TW201819546A - Conductive film composite and production method thereof - Google Patents

Abstract

A conductive film composite and a production method thereof are provided. The conductive film composite includes a substrate and a conductive film. Even though a substrate with low thermal resistance or glass substrate is used, the conductive film composite still has good adhesiveness of the conductive film with respect to the substrate and excellent conductivity and thermal resistance of the conductive film. The invention relates to a conductive film composite, including: a substrate; a resin layer formed on at least one portion of the substrate; and a conductive film formed on at least one portion of the resin layer, and the conductive film is a sintered body of fine silver particles, and the resin layer has a layer thickness of 1 [mu]m or less.

Description

Conductive coating composite and manufacturing method thereof

The present invention relates to a conductive coating composite which can be preferably used for wiring of a semiconductor integrated circuit or the like, wiring of a printed wiring board, transparent electrode, and wiring or electrode with respect to an organic thin film transistor substrate, and manufacturing thereof In a method, the conductive coating composite has a substrate and a conductive coating.

There has been known a method in which a metal thin film is formed on the entire surface of a substrate by sputtering or vapor deposition, and then an unnecessary portion is etched by photolithography to form a desired conductive film pattern. However, this method requires the use of an expensive vacuum device in addition to the complicated steps.

Therefore, a method for forming a conductive film pattern which is simpler and cheaper has been demanded, and in recent years, a method using a printing method such as a relief printing method, a gravure printing method, a screen printing method, or an inkjet printing method has been proposed. Further, as a printing method capable of forming a higher-definition pattern, a method using a reverse printing method or a micro-contact printing method has been proposed, and conductive inks, insulating inks, resistive inks, and the like suitable for the printing methods have been developed. Various inks. Here, particular attention is paid to a low-temperature sinterable conductive ink using silver fine particles.

A method for producing coated metal fine particles, which comprises the first step of mixing an amine mixed solution with a metal compound containing a metal atom, is disclosed in Patent Document 1 (Japanese Laid-Open Patent Publication No. 2012-162767). Forming a wrong compound comprising the metal compound and an amine, the amine mixed solution comprising an alkylamine having 6 or more carbon atoms and an alkylamine having 5 or less carbon atoms; and a second step of heating the wrong compound It is decomposed to generate metal microparticles.

In the above-described Patent Document 1, in the process of producing the coated metal fine particles by the metal amine complex decomposition method, the wrong compound of the amine and the metal compound can be smoothly produced, and the time required for the production can be shortened. Further, since various amines can be used depending on the use of the coated metal fine particles or the like, it is possible to provide coated metal fine particles which can be smoothly sintered at a temperature of, for example, 100 ° C or lower, and such as polyethylene terephthalate (Polyethylene). Conductive films and conductive wirings can also be formed on terephthalate, PET) and polypropylene-based plastic substrates with low heat resistance.

Further, a method for producing silver nanoparticles is disclosed in Patent Document 2 (Japanese Laid-Open Patent Publication No. 2013-142173), which comprises: preparing an amine mixed solution containing an aliphatic hydrocarbon group and an amine group, and the fat The aliphatic hydrocarbon monoamine (A) having a total carbon number of 6 or more and an aliphatic hydrocarbon monoamine (B) containing an aliphatic hydrocarbon group and an amine group, and the total number of carbons of the aliphatic hydrocarbon group is 5 or less, The amine (A) and the amine (B) are contained in a ratio of 5 mol% or more and less than 20 mol% of the amine (A), and more than 80 mol% and 95 mol% or less of the amine (B). The silver compound is mixed with the amine mixture to form a wrong compound containing a silver compound and an amine; the wrong compound is heated to thermally decompose to form silver nanoparticles.

In Patent Document 2, silver nanoparticle can be obtained by using an amine mixed liquid containing an aliphatic hydrocarbon monoamine (A) having a total carbon number of 6 or more and an aliphatic hydrocarbon monoamine (B) having a total carbon number of 5 or less. Proper stabilization.

Further, a conductive substrate having a conductive coating layer having excellent adhesion to a substrate is also proposed. For example, a translucent conductive material is disclosed in Patent Document 3 (Japanese Laid-Open Patent Publication No. 2008-149681). a substrate having a fine line pattern and a transparent conductive layer on the support, the fine line pattern comprising a conductive metal containing developed silver, and having a swelling relative to water between the support and the fine line pattern Easy adhesion layer with a moisture content of less than 60%.

In Patent Document 3, an easy-adhesion layer is provided between the support and the fine-line pattern layer, and the swelling ratio of the layer with respect to water is controlled to be less than 60%, whereby durability or adhesion in a high-temperature and high-humidity environment is achieved. The property is remarkably improved, and it is easy to adjust the coexistence of the thin line shape (thinness and width) and conductivity or the coexistence of the thin line shape (thinness and width) and light transmittance.

Further, a method for producing a conductive material, comprising: (1) applying a resin layer-forming composition (b) to an insulating group, is disclosed in Japanese Laid-Open Patent Publication No. 2014-196556. a step of forming a resin layer (B) on the material (A); (2) applying a dispersion liquid (C) to the resin layer (B) obtained in (1) to form a non-conductive layer (D) In the step, the dispersion (C) contains 0.5% by mass or more of a group consisting of gold, silver, copper, and platinum, which is protected by a compound (c1) having a nitrogen atom, a sulfur atom, a phosphorus atom, and an oxygen atom. One or more metal fine particles (c2) in the group; and (3) a step of forming a conductive layer (E) by electroless plating the substrate having the non-conductive layer (D) obtained in (2), The method for producing a conductive material is characterized in that the resin layer-forming composition (b) is a resin layer containing a urethane resin (b1), a vinyl polymer (b2), and an aqueous medium (b3). Use the composition.

In Patent Document 4, a non-conductive layer containing metal fine particles of gold, silver, copper, or platinum protected by a specific compound can be formed by forming a resin layer on various insulating substrates. It is easy to obtain by a coating method, and the non-conductive layer exhibits excellent catalyst activity of electroless plating and functions as a foothold of a plating film that causes strong adhesion, so that it can be reduced in cost without a vacuum apparatus. A high-performance conductive material, a printed wiring board substrate, and a printed wiring board that can be used in the field of high-density mounting are manufactured. [Prior Art Document] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Publication No. 2014-196556

[Problems to be Solved by the Invention] When the silver nanoparticles described in Patent Document 1 and Patent Document 2 are used, the conductive coating layer obtained by firing at a low temperature has excellent conductivity. For example, the conductive coating layer is formed on a non-heat-resistant substrate such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) or a glass substrate. In this case, it is difficult to ensure adhesion to the substrate.

In the conductive material described in Patent Document 3 and Patent Document 4, the conductivity of the conductive coating layer with respect to the substrate is good, but the conductivity of the conductive coating layer may be impaired.

Further, at the time of mounting, the conductive coating layer is required to have heat resistance (for example, it is kept at 180 ° C for 1 minute), and as a result, it is extremely difficult to form all of the heat resistance and the adhesion to the substrate and conductivity. Conductive coating.

Therefore, an object of the present invention is to provide an excellent adhesion between a conductive coating and a substrate and a conductive coating even when a substrate or a glass substrate having low heat resistance is used. A conductive coating composite having conductivity and heat resistance, and a method for producing the same, the conductive coating composite having a substrate and a conductive coating. [Means for solving the problem]

In order to achieve the above object, the inventors of the present invention have conducted intensive studies, and as a result, have found that the present invention is extremely effective in achieving the object, and the present invention has been accomplished in such a manner that in order to obtain excellent adhesion to a substrate, And a conductive coating composite which exhibits excellent electrical conductivity and excellent heat resistance with respect to a substrate or a glass substrate having low heat resistance, and a resin having a specific thickness is formed on the substrate in the form of an adhesive layer. A conductive coating is formed between the conductive coating and a specific silver nanoparticle dispersion.

That is, the present invention provides a conductive coating composite characterized by comprising: a substrate; a resin layer formed on at least a portion of the substrate; and a conductive coating formed on at least a portion of the resin layer The conductive coating layer is formed of silver fine particles, and the resin layer has a film thickness of 1 μm or less.

In the conductive coating composite of the present invention, since the resin layer functions as an adhesion layer between the substrate and the conductive coating layer, the substrate and the conductive coating layer have good adhesion. In addition, when the thickness of the resin layer is 1 μm or less, the influence of swelling and shrinkage of the resin layer is reduced, and excellent heat resistance can be imparted to the conductive coating layer.

