound represented by the following general formula (5) (compound (5)). It is. That is, the reducing compound to be blended may be one kind or two or more kinds. When two or more kinds are used in combination, the combination and ratio can be arbitrarily adjusted.
HC (= O) -R ²¹ (5)
(Wherein R ²¹ represents an alkyl group having 20 or less carbon atoms, an alkoxy group, or an N, N-dialkylamino group, a hydroxyl group, or an amino group.)

The alkyl group having 20 or less carbon atoms in R ²¹ has 1 to 20 carbon atoms and may be linear, branched or cyclic, and is the same as the alkyl group in R in the general formula (1) The thing can be illustrated.

The alkoxy group having 20 or less carbon atoms in R ²¹ has 1 to 20 carbon atoms, and examples thereof include monovalent groups in which the alkyl group in R ²¹ is bonded to an oxygen atom.

The N, N-dialkylamino group having 20 or less carbon atoms in R ²¹ has 2 to 20 carbon atoms, and the two alkyl groups bonded to the nitrogen atom may be the same as or different from each other. Each alkyl group has 1 to 19 carbon atoms. However, the total value of the carbon number of these two alkyl groups is 2 to 20.
The alkyl group bonded to the nitrogen atom may be linear, branched or cyclic, respectively, and the alkyl group in R of the general formula (1) except that it has 1 to 19 carbon atoms. The thing similar to group can be illustrated.

As the reducing compound, hydrazine may be monohydrate (H ₂ N—NH ₂ .H ₂ O).

Preferred examples of the reducing compound include formic acid (HC (═O) —OH); methyl formate (HC (═O) —OCH ₃ ), ethyl formate (HC (═O) —OCH). ₂ CH ₃ ), formic acid esters such as butyl formate (HC (═O) —O (CH ₂ ) ₃ CH ₃ ); propanal (HC (═O) —CH ₂ CH ₃ ), butanal (H _{-C (= O) - (CH} 2) 2 CH 3), hexanal (H-C (= O) - (CH 2) 4 aldehyde CH ₃₎ or the like; dimethylformamide (H-C (= O) -NH 2 ), N, N-dimethylformamide (HC (═O) —N (CH ₃ ) ₂ ) and other formamides (groups represented by the formula “HC (═O) —N (—) —”) And oxalic acid.

In the silver ink composition, the compounding amount of the reducing agent is preferably 0.04 to 3.5 mol, and preferably 0.06 to 2.5 mol per mol of the metal silver forming material. Is more preferable. When the blending amount of the reducing agent is within such a range, the silver ink composition can form a conductor (metal silver) more easily and more stably.

[alcohol]
The alcohol is preferably an acetylene alcohol represented by the following general formula (2) (hereinafter sometimes abbreviated as “acetylene alcohol (2)”).

(In the formula, R ′ and R ″ are each independently an alkyl group having 1 to 20 carbon atoms, or a phenyl group in which one or more hydrogen atoms may be substituted with a substituent.)

(Acetylene alcohol (2))
The acetylene alcohol (2) is represented by the general formula (2).
In the formula, R ′ and R ″ are each independently an alkyl group having 1 to 20 carbon atoms or a phenyl group in which one or more hydrogen atoms may be substituted with a substituent.
The alkyl group having 1 to 20 carbon atoms in R ′ and R ″ may be linear, branched or cyclic, and when it is cyclic, it may be monocyclic or polycyclic. Examples of the alkyl group in R ′ and R ″ include the same alkyl groups as in R.

Examples of the substituent in which the hydrogen atom of the phenyl group in R ′ and R ″ may be substituted include a saturated or unsaturated monovalent aliphatic hydrocarbon group having 1 to 16 carbon atoms, the aliphatic carbon Examples thereof include a monovalent group formed by bonding a hydrogen group to an oxygen atom, a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, a cyano group, a phenoxy group, and the like, and the hydrogen atom of the phenyl group in R may be substituted. This is the same as the substituent. And the number and position of a substituent are not specifically limited, When there are two or more substituents, these several substituents may mutually be same or different.

R ′ and R ″ are preferably an alkyl group having 1 to 20 carbon atoms, and more preferably a linear or branched alkyl group having 1 to 10 carbon atoms.

Examples of preferable acetylene alcohol (2) include 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-butyn-3-ol, and 3-methyl-1-pentyn-3-ol.

When acetylene alcohol (2) is used, the amount of acetylene alcohol (2) in the silver ink composition is preferably 0.03 to 0.7 mol per mol of the metal silver forming material. 0.05 to 0.3 mol is more preferable. When the blending amount of acetylene alcohol (2) is within such a range, the stability of the silver ink composition is further improved.

The alcohol may be used alone or in combination of two or more. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.

[Other ingredients]
The silver ink composition may contain other components other than the metallic silver forming material, nitrogen-containing compound, reducing agent, and alcohol.
The other components in the silver ink composition can be arbitrarily selected according to the purpose, and are not particularly limited. Preferred examples thereof include solvents other than alcohol, and can be arbitrarily selected according to the type and amount of compounding components. it can.
One of these other components in the silver ink composition may be used alone, or two or more thereof may be used in combination. When using 2 or more types together, the combination and ratio can be adjusted arbitrarily.

In the silver ink composition, the ratio of the blending amount of the other components to the total blending component is preferably 10% by mass or less, more preferably 5% by mass or less, and 0% by mass, ie, other Even if the component is not blended, the silver ink composition exhibits its effect sufficiently.

In the silver ink composition, all the compounding components may be dissolved, or some or all of the components may be dispersed without dissolving, but it is preferable that all the compounding components are dissolved. The undissolved component is preferably dispersed uniformly.

[Method for producing silver ink composition]
The silver ink composition can be obtained, for example, by blending one or both of silver carboxylate, nitrogen-containing compound, reducing compound and alcohol, and other components as required. After the blending of each component, the resulting product may be used as it is as a silver ink composition, or a product obtained by performing a known purification operation as necessary may be used as a silver ink composition. In the present invention, at the time of blending each of the above components, impurities that inhibit conductivity are not generated, or the amount of such impurities generated can be suppressed to an extremely small amount, so that it is not necessary to perform a purification operation. A metallic silver layer having excellent conductivity can be obtained.

At the time of blending each component, all the components may be added and then mixed, or some components may be mixed while being added sequentially, or all components may be mixed while being added sequentially. Good.

The mixing method is not particularly limited, a method of mixing by rotating a stirrer or a stirring blade; a method of mixing using a mixer, a three-roller, a kneader, a bead mill or the like; a method of mixing by adding ultrasonic waves, etc. What is necessary is just to select suitably from a well-known method.

In particular, a method of rotating and mixing the stirring blade in the stirring vessel is preferable, and the stirring blade is preferably in an anchor shape. When stirring with an anchor-shaped stirring blade, stirring efficiency is high, and it is considered that the material of the silver ink composition can be reacted efficiently.

Examples of the anchor-shaped stirring blade include a stirring blade 100 shown in FIG. 1. FIG. 1 is a schematic diagram showing an anchor-shaped stirring blade 100. The stirring blade 100 includes a drive shaft 110, a forced flow generating blade portion 120 having an outer side 120a that rotates in the vicinity of the inner peripheral surface of the stirring tank (beaker), the drive shaft 110, and the forced flow generating blade portion 120. And a connecting portion 130 for connecting the two.
The forced flow generating blade part 120 preferably extends in the depth direction of the stirring tank (in a direction parallel to the drive shaft 110). In this case, the forced flow generating blade portion 120 may extend linearly in parallel with the drive shaft 110 as shown in FIG. Or the forced flow generation | occurrence | production blade | wing part 120 may be extended in the depth direction of a stirring tank, for example, twisting helically.
The diameter of the stirring blade (the distance from one outer side 120a to the other outer periphery 120a in FIG. 1) with respect to the inner diameter (diameter) of the stirring tank is preferably 85 to 95%.

Examples of the anchor-shaped stirring blade include a stirring blade 300 shown in FIG. 3. FIG. 3 is a schematic view showing another stirring blade 300 having an anchor shape.
A stirring blade 300 shown in FIG. 3 is a Max Blend type, and includes a drive shaft 310, a forced flow generation blade portion 320 having an outer side 320a that rotates around the inner peripheral surface of a stirring tank (beaker), and the drive. A first connecting part 330 connecting the shaft 310 and the forced flow generating blade part 320 at the lower part thereof, and a second connecting part 340 connecting the drive shaft 310 and the forced flow generating blade part 320 at the upper part thereof. And. Further, the stirring blade 300 includes a third connection portion 350 that connects the first connection portion 330 and the second connection portion 340 at a position between the drive shaft 310 and the forced flow generation blade portion 320. ing.
The agitating blade 300 shown in FIG. 3 includes the first connecting portion 330 and the second connecting portion 340 for connecting the drive shaft 310 and the forced flow generating blade portion 320, and further connecting the connecting portions to each other. Except for the point provided with the 3rd connection part 350 connected, it is the same as that of the stirring blade 100 shown in FIG.