Further, when the resin layer is thicker than 1 μm, problems due to the characteristics of the resin layer may occur. Specifically, the conductive coating excessively expands and contracts by the flexibility of the resin layer, and as a result, defects (broken lines) are formed in the conductive coating layer. Further, there is a case where deterioration of transparency due to a thick resin layer, whitening due to moisture absorption or the like, yellowing due to heat, and the like may occur. Here, by setting the film thickness of the resin layer to 1 μm or less, it is possible to minimize these adverse effects. In addition, by setting the film thickness of the resin layer to 1 μm or less, it is not advantageous to use a material required or more, which is advantageous in terms of cost.

Further, a more preferable thickness of the resin layer is 0.05 μm to 0.8 μm, and an optimum film thickness is 0.1 μm to 0.5 μm. When it is less than 0.05 μm, the effect of the resin layer may not be sufficiently exhibited, and the adhesion may be poor.

In the conductive coating composition of the present invention, the resin layer is not particularly limited as long as it exhibits good adhesion to the substrate, but it is preferably in order to exhibit excellent adhesion to the substrate. In order to have a functional group such as a carboxyl group or a hydroxyl group, for example, a polyvinyl alcohol-based resin (including polyvinyl butyral) or polyvinylpyrrolidone may be used. Further, it is preferred that the main component of the resin layer is a polyamino group. As the acid ester resin, a polymer having an isocyanate group protected by a blocking agent and/or a polymer containing an oxazoline group is added as a crosslinking agent to the polyurethane resin. The softness of the resin layer can be controlled by adding the crosslinking agent to the polyurethane resin.

Further, in the conductive coating composite of the present invention, it is preferred that the solid content of the crosslinking agent relative to the solid content of the polyurethane resin is 10% by weight or less. If the amount of the solid component of the crosslinking agent relative to the solid content of the polyurethane resin is more than 10% by weight, the specific functional group contained in the polyurethane resin excessively reacts with the crosslinking agent. Therefore, in addition to the impaired flexibility of the resin layer, the adhesion between the resin layer and the substrate and the conductive coating layer tends to be impaired.

Further, the detailed reason is not clear, but the reason is considered to be that the polyurethane resin used as the adhesion layer has -COO-H, -COOR, -COO ^- NH ⁺ R ₂ and -COO ^- NH ₄ ⁺ ( Wherein R and R ₂ each independently represent a linear or branched alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkylene group which may have a substituent, an oxygen alkyl group which may have a substituent An aryl group which may have a substituent, an aralkyl group which may have a substituent, a heterocyclic group which may have a substituent, an alkoxy group which may have a substituent, an alkoxycarbonyl group which may have a substituent, may have a substituent Any of the functional groups in the sulfhydryl group improves the adhesion between the resin layer and the substrate and the resin layer and the conductive coating layer. In addition, as long as the polyurethane resin is used, the durability in a high-temperature and high-humidity environment is good, and this is also preferable.

Further, in the conductive coating composite of the present invention, the conductive coating layer is formed of silver fine particles and is sintered by external heating or the like, thereby having the same degree of conductivity as the silver fine particles inherently. Good conductivity. The reason why the good conductivity is exhibited is not clear, but it is considered to be due to the excellent deformation property of the resin layer used as the adhesion layer.

The resin layer preferably has an elongation at break of 600% or more. By the flexibility and shrinkage expansion property, the difference in thermal expansion coefficient between the substrate and the conductive coating layer can be alleviated in the process of sintering the silver fine particles. As a result, the sintering of the silver fine particles proceeds smoothly, and a conductive coating layer having excellent conductivity can be obtained.

Further, in the conductive coating composite of the present invention, it is preferred that the polyurethane resin is an aqueous polyurethane resin. The water-based polyurethane resin has a low odor and can prevent deterioration of the working environment and reduction in environmental load.

Further, in the conductive coating composite of the present invention, it is preferable that the resin layer is formed by applying the aqueous polyurethane resin dissolved in a solvent to the substrate. Usually, the aqueous polyurethane resin is present in a state of being dispersed in water (latex), and a solvent is volatilized to form a film. However, the film may be formed by the particle diameter of the latex depending on film formation conditions.

Here, in the case where a thin resin layer is to be formed, there is a problem that the surface roughness becomes large. On the other hand, by dissolving an aqueous polyurethane resin in a solvent (for example, ethanol or acetone), the latex is broken into a uniform solution, and thus film formation properties (especially film uniformity in a film) improve.

Further, in the conductive coating composite of the present invention, it is preferable that the conductive coating layer is formed of a dispersion of silver fine particles, the silver fine particle dispersion comprising: the silver fine particles; a short-chain amine; a solvent And a dispersing agent for dispersing the silver fine particles.

Further, in the conductive coating composite of the present invention, the short-chain amine preferably has a carbon number of 5 or less, and the solvent is preferably a highly polar solvent, and the dispersant preferably has an acid value. The partition coefficient logP of the short-chain amine is preferably from -1.0 to 1.4.

The silver fine particle dispersion is a low-sintering silver fine particle dispersion in which silver fine particles are uniformly dispersed in a plurality of solvents (particularly, a highly polar solvent), and the silver fine particle composite is sintered to form a conductive coating layer. Thereby, a conductive coating having good conductivity can be formed at a low temperature.

The amine groups within one molecule of the amine have a relatively high polarity and are liable to generate hydrogen bond interactions, and portions other than the functional groups have relatively low polarities. Further, the amine groups are likely to exhibit basic properties, respectively. Therefore, if the amine is locally present (attached) to at least a part of the surface of the silver fine particles (that is, if at least a part of the surface of the silver fine particles are coated), the organic component can be sufficiently affinityd with the inorganic particles to prevent aggregation of the silver fine particles. (Improve dispersion). That is, the functional group of the amine is adsorbed on the surface of the silver fine particles with an appropriate strength, and the silver fine particles are prevented from coming into contact with each other, thereby contributing to the stability of the silver fine particles in the storage state. It is also considered that the surface of the silver fine particles is moved and/or volatilized by heating, thereby promoting the fusion of the silver fine particles.

In addition, by setting the amine constituting the silver fine particle dispersion to a short-chain amine having a carbon number of 5 or less, it is possible to easily remove the amine adhering to at least a part of the surface of the silver fine particles by heating, and to secure the silver fine particles. Good low-temperature sinterability (for example, sinterability at 100 ° C to 350 ° C).

Further, the reason why the partition coefficient logP of the short-chain amine is -1.0 to 1.4 is that if the partition coefficient logP is less than -1.0, the polarity of the short-chain amine is too high, so that the reduction of silver proceeds rapidly, and it becomes difficult to control the silver fine particles. When the distribution coefficient logP exceeds 1.4, the polarity of the amine coordinated to the silver is low, and thus it becomes difficult to disperse in the highly polar solvent.

The partition coefficient logP refers to the octanol/water partition coefficient using n-octanol and water as a solvent, and the concentration Co in octanol and the concentration Cw in water are respectively determined, and the common logarithm logP of the concentration ratio P=Co/Cw is calculated as Partition coefficient. Therefore, the partition coefficient logP refers to an index indicating whether or not the silver fine particles can be dispersed by a certain range of polar solvents. The method for measuring the partition coefficient logP is not particularly limited, and for example, a flask oscillating method, a high performance liquid chromatography (HPLC) method, and a quantitative structure-activity relationship algorithm can be used. For calculation, etc., the literature values published on the website of the National Center for Biotechnology Information can also be used.

Further, the silver fine particle dispersion is characterized by comprising a dispersant having an acid value (that is, a dispersant having an acid value for dispersing silver fine particles) added after silver fine particle synthesis. The "dispersant having an acid value" as used herein includes all dispersants which do not have an amine value or a hydroxyl value as an adsorption group or a functional group. By using the dispersant, the dispersion stability of the silver fine particles in the solvent can be improved. The acid value of the dispersant is preferably from 5 to 200, and the dispersant preferably has a functional group derived from phosphoric acid. The reason why the "dispersant having an acid value" is preferable is not necessarily clear, but the present inventors believe that it is possible to adsorb in a denser form not only by adsorption to a metal but also by interaction with a short-chain amine. It not only has low-temperature sinterability but also exhibits high dispersibility.

In the case where the silver fine particles are to be dispersed in a highly polar solvent to be described later, it is generally effective to use a highly polar dispersant. For example, it is considered that a short-chain amine having a smaller logP is used, but a short-chain amine generally exhibits reducibility and may not be able to maintain a suitable reaction rate. Specifically, there is a case where the reaction rate is excessively increased and silver fine particles having excellent dispersibility cannot be formed. Therefore, by adding a highly polar dispersant after silver fine particle synthesis, the silver fine particles can maintain the original state and only improve the compatibility with the dispersion medium (surface modification).