The widths of the first connection part 330 and the second connection part 340 are not particularly limited. For example, as illustrated in FIG. 3, the first connection part 330 may be wider than the second connection part 340. Alternatively, the second connecting part 340 may be wider than the first connecting part 330, and the first connecting part 330 and the second connecting part 340 may have the same width.
The same applies to the widths of the forced flow generating blade portion 320 and the third connecting portion 350. For example, the forced flow generating blade portion 320 may be wider than the third connecting portion 350 as shown in FIG. Alternatively, the third connecting part 350 may be wider than the forced flow generating blade part 320, and the forced flow generating blade part 320 and the third connecting part 350 may have the same width.

In the present invention, the silver ink composition is prepared by rotating a stirring blade in a stirring tank of the silver carboxylate, the nitrogen-containing compound, and the reducing compound and / or a mixture (formulation) of alcohol. What was manufactured by the manufacturing method including the process of stirring is preferable.

The rotation speed when mixing the components of the silver ink composition by rotating the anchor-shaped stirring blade is, for example, 100 to 500 rpm when the total of the materials of the silver ink composition is about 30 to 300 g. preferable.

In the silver ink composition, all of the compounding components may be dissolved, or a part of the components may be dispersed without dissolving, but it is preferable that all of the compounding components are dissolved, It is preferable that the components which are not dissolved are uniformly dispersed. In the case of uniformly dispersing the undissolved component, for example, it is preferable to apply a method of dispersing using the above-described three-roll, kneader or bead mill.

The temperature at the time of compounding is not particularly limited as long as each compounding component does not deteriorate, but it is preferably −5 to 60 ° C. And the temperature at the time of mixing | blending is good to adjust suitably so that the mixture obtained by mix | blending may become the viscosity which is easy to stir according to the kind and quantity of a mixing | blending component.
Further, the blending time is not particularly limited as long as each blending component is not deteriorated, but is, for example, 10 minutes to 36 hours, for example, 0.5 to 12 hours.

For example, when the silver carboxylate and the reducing compound are mixed together, the resulting mixture (silver ink composition) is relatively easy to generate heat. And, when the temperature at the time of blending these is high, this mixture will be in the same state as at the time of heat treatment of the silver ink composition to be described later, so by the decomposition promoting action of the silver carboxylate by the reducing compound, It is speculated that the formation of metallic silver may be initiated in at least part of the silver carboxylate. Such a silver ink composition containing metallic silver can form a metallic silver layer by performing post-treatment under milder conditions than a silver ink composition not containing metallic silver during the production of the laminate. is there. Moreover, even when the compounding amount of the reducing compound is sufficiently large, a metallic silver layer may be formed by performing post-treatment under the same mild conditions. Thus, by adopting conditions that promote the decomposition of the silver carboxylate, as a post-treatment, the metal silver layer can be obtained by a heat treatment at a lower temperature or only by a drying treatment at room temperature without performing the heat treatment. Can be formed. Moreover, the silver ink composition containing such metal silver can be handled in the same manner as the silver ink composition not containing metal silver, and the handleability is not particularly inferior.

In the present invention, for example, after the silver carboxylate and the nitrogen-containing compound are blended, the reducing compound is blended to produce the silver ink composition, the dripping of the reducing compound is blended. Preferably, the surface roughness of the metallic silver layer tends to be further reduced by suppressing fluctuations in the dropping speed.

[carbon dioxide]
The silver ink composition may be further supplied with carbon dioxide. Such a silver ink composition has a high viscosity. For example, a flexographic printing method, a screen printing method, a gravure printing method, a gravure offset printing method, a pad printing method, etc. Suitable for application.

Carbon dioxide may be supplied at any time during the production of the silver ink composition.
For example, a silver ink composition is obtained by supplying carbon dioxide to a first mixture in which silver carboxylate and a nitrogen-containing compound are blended to form a second mixture, and further blending a reducing compound in the second mixture. You may manufacture things. Moreover, when mix | blending the said alcohol or another component, these can be mix | blended at the time of manufacture of any one or both of a 1st mixture and a 2nd mixture, and can be arbitrarily selected according to the objective.