When the acid value of the dispersing agent is 5 or more, the amine is coordinated to the amine, and the surface of the particle starts to adsorb under the acid-base interaction with the metal substance which becomes alkaline, and if it is 200 or less, since it does not have a site which is excessively adsorbed, Therefore, it is preferred to adsorb in an appropriate form. Further, since the dispersing agent has a functional group derived from phosphoric acid, and phosphorus P interacts with the metal M via the oxygen O and is mutually attracted, it is most effective for adsorption to a metal or a metal compound, and can be minimized in adsorption. It is preferred to obtain an appropriate amount of dispersibility. Here, the "acid value" is represented by the number of mg of potassium hydroxide required to neutralize the acidic component contained in 1 g of the sample. The method for measuring the acid value may be an indicator method (p-naphtholbenzein indicator) or a potentiometric titration method. ×ISO6618-1997: Corresponding to the neutralization value test method using the indicator titration method → indicator titration method (acid value) ×ISO6619-1988: Corresponding to potentiometric titration (acid value) → potential difference titration (acid value)

The silver fine particle dispersion may further contain an acid-valent dispersing agent (protective dispersing agent) as a protective agent added before the silver fine particle synthesis. Here, the "protective dispersant" may be the same as the "acid-valent dispersant" added after the silver fine particles are synthesized.

Further, in the silver fine particle dispersion, a plurality of solvents, particularly a highly polar solvent, can be used as the solvent. The highly polar solvent means that it is difficult to be compatible with a low polar solvent such as hexane or toluene, and is usually water or an alcohol having a short carbon number. In the present invention, it is more preferred to use an alcohol having 1 to 6 carbon atoms. By providing an alcohol having 1 to 6 carbon atoms as a highly polar solvent, it is possible to avoid an abnormality in the case of using a low-polarity solvent, and for example, it is possible to prevent the solvent from entering the resin layer of the substrate when the silver fine particle dispersion is laminated on the resin. Here, an alkoxyamine is preferably used in the amine. By setting the amine to an alkoxyamine, the silver fine particles can be well dispersed in a highly polar solvent.

The particle size of the silver fine particles constituting the silver fine particle dispersion is preferably a nanometer size which is lowered in melting point, preferably from 1 nm to 200 nm, and may also contain micron-sized particles as needed.

In addition, the present invention also provides a method for manufacturing a conductive coating composite, comprising: a first step of coating a resin on at least a portion of a substrate to form a resin layer; and a second step of dispersing the silver particles The body is coated on at least a portion of the resin layer; and in the third step, the silver fine particles contained in the silver fine particle dispersion are sintered by external heating to form a conductive coating layer.

By forming a conductive coating layer by application of silver fine particle dispersion and external heating, a conductive coating layer having excellent conductivity can be formed at a low temperature, and a substrate having low heat resistance can also exhibit good conductivity. Conductive coating composite.

Further, in the method for producing a conductive coating composite of the present invention, by using a resin layer as an adhesion layer, adhesion between the resin layer and the substrate and the resin layer and the conductive coating layer can be improved.

Further, in the method for producing a conductive coating composite of the present invention, it is preferred that the main component of the resin layer is a polyurethane resin, and an isocyanate group is added to the polyurethane resin. The polymer protected by the blocking agent and/or the polymer containing the oxazoline group serves as a crosslinking agent. The softness of the resin layer can be controlled by adding the crosslinking agent to the polyurethane resin. That is, it is preferred to use a polyurethane resin composition containing a polyurethane resin and a crosslinking agent.

The solid content of the crosslinking agent relative to the solid content of the polyurethane resin is preferably set to 10% by weight or less. If the amount of the solid component of the crosslinking agent relative to the solid content of the polyurethane resin is more than 10% by weight, the specific functional group contained in the polyurethane resin excessively reacts with the crosslinking agent. Therefore, in addition to the impaired flexibility of the resin layer, the adhesion between the resin layer and the substrate and the conductive coating layer tends to be impaired.

By using, for example, a polyurethane resin having an elongation at break of 600% or more in the resin layer, in the third step of sintering the silver fine particles, the difference in thermal expansion coefficient between the substrate and the conductive coating layer can be sufficiently alleviated. As a result, the sintering of the silver fine particles proceeds smoothly, and a conductive coating layer having excellent conductivity can be obtained.

Further, in the method for producing a conductive coating composite of the present invention, it is preferred to use an aqueous polyurethane resin as the polyurethane resin. The water-based polyurethane resin has a low odor and can prevent deterioration of the working environment and reduction in environmental load.

Further, in the method for producing a conductive coating composite of the present invention, it is preferred that the thickness of the resin layer be 1 μm or less. When the thickness of the resin layer is 1 μm or less, the influence of swelling and shrinkage of the resin layer is reduced, and excellent heat resistance can be imparted to the conductive coating layer. Further, the film thickness of the resin layer can be appropriately controlled depending on the number of revolutions of the spin coating, the amount of the diluent, and the like.

Further, in the method for producing a conductive coating composite according to the present invention, preferably, in the first step, the aqueous polyurethane resin dissolved in a solvent is applied to the substrate. The resin layer is formed on the upper side. Usually, the aqueous polyurethane resin is present in a state of being dispersed in water (latex), and a solvent is volatilized to form a film. However, the film may be formed by the particle diameter of the latex depending on film formation conditions.

Here, in the case where a thin resin layer is to be formed, there is a problem that the surface roughness becomes large. On the other hand, by dissolving an aqueous polyurethane resin in a solvent (for example, ethanol or acetone), the latex is broken into a uniform solution, and thus film formation properties (especially film uniformity in a film) improve.

Further, in the method for producing a conductive coating composite according to the present invention, it is preferable that the silver fine particle dispersion is a silver fine particle dispersion comprising: the silver fine particles; and having a carbon number of 5 or less. a short-chain amine; a highly polar solvent; and an acid-valent dispersant for dispersing the silver microparticles, and the short-chain amine has a partition coefficient logP of from -1.0 to 1.4.

As described above, the silver fine particle dispersion is a silver fine particle dispersion having low-temperature sinterability in which silver fine particles are uniformly dispersed in a plurality of solvents (particularly, a highly polar solvent), and thus coating of the substrate is easy (second step) The conductive coating layer is formed by sintering (third step) of the silver fine particle composite, whereby a conductive coating having good conductivity can be formed at a low temperature. [Effects of the Invention]

According to the conductive coating composite of the present invention and the method for producing the same, it is possible to provide a good adhesion of the conductive coating to the substrate even when a substrate or a glass substrate having low heat resistance is used. A conductive coating composite which is excellent in electrical conductivity and excellent in heat resistance, and a method for producing the same, the conductive coating composite having a substrate and a conductive coating.

Hereinafter, a preferred embodiment of the conductive coating composite of the present invention and a method for producing the same will be described in detail. In addition, in the following description, the repeated description may be omitted.

(1) Conductive coating composite Fig. 1 is a schematic cross-sectional view showing a conductive coating composite of the present embodiment. The conductive coating composite 1 of the present invention comprises: a substrate 2; a resin layer 4 formed on at least a portion of the substrate 2; and a conductive coating 6 formed on at least a portion of the resin layer 4.

Since the resin layer 4 is formed as an adhesion layer between the substrate 2 and the conductive coating layer 6, the conductive coating layer 6 and the substrate 2 have good adhesion.

(1-1) Substrate The substrate 2 is not particularly limited as long as it does not impair the effects of the present invention, and various conventionally known substrates can be used. As a material usable in the substrate 2, for example, polyamide (PA), polyimide (PI), polyamide imide (PAI), polyparaphenylene is exemplified. Polyethylene glycol (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and other polyesters, polycarbonate (Polycarbonate, PC), polyether oxime ( Polyether sulfone, PES), vinyl, fluororesin, liquid crystal polymer, ceramic or glass.

(1-2) Resin Layer The resin layer 4 has a film thickness of 1 μm or less. When the thickness of the resin layer 4 is 1 μm or less, the influence of swelling and shrinkage of the resin layer is reduced, and excellent heat resistance can be imparted to the conductive coating layer 6. Further, the resin layer 4 preferably has a film thickness of 0.05 μm to 0.8 μm, and an optimum film thickness of 0.1 μm to 0.5 μm.

When the resin layer 4 is thicker than 1 μm, problems caused by the characteristics of the resin layer 4 may occur. Specifically, the conductive coating layer 6 expands and contracts excessively by the flexibility of the resin layer 4, and as a result, defects (broken lines) are formed in the conductive coating layer 6. Further, deterioration of transparency due to the thick resin layer 4, whitening due to moisture absorption or the like, yellowing due to heat, and the like may occur. Here, by setting the film thickness of the resin layer 4 to 1 μm or less, it is possible to minimize these adverse effects. In addition, by setting the film thickness of the resin layer 4 to 1 μm or less, there is no need to use a material required or more, which is advantageous in terms of cost.

The resin layer 4 is not particularly limited as long as it does not impair the effects of the present invention, and various conventionally known resins can be used. However, it is preferred that the main component is a polyurethane resin and the polyurethane is used. A polymer in which an isocyanate group is protected by a blocking agent and/or a polymer containing an oxazoline group is added as a crosslinking agent to the resin. The flexibility of the resin layer 4 can be controlled by adding the crosslinking agent to the polyurethane resin.

Further, the solid content of the crosslinking agent relative to the solid content of the polyurethane resin is preferably within 10% by weight. If the amount of the solid component of the crosslinking agent relative to the solid content of the polyurethane resin is more than 10% by weight, the specific functional group contained in the polyurethane resin excessively reacts with the crosslinking agent. Therefore, in addition to the impaired flexibility of the resin layer 4, the adhesion between the resin layer 4 and the base material 2 and the conductive coating layer 6 tends to be impaired.

Further, the main component of the resin layer 4 is more preferably a polyurethane resin having a breaking elongation of 600% or more, and the polyurethane resin preferably has -COO-H, -COOR, -COO ^- NH ⁺ R ₂ and -COO ^- NH ₄ ⁺ (wherein R and R ₂ each independently represent a linear or branched alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, and a substituent which may have a substituent An alkyl group, an oxoalkyl group which may have a substituent, an aryl group which may have a substituent, an aralkyl group which may have a substituent, a heterocyclic group which may have a substituent, an alkoxy group which may have a substituent, may have Any one of the functional group of the alkoxycarbonyl group of the substituent and the fluorenyl group which may have a substituent has a functional group represented by the following.

In the conductive coating composite 1, since the resin layer 4 functions as an adhesion layer between the substrate 2 and the conductive coating layer 6, the substrate 2 and the conductive coating layer 6 have good adhesion. Further, the detailed reason is not clear, but the polyurethane resin used as the adhesion layer has the specific functional group, the resin layer 4 and the substrate 2, and the resin layer 4 and the conductive coating layer 6. The adhesion is improved.

In addition, when the polyurethane resin which is a main component of the resin layer 4 has a characteristic of breaking elongation of 600% or more, it is rich in flexibility and shrinkage expansion property, so that silver fine particles are sintered to form a conductive coating. In the process of the layer 6, the difference in thermal expansion coefficient between the substrate 2 and the conductive coating 6 can be alleviated. As a result, it is considered that the sintering of the silver fine particles proceeds smoothly, and the conductive coating layer 6 having excellent conductivity can be obtained.

The polyurethane resin is preferably an aqueous polyurethane resin. The water-based polyurethane resin has a low odor and can prevent deterioration of the working environment and reduction in environmental load.

As the polyurethane resin, any of polyurethane-based, ether-based or polycarbonate-based polyurethane resins may be used, but it is preferred to use an ether-based or polycarbonate-based compound having excellent hydrolysis resistance. Polyurethane resin.

More specifically, as the polyurethane resin, a superflex series manufactured by the first industrial pharmaceutical company: 300, 460, 470, 500M, 740, E-2000, E- can be preferably used. 4800, or Hydran series of DiCai (DIC) Co., Ltd.: HW-312B, HW-311, AP-10, AP-70, urethane resin latex manufactured by Sanyo Chemical: Parmaline (Parmalin) UA-200, Uprene UXA-307, etc.

Further, since the polyurethane resin used as the main component of the resin layer 4 has a specific functional group, the flexibility of the resin layer 4 can be controlled by adding a crosslinking agent that reacts with the functional group. Examples of applicable functional groups include an amine group, an isocyanate group, an oxazoline group, and a carbodiimide group. Here, the reaction between the functional group and the crosslinking agent is preferably carried out at the time of film formation. Therefore, a blocked isocyanate group or an oxazoline group which is difficult to carry out at normal temperature is preferably used.

However, when a crosslinking agent is added, the specific functional group contained in the polyurethane resin excessively reacts with the crosslinking agent, and thus the flexibility of the resin layer 4 is impaired. In addition, the adhesion between the resin layer 4 and the substrate 2 and the conductive coating layer 6 tends to be impaired. Therefore, it is preferred to set the solid content of the crosslinking agent relative to the solid content of the polyurethane resin to 10% or less.

The crosslinking agent is not particularly limited as long as it does not impair the effects of the present invention, and various conventionally known crosslinking agents can be used. For example, the Elastron series BN-69 manufactured by Daiichi Kogyo Co., Ltd. can be used. , BN-77, or the Epocros series of WS-300, WS-500, WS-700 made by Japan Catalyst.

The film formation method of the resin layer 4 is not particularly limited, and for example, immersion, spray type, bar coating type, spin coating, slit die coating type, air knife type, reverse roll coating type, gravure coating type, or the like can be used. Curtain flow and so on.

In addition, the film formation temperature is not particularly limited, and a temperature equal to or higher than the minimum film formation temperature of the composition used as the raw material of the resin layer 4 may be used. Further, heat treatment may be performed at a temperature equal to or lower than the heat resistance temperature of the substrate 2 as needed.

(1-3) Conductive Coating The conductive coating layer 6 is formed of silver fine particles and is a sintered body formed by externally heating it, and has a good electrical conductivity similar to the conductivity originally possessed by the silver fine particles. Sex. The thickness of the conductive coating layer 6 is preferably from 0.1 μm to 2 μm. If it is less than 0.1 μm, the thickness may be too thin to obtain sufficient conductivity. Even if it exceeds 2 μm, there is no problem in terms of conductivity, but the amount of use is increased, so the cost is high and the temperature is not good.

The silver fine particle dispersion for forming the conductive coating layer 6 is not particularly limited as long as the effect of the present invention is not impaired, and a plurality of conventionally known silver fine particle dispersions can be used, and the following silver fine particle dispersion is preferably used. A silver-containing fine particle, a short-chain amine having a carbon number of 5 or less, a highly polar solvent, and an acid-valent dispersant for dispersing silver fine particles, and a distribution coefficient logP of a short-chain amine of -1.0 to 1.4.

The silver fine particle dispersion is a low-sintering silver fine particle dispersion in which silver fine particles are uniformly dispersed in a plurality of solvents (particularly, a highly polar solvent), and the conductive coating layer 6 is formed by sintering of the silver fine particle composite. Thereby, the conductive coating 6 having good conductivity can be formed at a low temperature. Further, the short-chain amine contained in the silver fine particles interacts with a specific functional group of the polyurethane resin used as the main component of the resin layer 4, and exhibits good adhesion.

(1-3-1) Silver fine particle dispersion The silver fine particle dispersion of the present embodiment contains silver fine particles, a short-chain amine having 5 or less carbon atoms, and a highly polar solvent. Hereinafter, each component and the like will be described.

(A) Silver fine particles The average particle diameter of the silver fine particles in the silver fine particle dispersion of the present embodiment is not particularly limited as long as it does not impair the effects of the present invention, and it is preferred to have an average particle such as a melting point. For example, the diameter is 1 nm to 200 nm. Especially preferred is 2 nm to 100 nm. When the average particle diameter of the silver fine particles is 1 nm or more, not only the silver fine particles have good low-temperature sinterability, but also the production of silver fine particles is not expensive, so that it is practical. Further, when the thickness is 200 nm or less, the dispersibility of the silver fine particles is less likely to change with time, which is preferable.

For the silver fine particle dispersion, for example, in consideration of the problem of migration, a metal having an ionization sequence noble to hydrogen, that is, particles of gold, copper, platinum, palladium or the like may be added.

Further, the particle size of the silver fine particles in the silver fine particle dispersion of the present embodiment may not be fixed. In addition, when the silver fine particle dispersion contains a dispersant or the like to be described later as an optional component, the metal particle component having an average particle diameter of more than 200 nm may be contained. However, if the aggregation does not occur, the present invention is not significantly impaired. The component of the effect may also include the metal particle component having an average particle diameter of more than 200 nm.

Here, the particle diameter of the silver fine particles in the silver fine particle dispersion of the present embodiment can be measured by a dynamic light scattering method, a small angle X-ray scattering method, or a wide-angle X-ray diffraction method. In order to show the decrease in the melting point of the silver fine particles having a nanometer size, the crystallite diameter determined by the wide-angle X-ray diffraction method is preferred. For example, in the wide-angle X-ray diffraction method, more specifically, RINT-Ultima III manufactured by Rigaku Electric Co., Ltd. can be used, and the diffraction method can be measured in the range of 30 to 80 in 2θ. In this case, the sample may be measured by thinning the surface of the glass plate having a pit having a depth of about 0.1 mm to 1 mm at the center portion. Further, when Jade manufactured by Rigaku Electric Co., Ltd. is used, the crystallite diameter (D) calculated by substituting the obtained half-value width of the diffraction spectrum into the Scherrer equation described below is used as The particle size can be. D = Kλ / Bcos θ Here, K: Scherrer constant (0.9), λ: wavelength of X-ray, B: half-value width around the ray, θ: Bragg angle.