The first mixture can be produced by the same method as the above silver ink composition except that the blending components are different.

The first mixture may have all of the compounding components dissolved, or may be in a state of being dispersed without dissolving some of the components, but preferably all of the compounding components are dissolved and dissolved. It is preferable that the components not dispersed are uniformly dispersed.

The compounding temperature at the time of producing the first mixture is not particularly limited as long as each compounding component does not deteriorate, but it is preferably −5 to 60 ° C. The blending time may be appropriately adjusted according to the type of blending component and the temperature at the blending, and is, for example, 10 minutes to 36 hours, for example 0.5 to 12 hours.

Carbon dioxide (CO ₂ ) supplied to the first mixture may be either gaseous or solid (dry ice), or both gaseous and solid. By supplying carbon dioxide, it is estimated that this carbon dioxide dissolves in the first mixture and acts on the components in the first mixture, thereby increasing the viscosity of the obtained second mixture.

The carbon dioxide gas may be supplied by various known methods for blowing gas into the liquid, and a suitable supply method may be selected as appropriate. For example, a method in which one end of a pipe is immersed in the first mixture, the other end is connected to a carbon dioxide gas supply source, and the carbon dioxide gas is supplied to the first mixture through the pipe. At this time, the carbon dioxide gas may be supplied directly from the end of the pipe. For example, a plurality of voids that can serve as gas flow paths, such as a porous one, are provided to diffuse the introduced gas. A gas diffusion member that can be discharged as minute bubbles may be connected to the end of the pipe, and the carbon dioxide gas may be supplied through the gas diffusion member. Moreover, you may supply a carbon dioxide gas, stirring the 1st mixture by the method similar to the time of manufacture of a 1st mixture. By doing in this way, carbon dioxide can be supplied efficiently.

The supply amount of carbon dioxide gas is not particularly limited, and may be appropriately adjusted according to the amount of the first mixture at the supply destination and the viscosity of the target silver ink composition or the second mixture. For example, in order to obtain about 100 to 1000 g of a silver ink composition having a viscosity of 5 Pa · s or more measured at 20 to 25 ° C. with an ultrasonic viscometer (“VISCOMATE VM-10A” manufactured by CBC), It is preferable to supply 100 L or more of carbon gas, and it is more preferable to supply 200 L or more. Although the viscosity at 20 to 25 ° C. of the silver ink composition has been described here, the temperature at the time of using the silver ink composition is not limited to 20 to 25 ° C. and can be arbitrarily selected.

The flow rate of carbon dioxide gas may be appropriately adjusted in consideration of the required supply amount of carbon dioxide gas, but is preferably 0.5 mL / min or more per 1 g of the first mixture, and is 1 mL / min or more. It is more preferable that The upper limit value of the flow rate is not particularly limited, but is preferably 40 mL / min per 1 g of the mixture in consideration of handling properties and the like.
The carbon dioxide gas supply time may be appropriately adjusted in consideration of the required supply amount and flow rate of carbon dioxide gas.

The temperature of the first mixture at the time of supplying carbon dioxide gas is preferably 5 to 70 ° C, more preferably 7 to 60 ° C, and particularly preferably 10 to 50 ° C. When the temperature is equal to or higher than the lower limit value, carbon dioxide can be supplied more efficiently, and when the temperature is equal to or lower than the upper limit value, a silver ink composition having better quality with fewer impurities can be obtained.

The flow rate and supply time of carbon dioxide gas, and the temperature at the time of supplying carbon dioxide gas may be adjusted to a suitable range while considering each value. For example, even if the temperature is set lower, the carbon dioxide gas flow rate is set higher, the carbon dioxide gas supply time is set longer, or both are performed efficiently. Can supply carbon. Moreover, even if the flow rate of carbon dioxide gas is set to a small value, the carbon dioxide gas can be efficiently produced by increasing the temperature, setting the carbon dioxide gas supply time longer, or both. Can supply. That is, a silver ink of good quality can be obtained by flexibly combining the numerical values in the above numerical range exemplified as the flow rate of carbon dioxide gas and the temperature at the time of carbon dioxide gas supply while considering the supply time of carbon dioxide gas. A composition is obtained efficiently.

The carbon dioxide gas is preferably supplied while stirring the first mixture. By doing in this way, the supplied carbon dioxide gas diffuses more uniformly in the first mixture, and carbon dioxide can be supplied more efficiently.
The stirring method at this time may be the same as in the case of the mixing method at the time of producing the above silver ink composition not using carbon dioxide.