(B) Short-chain amine having a carbon number of 5 or less In the silver fine particle dispersion of the present embodiment, a short-chain amine having 5 or less carbon atoms is adhered to at least a part of the surface of the silver fine particles. Further, the surface of the silver fine particles may be a trace amount of an organic substance originally contained as an impurity in the raw material, a trace amount of an organic substance mixed in a production process to be described later, a residual reducing agent which is not completely removed during the washing process, a residual dispersant, and the like. , a trace of organic matter attached.

The short-chain amine having a carbon number of 5 or less is not particularly limited as long as the partition coefficient logP is -1.0 to 1.4, and may be linear or branched, or may have a side chain. Examples of the short-chain amine include ethylamine (-0.3), propylamine (0.5), butylamine (1.0), and N-(3-methoxypropyl)propane-1,3-diamine (-0.6). ), 1,2-ethylenediamine, N-(3-methoxypropyl)formamide (-0.2), 2-methoxyethylamine (-0.9), 3-methoxypropylamine (-0.5) ), 3-ethoxypropylamine (-0.1), 1,4-butanediamine (-0.9), 1,5-pentanediamine (-0.6), pentanolamine (-0.3), aminoisobutanol (-0.8) and the like, among which alkoxyamine is preferably used.

The short-chain amine may be, for example, a compound containing a functional group other than an amine such as a hydroxyl group, a carboxyl group, an alkoxy group, a carbonyl group, an ester group or a mercapto group. Further, the amines may be used alone or in combination of two or more. In addition, the boiling point at normal pressure is preferably 300 ° C or lower, and particularly preferably 250 ° C or lower.

The silver particle dispersion of the present embodiment may contain a carboxylic acid in addition to the short-chain amine having 5 or less carbon atoms, insofar as it does not impair the effects of the present invention. The carboxyl group in one molecule of the carboxylic acid has a relatively high polarity, and an interaction using a hydrogen bond is easily generated, but a portion other than the functional group has a relatively low polarity. Further, the carboxyl group is liable to exhibit acidic properties. Further, in the silver particle dispersion of the present embodiment, at least a part of the surface of the silver fine particles (that is, at least a part of the surface of the silver fine particles coated) is partially present (attached), and the solvent and the silver fine particles can be sufficiently obtained. Affinity prevents aggregation of silver particles (enhanced dispersibility).

As the carboxylic acid, a compound having at least one carboxyl group can be widely used, and examples thereof include formic acid, oxalic acid, acetic acid, caproic acid, acrylic acid, octanoic acid, and oleic acid. A carboxyl group of a part of the carboxylic acid may also form a salt with the metal ion. Further, the metal ions may contain two or more kinds of metal ions.

The carboxylic acid may be, for example, a compound containing a functional group other than a carboxyl group such as an amino group, a hydroxyl group, an alkoxy group, a carbonyl group, an ester group or a fluorenyl group. In this case, the number of carboxyl groups is preferably at least the number of functional groups other than the carboxyl group. Further, the carboxylic acids may be used alone or in combination of two or more. In addition, the boiling point at normal pressure is preferably 300 ° C or lower, and particularly preferably 250 ° C or lower. Additionally, the amine forms a guanamine with the carboxylic acid. The guanamine group is also moderately adsorbed on the surface of the silver fine particles, and therefore a guanamine group may be attached to the surface of the silver fine particles.

When the silver fine particles and the organic substance adhering to the surface of the silver fine particles (the short-chain amine having a carbon number of 5 or less) constitute a colloid, the content of the organic component in the colloid is preferably 0.5% by mass. 50% by mass. When the content of the organic component is 0.5% by mass or more, the storage stability of the obtained silver fine particle dispersion tends to be good, and when it is 50% by mass or less, the silver fine particle dispersion is heated to obtain a calcined body. The tendency of good electrical conductivity. A more preferable content of the organic component is 1% to 30% by mass, and a more preferable content is 2% to 15% by mass.

(C) Highly polar solvent The silver fine particle dispersion of the present embodiment is one in which silver fine particles are dispersed in a plurality of highly polar solvents.

As the solvent, a plurality of highly polar solvents can be used within a range that does not impair the effects of the present invention. As the highly polar solvent, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, 2-butanol, pentanol, hexanol, isoamyl alcohol, decyl alcohol, nitromethane, acetonitrile, pyridine can be exemplified. , acetone cresol, dimethylformamide, dioxane, ethylene glycol, glycerin, phenol, p-cresol, propyl acetate, isopropyl acetate, tert-butanol, 1-pentanol, 2-pentyl Alcohol, 4-methyl-2-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 2-butanol, 1-hexanol, 2-hexanol 2-pentanone , 2-heptanone, 2-(2-ethoxyethoxy)ethyl acetate, 2-butoxyethyl acetate, 2-(2-butoxyethoxy)ethyl acetate, acetic acid- 2-methoxyethyl ester, 2-hexyloxyethanol, etc., but in the present invention, since the compatibility with the short-chain amine having 5 or less carbon atoms is good, it is preferred to use a carbon number of 1 to 6. alcohol. Further, these solvents may be used singly or in combination of two or more.

(D) Dispersant The silver particle dispersion of the present embodiment further includes a "dispersant having an acid value" added after the silver fine particles are dispersed in order to disperse the silver fine particles. By using the dispersant, the dispersion stability of the silver fine particles in the solvent can be improved. Here, the acid value of the dispersant is more preferably from 5 to 200, and it is particularly preferred that the dispersant has a functional group derived from phosphoric acid.

When the acid value of the dispersing agent is 5 or more, the amine is coordinated to the amine, and the surface of the particle starts to adsorb under the acid-base interaction with the metal substance which becomes alkaline; and the reason is that if it is 200 or less, It does not have a site of excessive adsorption, so it is adsorbed in a preferred form. Further, since the dispersing agent has a functional group derived from phosphoric acid, phosphorus P interacts with the metal M via oxygen O to be pulled, so that it is most effective for adsorption to a metal or a metal compound, and the amount of adsorption which can be minimized is necessary. To obtain better dispersion.

Further, as a polymer dispersant having an acid value of 5 to 200, for example, Lubrizol's SOLSPERSE series can be cited as SOLSPERSE-16000, 21000. , 41000, 41090, 43000, 44000, 46000, 54000, etc., BYK-Chemie's DISPERBYK series can be listed as: DISPERBYK-102,110, 111, 170, 190, 194N, 2015, 2090, 2096, etc., Evonik's TEGO Dispers series can be listed: 610, 610S, 630, 651, 655, 750W, 755W, etc. The Disparlon series manufactured by Nanben Chemical Co., Ltd. can be listed as DA-375, DA-1200, etc., and the Flowlen series manufactured by Kyori Chemical Industry Co., Ltd. can be exemplified: WK- 13E, G-700, G-900, GW-1500, GW-1640, WK-13E.

The content of the silver fine particle dispersion of the present embodiment in the case where the dispersant is contained may be adjusted according to characteristics required for viscosity or the like. For example, when the silver fine particle dispersion is used as a silver ink, it is preferred to use The content of the dispersant is 0.5% by mass to 20% by mass. When used as a silver paste, the content of the dispersant is preferably 0.1% by mass to 10% by mass.

The content of the polymer dispersant is preferably from 0.1% by mass to 15% by mass. When the content of the polymer dispersant is 0.1% or more, the dispersion stability of the obtained silver fine particle dispersion becomes good, and when the content is too large, the low-temperature sinterability is lowered. From the above viewpoint, the content of the polymer dispersant is preferably from 0.3% by mass to 10% by mass, particularly preferably from 0.5% by mass to 8% by mass.

In the dispersion of the present embodiment, the weight reduction rate when heated from room temperature to 200 ° C by thermal analysis is 20% by mass or less, and the weight reduction rate when heated from 200 ° C to 500 ° C is 10% by mass or less. . Here, the weight reduction rate up to 200 ° C mainly indicates the content of a short-chain amine which contributes to low-temperature sinterability, and the weight loss rate of a high-temperature component of 200 ° C to 500 ° C mainly indicates dispersion stability. The content of the acid valence dispersant. If the short-chain amine or the high-temperature component is excessive, the low-temperature sinterability is impaired. In other words, when the weight loss rate when heated from room temperature to 200 ° C is 20% by mass or less, and the weight loss rate when heated from 200 ° C to 500 ° C is 10% by mass or less, the low-temperature sintering property is further improved.

(E) Protecting Agent (Protective Dispersing Agent) The silver fine particle dispersion of the present embodiment may further contain an acid-valent dispersing agent (protective dispersing agent) as a protective agent added before silver fine particle synthesis. Here, the "protective dispersing agent" may be the same type as the "acidic dispersing agent" added after the silver fine particles are synthesized, or may be of different types.

(F) Other components In addition to the above-described components, the silver fine particle dispersion of the present embodiment may have an appropriate viscosity and adhesion in accordance with the purpose of use, without impairing the effects of the present invention. For example, an oligomer component, a resin component, an organic solvent (which can dissolve or disperse a part of a solid component), a surfactant, a tackifier or a surface, which functions as a binder, can be added to functions such as drying property or printability. Any component such as a tension adjuster. The optional component is not particularly limited.

Examples of the resin component include a polyester resin, a polyurethane resin such as a blocked isocyanate, a polyacrylate resin, a polypropylene phthalamide resin, a polyether resin, a melamine resin, or a decene. The resin component may be used alone or in combination of two or more.

Examples of the tackifier include clay minerals such as clay, bentonite, or hectorite, such as polyester latex resin, acrylic latex resin, and polyurethane latex. Latex such as resin or blocked isocyanate, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, cellulose derivative of hydroxypropyl methyl cellulose, xanthan gum Or a polysaccharide such as guar gum or the like, and these tackifiers may be used alone or in combination of two or more.

A surfactant different from the organic component may also be added. In the multicomponent solvent-based inorganic colloidal dispersion, the surface roughness of the coating layer and the shift of the solid content due to the difference in volatilization speed during drying tend to occur. By adding a surfactant to the silver fine particle dispersion of the present embodiment, the disadvantage is suppressed, and a silver fine particle dispersion capable of forming a uniform conductive coating layer can be obtained.

The surfactant which can be used in the present embodiment is not particularly limited, and any of an anionic surfactant, a cationic surfactant, and a nonionic surfactant can be used, and examples thereof include alkylbenzenesulfonate. Acid salt, quaternary ammonium salt, and the like. Among them, a fluorine-based surfactant and an anthrone-based surfactant are preferable because an effect is obtained with a small amount of addition.

(1-3-2) Silver fine particles The silver fine particles contained in the silver fine particle dispersion of the present embodiment have an alkoxy group having a partition coefficient logP of -1.0 to 1.4 and a carbon number of 5 or less adhered to at least a part of the surface. A silver fine particle of an amine.

By attaching an alkoxyamine having a partition coefficient logP of -1.0 to 1.4 and a carbon number of 5 or less to at least a part of the surface of the silver fine particles, silver fine particles can be imparted to a plurality of solvents (especially high-polarity solvents). Excellent dispersibility and low temperature sinterability.

As the solvent, a plurality of solvents can be used within a range that does not impair the effects of the present invention, and a solvent having a SP value (solubility parameter) of 7.0 to 15.0 can be used. Here, the silver fine particles uniformly dispersed in the highly polar solvent are one of the characteristics of the silver fine particle dispersion of the present invention, and in the present invention, since the compatibility with the short-chain amine having 5 or less carbon atoms is good, It is preferred to use an alcohol having 1 to 6 carbon atoms. Further, these solvents may be used singly or in combination of two or more.

Examples of the solvent having an SP value (dissolution parameter) of 7.0 to 15.0 include hexane (7.2), triethylamine (7.3), diethyl ether (7.7), n-octane (7.8), and cyclohexane (8.3). N-amyl acetate (8.3), isobutyl acetate (8.3), methyl isopropyl ketone (8.4), pentylbenzene (8.5), butyl acetate (8.5), carbon tetrachloride (8.6), ethyl Benzene (8.7), p-xylene (8.8), toluene (8.9), methyl propyl ketone (8.9), ethyl acetate (8.9), tetrahydrofuran (9.2), methyl ethyl ketone (9.3), chloroform (9.4 ), acetone (9.8), dioxane (10.1), pyridine (10.8), isobutanol (11.0), n-butanol (11.1), nitroethane (11.1), isopropanol (11.2), m. Phenol (11.4), acetonitrile (11.9), n-propanol (12.1), decyl alcohol (12.5), nitromethane (12.7), ethanol (12.8), cresol (13.3), ethylene glycol (14.2), methanol (14.8) ), phenol, p-cresol, propyl acetate, isopropyl acetate, tert-butanol, 1-pentanol, 2-pentanol, 4-methyl-2-pentanol, 3-methyl-1-pentyl Alcohol, 3-methyl-2-pentanol, 2-butyl , 1-hexanol, 2-hexanol, 2-pentanone, 2-heptanone, 2-(2-ethoxyethoxy)ethyl acetate, 2-butoxyethyl acetate, acetic acid 2- (2-Butoxyethoxy)ethyl ester, 2-methoxyethyl acetate, 2-hexyloxyethanol, and the like.

The particle diameter of the silver fine particles of the present embodiment is preferably a nanometer size at which a melting point is lowered, preferably from 1 nm to 200 nm, and may also include micron-sized particles as necessary.

Further, the conductive fine coating layer 6 may be formed by directly using the silver fine particle dispersion, but may be used by transfer to a conductive ink suitable for transfer printing to form a transfer printing on the resin layer 4. Conductive coating 6. Hereinafter, the conductive ink will be described.

The conductive ink for transfer printing of the present embodiment is characterized by comprising metal particles, a solvent containing ethanol, and a high boiling point solvent having a hydroxyl group in an amount of 0.1% by mass to 3.0% by mass. Further, a solid component containing a metal particle dispersion containing metal particles and an organic component (in other words, metal colloidal particles) as a main component and a dispersion medium in which the solid components are dispersed are contained. In the colloidal liquid, the "dispersion medium" may also dissolve a part of the solid component.

According to the metal colloidal liquid, since the organic component is contained, the dispersibility of the metal colloidal particles in the metal colloidal liquid can be improved. Therefore, even if the content of the metal component in the metal colloidal liquid is increased, the metal colloidal particles are hard to aggregate and can be maintained. Good dispersion stability. In addition, the term "dispersibility" as used herein means whether the dispersion state of the metal particles in the metal colloidal liquid is excellent (whether uniform) immediately after the preparation of the metal colloidal liquid, and the "dispersion stability" means that the metal colloidal liquid is adjusted. After a predetermined period of time, whether or not the dispersion state of the metal particles in the metal colloidal liquid is maintained is also referred to as "low sedimentation cohesiveness".

Here, in the metal colloidal liquid, the "organic component" in the metal colloidal particles is an organic substance that substantially constitutes metal colloidal particles together with the metal component. The organic component does not contain a trace amount of an organic substance which is initially contained as an impurity in the metal, an organic substance which adheres to the metal component in a trace amount of an organic substance mixed in a production process to be described later, a residual reducing agent which is not completely removed in the washing process, and a residual dispersant. Or a small amount of organic matter attached to a metal component. In addition, the term "minor amount" specifically means less than 1% by mass in the metal colloidal particles. Since the metal colloidal particles in the present embodiment contain an organic component, the dispersion stability in the metal colloidal liquid is high. Therefore, even if the content of the metal component in the metal colloidal liquid is increased, it is difficult for the metal colloidal particles to aggregate, and as a result, good dispersibility is ensured.

In addition, the "solid content" of the metal colloidal liquid in the present embodiment means that the dispersion medium is removed from the metal colloidal liquid using a cerium oxide gel or the like, for example, at a normal temperature (for example, 25 ° C) of 30 ° C or lower. The solid component remaining after drying for 24 hours usually contains metal particles, residual organic components, residual reducing agent, and the like. Furthermore, as a method of removing a dispersion medium from a metal colloidal liquid using a cerium oxide gel, various methods can be employed, for example, by coating a metal colloidal liquid on a glass substrate, a glass substrate with a coating film is added. The dispersion medium may be removed by placing it in a closed container having a cerium oxide gel for 24 hours or more.

In the metal colloidal liquid of the present embodiment, the concentration of the solid component is preferably from 1% by mass to 60% by mass. When the concentration of the solid component is 1% by mass or more, the content of the metal in the conductive ink for transfer printing can be ensured, and the conductive efficiency is not lowered. In addition, when the concentration of the solid component is 60% by mass or less, the viscosity of the metal colloidal liquid does not increase, the handling is easy, and industrially advantageous, a flat film can be formed. The concentration of the solid component is more preferably 5% by mass to 40% by mass.

The conductive ink for transfer printing is characterized by containing 0.1% by mass to 3.0% by mass of a high boiling point solvent having a hydroxyl group. The high boiling point solvent having a hydroxyl group is preferably selected from the group consisting of 1,3-butanediol (boiling point: 203 ° C), 2,4-diethyl-1,5-pentanediol (boiling point: 150 ° C / 5 mmHg, 1 In the case of air pressure of 200 ° C or more) or octanediol (boiling point: 243 ° C).