The supply of dry ice (solid carbon dioxide) may be performed by adding dry ice to the first mixture. The total amount of dry ice may be added all at once, or may be added stepwise (continuously across a time zone during which no addition is performed).
What is necessary is just to adjust the usage-amount of dry ice in consideration of the supply amount of said carbon dioxide gas.
During and after the addition of dry ice, the first mixture is preferably stirred. For example, the first mixture is preferably stirred in the same manner as in the production of the above silver ink composition without using carbon dioxide. By doing in this way, carbon dioxide can be supplied efficiently.
The temperature at the time of stirring may be the same as that at the time of supplying carbon dioxide gas. Moreover, what is necessary is just to adjust stirring time suitably according to stirring temperature.

The viscosity of the second mixture may be appropriately adjusted according to the purpose, such as a method for handling the silver ink composition or the second mixture, and is not particularly limited. For example, when the silver ink composition is applied to a printing method using a high viscosity ink such as a screen printing method or a flexographic printing method, the viscosity of the second mixture at 20 to 25 ° C. is 3 Pa · s or more. It is preferable. Here, the viscosity of the second mixture at 20 to 25 ° C. has been described, but the temperature at the time of use of the second mixture is not limited to 20 to 25 ° C. and can be arbitrarily selected.

A reductive compound is mix | blended with said 2nd mixture, Furthermore, 1 or more types selected from the group which consists of alcohol and another component can be mix | blended as needed, and it can be set as a silver ink composition.
The silver ink composition at this time can be manufactured by the same method as the above silver ink composition not using carbon dioxide except that the blending components are different. The obtained silver ink composition may have all of the compounding components dissolved therein or may be in a state where some of the components are dispersed without dissolving, but all of the compounding components are dissolved. Preferably, the undissolved component is preferably dispersed uniformly.

The temperature at the time of compounding the reducing compound is not particularly limited as long as each compounding component does not deteriorate, but it is preferably −5 to 60 ° C. And the temperature at the time of mixing | blending is good to adjust suitably so that the mixture obtained by mix | blending may become the viscosity which is easy to stir according to the kind and quantity of a mixing | blending component.
The blending time may be appropriately adjusted according to the type of blending component and the temperature at the blending, and is, for example, 10 minutes to 36 hours, for example 0.5 to 12 hours.

As described above, the other components may be blended during the production of either the first mixture or the second mixture, or may be blended during the production of both. That is, in the process of producing the silver ink composition through the first mixture and the second mixture, the ratio of the blended amount of the other components to the total amount of blended components other than carbon dioxide ([other components (mass)] / [Silver carboxylate, nitrogen-containing compound, reducing compound, alcohol, and other components (mass)] × 100) is preferably 10% by mass or less, more preferably 5% by mass or less, Even if 0% by mass, that is, no other components are blended, the silver ink composition exhibits its effect sufficiently.

The silver ink composition to which carbon dioxide is supplied is, for example, a viscosity at 20 to 25 ° C. when the silver ink composition is applied to a printing method using a high viscosity ink such as a screen printing method or a flexographic printing method. Is preferably 1 Pa · s or more.

Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

[Examples 1 to 3]
(Preparation of silver ink composition)
Silver 2-methylacetoacetate (38.0 g) was added to 2-ethylhexylamine (22.0 g) in a 200 mL beaker so that the liquid temperature was 50 ° C. or lower, and the mixture was stirred for 15 minutes using a mechanical stirrer. As a result, a liquid material was obtained.

The anchor stirrer was used for the stirring blade of the mechanical stirrer. FIG. 1 is a schematic diagram showing an anchor-shaped stirring blade 100. The stirring blade 100 includes a drive shaft 110, a forced flow generating blade portion 120 having an outer side 120a that rotates in the vicinity of the inner peripheral surface of the stirring tank (beaker), the drive shaft 110, and the forced flow generating blade portion 120. And a connecting portion 130 for connecting the two. The stirring blade 100 had a stirring blade diameter of about 95% with respect to the inner diameter (diameter) of the beaker, and the distance between the inner peripheral surface of the beaker and the outer side 120a of the forced flow generation blade portion 120 was about 2 mm. . Moreover, the rotation speed of the stirring blade 100 was set to 300 rpm.

Formic acid (6.3 g) was added dropwise to the above-mentioned liquid over 30 minutes so that the temperature of the reaction solution was 50 ° C. or lower. After the formic acid was dropped, the reaction solution was further stirred at 25 ° C. for 1.5 hours to obtain a silver ink composition. The blending amounts of 2-ethylhexylamine and formic acid per 1 mole of silver 2-methylacetoacetate were 1 mole and 0.8 mole, respectively.

(Production of laminate)
Using the obtained silver ink composition, screen printing was performed on a polyethylene terephthalate (PET) film (“Lumirror S10” manufactured by Toray Industries, Inc., 100 μm thick) as a base material. As the screen plate, a 500-mesh stainless steel plate was used, and a pattern with a line width of 0.5 mm and a line length of 30 mm was printed under the condition of an emulsion thickness of 10 μm.

Next, the obtained printed pattern was baked (heat treatment) at 80 ° C. for 1 hour to form a metal silver layer, whereby the laminate of Example 1 was obtained. In the same manner as in Example 1, the production of the silver ink composition and the laminate was repeated, and the laminates of Examples 2 and 3 were obtained.

[Comparative Examples 1 to 3]
(Preparation of silver ink composition)
By adding silver 2-methylacetoacetate (38.0 g) to 2-ethylhexylamine (22.0 g) in a beaker so that the liquid temperature is 50 ° C. or lower, and stirring for 15 minutes using a mechanical stirrer. A liquid product was obtained.

The propeller-shaped one was used for the stirring blade of the mechanical stirrer. FIG. 2 is a schematic diagram showing a propeller-shaped stirring blade 200. The stirring blade 200 includes a drive shaft 210 and a propeller-like forced flow generation blade portion 220. The rotation speed of the stirring blade was set to 300 rpm.

Formic acid (6.3 g) was added dropwise to the above-mentioned liquid over 30 minutes so that the temperature of the reaction solution was 50 ° C. or lower. After the formic acid was dropped, the reaction solution was further stirred at 25 ° C. for 1.5 hours to obtain a silver ink composition. The blending amounts of 2-ethylhexylamine and formic acid per 1 mole of silver 2-methylacetoacetate were 1 mole and 0.8 mole, respectively.

(Production of laminate)
Using the obtained silver ink composition, screen printing was performed on a polyethylene terephthalate (PET) film (“Lumirror S10” manufactured by Toray Industries, Inc., 100 μm thick) as a base material. As the screen plate, a 500-mesh stainless steel plate was used, and a pattern with a line width of 0.5 mm and a line length of 30 mm was printed under the condition of an emulsion thickness of 10 μm.

Next, the obtained printed pattern was baked (heat treatment) at 80 ° C. for 1 hour to form a metallic silver layer, whereby a laminate of Comparative Example 1 was obtained. In the same manner as in Comparative Example 1, the production of the silver ink composition and the laminate was repeated, and the laminates of Comparative Examples 2 and 3 were obtained.

[Evaluation of silver ink composition]
(Stirring state)
In Examples 1 to 3 and Comparative Examples 1 to 3, the stirring state when the materials of the silver ink composition were stirred with a mechanical stirrer was visually evaluated. The results are shown in Table 1 below. “○” when the material is evenly stirred and there is little or no material adhering to the wall surface of the stirring vessel, and when the material is partly unevenly stirred and relatively much material adhering to the wall surface of the stirring vessel. The case where “Δ” was not stirred at all was evaluated as “x”.

(Weight reduction rate)
In Examples 1 to 3 and Comparative Examples 1 to 3, the mass of the completed silver ink composition was quantified. Further, the ratio of the mass of the completed silver ink composition to the total mass of 2-ethylhexylamine, silver 2-methylacetoacetate and formic acid used as the material of the silver ink composition was calculated, and the weight reduction rate was calculated by the following formula. (Mass%) was calculated. The results are shown in Table 1 below. The larger the weight reduction rate, the more the reaction of the material progresses, indicating that it has been lost as a volatile component.
Weight reduction rate (mass%) = 1- (mass of silver ink composition) / (total mass of 2-ethylhexylamine, silver 2-methylacetoacetate and formic acid)

(Silver concentration)
In Examples 1 to 3 and Comparative Examples 1 to 3, the silver ink composition was quantified and placed in a crucible and heat treated at 400 ° C. for 3 hours. The metallic silver remaining in the crucible after the heat treatment was quantified, and the silver concentration in the ink composition (% by mass) was calculated. The results are shown in Table 1 below. It shows that there are few impurities, so that silver concentration is high.