The "high boiling point solvent" means a solvent having a boiling point of 200 ° C or higher. In addition, since it has a moderate affinity for water by having a hydroxyl group, moisture in the air tends to be absorbed or adsorbed, and it tends to be moisturized. Therefore, an ink suitable for the transfer printing method can be produced with a small amount of addition. Further, by setting the amount of the high-boiling solvent to be minimized, the ink applied to the fluorenone coating can be semi-dried in a short period of time, and the printing cycle can be shortened.

The amount of the high boiling point solvent having a hydroxyl group is from 0.1% by mass to 3.0% by mass. When the amount is less than 0.1% by mass, the amount is too small, and it is difficult to obtain an ink shape suitable for the transfer printing method. When the amount is more than 3.0% by mass, the time to reach the semi-dry state suitable for the transfer printing method is prolonged, and the printing cycle is changed. Not good. Further, it is more likely to be an ink shape suitable for the transfer printing method, and it is possible to shorten the time to reach a semi-dry state suitable for the transfer printing method, and to have a high boiling point of a hydroxyl group from the viewpoint of the advantage of the printing cycle. The amount of the solvent added is particularly preferably from 0.3% by mass to 2.0% by mass.

Further, in the conductive ink for transfer printing, a highly volatile solvent such as ethanol is added in order to improve the drying property of the ink. By adding the solvent, the conductive ink for transfer printing can be quickly adjusted to a viscosity suitable for printing. As the highly volatile solvent, in addition to ethanol, a group selected from the group consisting of methanol, propanol, isopropanol, acetone, n-butanol, second butanol, and third butanol may be used in a group having a boiling point of less than 100 ° C. One or two or more low boiling solvents.

Further, in the conductive ink for transfer printing, a fluorine solvent such as hydrofluoroether is preferably contained. The fluorine solvent exhibits good wettability to the fluorenone coating due to low surface tension, and imparts good drying property due to relatively low boiling point. Among them, from the viewpoint of the ozone destruction coefficient, a hydrofluoroether is preferable to a fluorine solvent containing a halogen atom.

Further, the hydrofluorocarbon has an advantage of having a high polarity and having substantially no swelling of the fluorenone coating layer due to the ether bond, and exhibits good compatibility with an alcohol such as ethanol and dispersion in an alcohol. The compatibility of the metal particles in the film is also excellent, and therefore more preferable.

In the conductive ink for transfer printing, a fluorine-based surfactant having a fluorine atom may be added for the purpose of improving the wettability to the fluorenone coating. However, in this case, when the amount of addition is too large, the conductivity of the conductive coating layer produced by using the conductive ink for transfer printing is lowered, and if the amount added is too small, the effect of improving the wettability is insufficient. It is preferably 0.01% by mass to 2% by mass.

In the conductive ink for transfer printing, the surface tension is 22 mN/m or less. By sufficiently reducing the surface tension to 22 mN/m or less, the wettability of the conductive ink for transfer printing to the coating layer such as an fluorene resin can be sufficiently ensured. The surface tension is 22 mN/m or less, which can be achieved by adjusting the component ratio of the conductive ink for transfer printing of the present invention. The lower limit of the surface tension may be about 13 mN/m. Further, the so-called surface tension in the present invention is obtained by measuring the principle of a plate method (Wilhelmy method), for example, a fully automatic surface tension meter CBVP manufactured by Concord Interface Science Co., Ltd. -Z, etc. to measure.

(1-3-3) Method for producing silver fine particles and silver fine particle dispersions The method for producing silver fine particles and silver fine particle dispersions according to the present embodiment includes the steps of: generating silver fine particles; and adding and mixing the silver fine particles a step of dispersing the silver microparticles with an acid value dispersing agent; further comprising: a first pre-step of adjusting a silver compound which can be decomposed to form metallic silver by reduction, and a short chain having a partition coefficient logP of -1.0 to 1.4 And a second pre-step of producing silver fine particles having a short-chain amine having a carbon number of 5 or less adhered to at least a part of the surface by reducing the silver compound in the mixed solution.

In the first pre-step, it is preferred to add 2 mol or more of a short-chain amine to 1 mol of metallic silver. By setting the amount of the short-chain amine to 2 mol or more with respect to 1 mol of metallic silver, an appropriate amount of short-chain amine can be adhered to the surface of the silver fine particles produced by reduction, and the silver fine particles can be imparted to various types. Excellent dispersibility and low-temperature sinterability in a solvent (especially a highly polar solvent).

Further, according to the composition of the mixed liquid in the first pre-step and the reducing conditions (for example, the heating temperature and the heating time, etc.) in the second pre-step, it is preferred to set the particle size of the obtained silver fine particles. In order to produce a nanometer size at which the melting point is lowered, it is more preferably set to 1 nm to 200 nm. Here, micron-sized particles may also be included as needed.

The method of taking out the silver fine particles from the silver fine particle dispersion obtained in the second preceding step is not particularly limited, and examples thereof include a method of washing the silver fine particle dispersion and the like.

As a starting material for obtaining silver fine particles coated with an organic substance (a short-chain amine having a partition coefficient logP of -1.0 to 1.4), various known silver compounds (metal salts or hydrates thereof) can be used, and for example, silver nitrate can be cited. Silver salts such as silver sulfate, silver chloride, silver oxide, silver acetate, silver oxalate, silver formate, silver nitrite, silver chlorate, silver sulfide, and the like. The silver salt is not particularly limited as long as it can be reduced, and it can be dissolved in a suitable solvent or used in a state of being dispersed in a solvent. In addition, these may be used alone or in combination.

In addition, the method of reducing the silver compound in the raw material liquid is not particularly limited, and examples thereof include a method of irradiating light such as ultraviolet rays, an electron beam, ultrasonic waves, or thermal energy by a method using a reducing agent, and heating the method. Wait. Among them, from the viewpoint of easy handling, a method of using a reducing agent is preferred.

Examples of the reducing agent include amine compounds such as dimethylaminoethanol, methyldiethanolamine, triethanolamine, phenidone, and hydrazine; for example, sodium borohydride or hydrogen iodide. a hydrogen compound such as hydrogen; an oxide such as carbon monoxide or sulfurous acid; for example, ferrous sulfate, iron oxide, iron fumarate, iron lactate, iron oxalate, iron sulfide, tin acetate, tin chloride, tin diphosphate Low valence metal salts such as tin oxalate, tin oxide, tin sulfate; for example, ethylene glycol, glycerin, formaldehyde, hydroquinone, pyrogallol, tannin, tannic acid, salicylic acid, D- The sugar or the like is not particularly limited as long as it is soluble in the dispersion medium and the metal salt is reduced. In the case of using the reducing agent, light and/or heat may also be applied to promote the reduction reaction.

Specific examples of the method for preparing the silver fine particles coated with the organic material using the metal salt, the organic component, the solvent, and the reducing agent include a method in which the metal salt is dissolved in an organic solvent (for example, toluene or the like) to prepare a method. A metal salt solution is added to the metal salt solution as a short-chain amine as a dispersing agent or a protective dispersing agent having an acid value, and then a solution in which a reducing agent is dissolved is gradually added dropwise thereto.

In the dispersion containing silver fine particles coated with a short-chain amine or a protective dispersant having an acid value obtained in the above manner, in addition to the silver fine particles, there are also relative ions of the metal salt, residues or dispersion of the reducing agent. The agent tends to have a high electrolyte concentration or a high organic concentration in the entire solution. The solution in this state causes segregation of silver fine particles due to high conductivity and the like, and is easily precipitated. Alternatively, even if the precipitate is not precipitated, if the relative ions of the metal salt, the residue of the reducing agent, or the excess amount of the dispersing agent necessary for the dispersion remain, the conductivity may be deteriorated. Therefore, by washing the solution containing the silver fine particles to remove excess residue, the silver fine particles coated with the organic substance can be surely obtained.

As the washing method, for example, a dispersion containing silver fine particles coated with an organic component is allowed to stand for a predetermined period of time, and the generated supernatant is removed, and then a solvent (for example, water or methanol) for precipitating silver fine particles is added. Methanol/water mixed solvent, etc., and then stir the frame again, and then left to stand for a certain period of time, removing the generated supernatant, and repeating the above steps a plurality of times; performing centrifugation instead of the standing method; using super A method of performing desalination, such as a filter device or an ion exchange device. The silver fine particles coated with "short-chain amine or acid-valent dispersant" of the present embodiment can be obtained by removing excess residue by washing as described above and removing the organic solvent.