(viscosity)
In Examples 1 to 3 and Comparative Examples 1 to 3, using a rheometer (“MCR-301” manufactured by Anton Paar), the viscosity of the silver ink composition at a shear rate of 10 s ⁻¹ under an environment of 25 ° C. Was measured. CP-25-2 (diameter 25 mm, cone angle 2 °) was used as the cone plate.

(Color)
In Examples 1 to 3 and Comparative Examples 1 to 3, the color of the silver ink composition was judged visually. The results are shown in Table 1 below.

[Evaluation of produced laminate]
For the metallic silver layers of the laminates of Examples 1 to 3 and Comparative Examples 1 to 3, the line resistance value R (Ω), the cross-sectional area A (cm ² ), and the line length L (cm) were measured, and the formula “ρ = R × A / L ”, the volume resistivity ρ (Ω · cm) was calculated. The line resistance value R was measured using a digital multimeter (“PC5000a” manufactured by Sanwa Denki Keiki Co., Ltd.), and the cross-sectional area A was measured using a shape measurement laser microscope (“VK-X100” manufactured by Keyence Corporation). did. Further, the surface roughness (arithmetic average surface roughness Ra) of the formed pattern was measured using a shape measurement laser microscope (“VK-X100” manufactured by Keyence Corporation). At this time, the surface roughness was measured by cutting off at λc (contour curve filter) = 0.08 mm in accordance with JIS B0601: 2001 (ISO 4287, 1997). The results are shown in Table 2.

In the laminates of Examples 1 to 3, the metal silver layer was able to achieve a volume resistivity of 5 μΩ · cm or less and a surface roughness of 70 nm or less with good reproducibility. In contrast, in the laminates of Comparative Examples 1 to 3, the metal silver layer could not achieve a volume resistivity of 5 μΩ · cm or less and a surface roughness of 70 nm or less.

[Examples 4, 6, and 7]
(Preparation of silver ink composition)
A silver ink composition was prepared in the same manner as in Example 1 except that each component and the blending amount thereof at the time of preparing the silver ink composition were as shown in Table 3. The amount (number of moles) of silver carboxylate was the same as in Example 1. The results are shown in Table 4.
In Table 3, “-” in the column of the blending component means that the component is not blended.

In Table 3, “nitrogen-containing compound (molar ratio)” means the compounding amount (number of moles) of nitrogen-containing compound per mole of silver carboxylate ([number of moles of nitrogen-containing compound] / [carvone] Number of moles of acid silver]). Similarly, the “reducing compound (molar ratio)” is also the blending amount (number of moles) of the reducing compound per mole of silver carboxylate (number of moles of reducing compound) / [number of moles of silver carboxylate]. ] "And" alcohol (molar ratio) "means the blending amount (number of moles) of alcohol per mole of silver carboxylate ([number of moles of alcohol] / [number of moles of silver carboxylate]). means.

(Production and evaluation of laminate)
Using the silver ink composition obtained above, instead of baking (heat treatment) at 80 ° C. for 1 hour, after heat treatment in an oven at 80 ° C. for 1 minute, the relative humidity of 99% was further increased. A laminate was prepared and evaluated in the same manner as in Example 1 except that it was heated (baked) at 80 ° C. for 2 minutes under humidified conditions. The results are shown in Table 5.

[Example 5]
(Preparation of silver ink composition)
The blending amount of each component at the time of preparing the silver ink composition is as shown in Table 3, and the stirring shape of the mechanical stirrer is replaced with the anchor shape shown in FIG. A silver ink composition was prepared in the same manner as in Example 1 except that the type) was used. FIG. 3 is a schematic diagram showing an anchor-shaped (max blend type) stirring blade 300. The amount (number of moles) of silver carboxylate was the same as in Example 1. The results are shown in Table 4.

The stirring blade 300 shown in FIG. 3 has a stirring blade diameter of about 95% with respect to the inner diameter (diameter) of the beaker, and the distance between the inner peripheral surface of the beaker and the outer side 320a of the forced flow generation blade portion 320 is about It was 2 mm. Moreover, the rotation speed of the stirring blade 300 was set to 300 rpm.

(Production and evaluation of laminate)
Using the silver ink composition obtained above, instead of baking (heat treatment) at 80 ° C. for 1 hour, after heat treatment in an oven at 80 ° C. for 1 minute, the relative humidity of 99% was further increased. A laminate was prepared and evaluated in the same manner as in Example 1 except that it was heated (baked) at 80 ° C. for 2 minutes under humidified conditions. The results are shown in Table 5.

[Example 8]
(Preparation of silver ink composition)
Add 2-methylacetoacetic acid silver to 2-ethylhexylamine (1.5-fold molar amount with respect to silver 2-methylacetoacetate described later) in a beaker so that the liquid temperature is 50 ° C. or less. The mixture was stirred for 15 minutes to obtain a liquid material. As the stirring blade of the mechanical stirrer, the same anchor shape as in Example 1 was used.
To this liquid, formic acid (0.4 times molar amount with respect to silver 2-methylacetoacetate) was added dropwise over 30 minutes so that the temperature of the reaction solution was 50 ° C. or lower. After completion of the formic acid dropwise addition, the reaction solution was further stirred at 25 ° C. for 1 hour, and while maintaining the temperature at 25 ° C., 3,5-dimethyl-1-hexyn-3-ol (“Surfinol 61” manufactured by Air Products Japan Co., Ltd.) was used. ”(Hereinafter abbreviated as“ DMHO ”) (0.04 times the molar amount with respect to silver 2-methylacetoacetate) was added, and the reaction liquid was further stirred for about 2 minutes to obtain a silver ink composition. . The amount (number of moles) of silver carboxylate was the same as in Example 1. The results are shown in Table 4.

(Production and evaluation of laminate)
The same as Example 1 except that the silver ink composition obtained above was used, and that it was baked (heated) at 120 ° C. for 1 hour instead of baked (heated) at 80 ° C. for 1 hour. Then, a laminate was prepared and evaluated. The results are shown in Table 5.

[Example 9]
(Preparation of silver ink composition, preparation and evaluation of laminate)
A silver ink composition was produced, and a laminate was produced and evaluated in the same manner as in Example 8 except that the components and the blending amounts thereof when producing the silver ink composition were as shown in Table 3. The results are shown in Table 5.

In the laminates of Examples 4 and 6 to 9, even if the type of the silver ink composition was changed, in the laminate of Example 5, the silver ink composition was prepared using stirring blades having different anchor shapes. In both cases, the metallic silver layer was able to achieve a volume resistivity of 5 μΩ · cm or less and a surface roughness of 70 nm or less.

According to the present invention, a laminate comprising a substrate and a metallic silver layer formed on the substrate, which can be produced without performing a heat treatment at a high temperature, It is possible to provide a laminate that exhibits sufficiently reduced volume resistivity and surface roughness with good reproducibility.

100, 200, 300 Stirring blade 110, 210, 310 Drive shaft 120, 220, 320 Forced flow generating blade portion 120a, 320a Outer side 130 Connecting portion 330 First connecting portion 340 Second connecting portion 350 Third connecting portion

Claims (5)

1. A laminate comprising a substrate and a metal silver layer formed on the substrate, wherein the metal silver layer has a volume resistivity of 5 μΩ · cm or less, and a surface roughness of the metal silver layer is 70 nm or less. .
2. The metallic silver layer is formed by solidifying a silver ink composition attached on the base material,
   The silver ink composition is
   Silver carboxylate having a group represented by the formula “—COOAg”;
   One or more nitrogen-containing compounds selected from the group consisting of an amine compound having 25 or less carbon atoms, a quaternary ammonium salt having 25 or less carbon atoms, ammonia and an ammonium salt obtained by reacting the amine compound or ammonia with an acid;
   A mixture of oxalic acid, hydrazine and one or more reducing compounds selected from the group consisting of compounds represented by the following general formula (5) and one or both of alcohols in a stirring vessel The laminate according to claim 1, which is produced by a production method including a step of stirring by rotating the material.
   HC (═O) —R ²¹ (5)
   (Wherein R ²¹ represents an alkyl group having 20 or less carbon atoms, an alkoxy group, or an N, N-dialkylamino group, a hydroxyl group, or an amino group.)
3. The stirring blade includes a drive shaft, a forced flow generating blade portion having an outer side that rotates and moves in the vicinity of the inner peripheral surface of the stirring tank, and a connecting portion that connects the drive shaft and the forced flow generating blade portion. The laminate according to claim 2, which is provided.
4. The laminate according to any one of claims 1 to 3, wherein the base material has a thickness of 10 to 5000 µm.
5. The laminate according to any one of claims 1 to 4, wherein the metal silver layer has a thickness of 0.5 to 20 µm.

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