In the present embodiment, the metal colloidal dispersion is mixed with the silver fine particles coated with the short-chain amine or the acid-containing protective dispersant and the dispersion medium described in the above embodiment. obtain. The method of mixing the silver fine particles and the dispersion medium coated with the "short-chain amine or acid-protective dispersant" is not particularly limited, and can be carried out by a conventionally known method using a stirrer, a stirrer or the like. . Stirring can be performed using a spatula or an ultrasonic homogenizer of appropriate power.

In the case of obtaining a metal colloidal dispersion liquid containing a plurality of metals, the production method thereof is not particularly limited. For example, in the case of producing a metal colloidal dispersion liquid containing silver and another metal, the silver fine particles coated with the organic substance are described. In the preparation, the dispersion containing silver fine particles may be separately produced from the dispersion containing other metal particles, and then mixed, or the silver ion solution may be mixed with other metal ion solution and then reduced.

The silver microparticles can also be produced by the following steps: a first step of adjusting a silver compound which can be decomposed to form metallic silver by reduction, and a mixture of short-chain amines having a partition coefficient logP of -1.0 to 1.4; and a second step By reducing the silver compound in the mixed solution, silver fine particles having a short-chain amine having 5 or less carbon atoms are attached to at least a part of the surface.

For example, a complex compound formed by a metal compound such as silver oxalate containing silver and a short-chain amine can be heated to decompose a metal compound such as an oxalate ion contained in the complex. The atomic silver is agglomerated to produce silver fine particles protected by a protective film of a short-chain amine.

As described above, in the metal amine complex decomposition method in which amine-coated silver fine particles are produced by thermally decomposing a complex of a metal compound in the presence of an amine, metal amine as a single kind of molecule Since the decomposition reaction of the compound forms an atomic metal, the atomic metal can be uniformly formed in the reaction system, and the composition of the components constituting the reaction is unstable as compared with the case where the metal atom is formed by the reaction of a plurality of components. The resulting reaction unevenness is suppressed, especially when a large amount of silver fine particles are produced on an industrial scale.

Further, in the metal amine complex decomposition method, it is presumed that a short-chain amine molecule is coordinately bonded to the generated metal atom, and agglomeration occurs by the action of a short-chain amine molecule located on the metal atom. The movement of the metal atoms is controlled. As a result, according to the metal amine complex decomposition method, it is possible to produce silver fine particles having a very fine particle size and a narrow particle size distribution.

Further, on the surface of the produced silver microparticles, a plurality of short-chain amine molecules also generate a relatively weak force coordinate bond, and these dense silver oxide particles form a protective coating layer on the surface of the silver microparticles, thereby producing excellent storage stability. The surface is cleaned of coated silver particles. Further, the short-chain amine molecules forming the coating layer can be easily separated by heating or the like, so that silver fine particles which can be sintered at a very low temperature can be produced.

Further, when a solid metal compound is mixed with an amine to form a complex compound such as a complex compound, a short-chain amine having a carbon number of 5 or less is mixed with a dispersant having an acid value as a coating layer constituting the silver-coated fine particles. When it is used, the formation of a composite compound such as a complex compound becomes easy, and a composite compound can be produced by mixing for a short period of time. Further, by mixing the short-chain amine, it is possible to produce coated silver fine particles having characteristics corresponding to various uses.

The dispersion of the present embodiment obtained in the above-described manner can be directly used in the above state, and various inorganic components or organic components can be added without damaging the dispersion stability of the conductive ink, the conductive paste, and the low-temperature sinterability. .

(2) Method for Producing Conductive Coating Composite FIG. 2 is a process chart of a method for producing a conductive coating composite of the present invention. The method for producing a conductive coating composite of the present invention comprises: a first step (S01) of applying a resin onto at least a portion of the substrate 2 to form a resin layer 4; and a second step (S02) of dispersing the silver particles The body is applied to at least a portion of the resin layer 4; and in the third step (S03), the silver fine particles contained in the silver fine particle dispersion are sintered by external heating to form the conductive coating layer 6. Hereinafter, a case where the polyurethane resin layer is formed as the resin layer 4 will be described.

(2-1) Formation of Resin Layer (First Step (S01)) A step of forming a resin layer 4 by applying an aqueous polyurethane resin dissolved in a solvent to at least a part of the substrate 2. The film thickness of the resin layer 4 is preferably 1 μm or less. The film thickness can be appropriately controlled depending on the number of rotations of the spin coating, the amount of the diluent, and the like. Further, the polyurethane resin is preferably a water system dissolved in a solvent.

By using an elongation at break of 600% or more and having -COO-H, -COOR, -COO ^- NH ⁺ R ₂ and -COO ^- NH ₄ ⁺ (wherein R, R ₂ independently represent a straight chain or a branched An alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkylene group which may have a substituent, an oxyalkylene group which may have a substituent, an aryl group which may have a substituent, and an aromatic group which may have a substituent An aqueous polyamine group of any one of an alkyl group, a heterocyclic group which may have a substituent, an alkoxy group which may have a substituent, an alkoxycarbonyl group which may have a substituent, and a fluorenyl group which may have a substituent The formate resin can effectively improve the adhesion between the conductive coating layer 6 formed in the second step (S02) and the third step (S03) and the substrate 2, and can form conductivity having excellent conductivity. Coating 6.

For example, the aqueous polyurethane resin is applied onto the substrate 2 in a state of being dissolved in a solvent to form a resin layer 4. Usually, the aqueous polyurethane resin is present in a state of being dispersed in water (latex), and a solvent is volatilized to form a film. However, depending on the film formation conditions, the film is formed by the particle diameter of the latex. In particular, in the case where the thin resin layer 4 is to be formed, there is a problem that the surface roughness becomes large. On the other hand, by dissolving an aqueous polyurethane resin in a solvent (for example, ethanol or acetone), the latex is broken into a uniform solution, and thus film formation properties (especially film uniformity in a film) It is increased so that a good resin layer 4 can be formed.

Further, by using a polyurethane resin having an elongation at break of 600% or more in the adhesion layer (resin layer 4), in the third step (S03) of sintering the silver fine particles, the substrate 2 and the substrate 2 can be alleviated. The conductive coating 6 has a poor coefficient of thermal expansion. As a result, the sintering of the silver fine particles proceeds smoothly, whereby the conductive coating layer 6 having excellent conductivity can be obtained.

When the resin layer 4 is formed on the surface of the substrate 2, the surface treatment of the substrate 2 may be performed in order to improve the adhesion between the substrate 2 and the resin layer 4. Examples of the surface treatment method include a method of performing dry treatment such as corona treatment, plasma treatment, ultraviolet (UV) treatment, and electron beam treatment. The film formation method of the resin layer 4 is not particularly limited, and for example, immersion, spray type, bar coating type, spin coating, slit die coating type, air knife type, reverse roll coating type, gravure coating type, or the like can be used. In addition, the film formation temperature is not particularly limited, and a temperature equal to or higher than the minimum film formation temperature of the composition used as the raw material of the resin layer 4 may be used. Further, heat treatment may be performed at a temperature equal to or lower than the heat resistance temperature of the substrate 2 as needed.

(2-2) Coating of Silver Fine Particle Dispersion (Second Step (S02)) is a step of applying a silver fine particle dispersion onto the surface of the substrate 2. The silver fine particle dispersion is not particularly limited as long as the effect of the present invention is not impaired, and a plurality of conventionally known silver fine particle dispersions can be used. It is preferred to use a silver fine particle dispersion containing silver fine particles and having a carbon number of 5 or less. The short-chain amine, the highly polar solvent, and the acid-valent dispersant for dispersing the silver fine particles, and the short-chain amine has a partition coefficient logP of -1.0 to 1.4.

As a method of coating the silver fine particle dispersion, various methods such as self-immersion, screen printing, reverse printing, microcontact printing, spray type, bar coating type, spin coating type, ink jet type, and distribution can be used. The device type, the needle transfer method, the press method, the coating method using the bristles, the casting type, the flexographic type, the gravure type, the lithography method, the transfer method, the hydrophilic hydrophobic pattern method, or the syringe type are suitably selected and used.

When the conductive coating layer 6 is formed on the surface of the resin layer 4, the surface treatment of the resin layer 4 may be performed in order to improve the adhesion between the resin layer 4 and the conductive coating layer 6. Examples of the surface treatment method include a method of performing dry treatment such as corona treatment, plasma treatment, UV treatment, and electron beam treatment.

(2-3) Calcination of Silver Fine Particles (Third Step (S03)) The silver fine particles are sintered by heating the substrate 2 coated with the silver fine particle dispersion in the second step (S02) to form conductivity. The step of coating 6.

When the silver fine particle dispersion of the present embodiment is applied to the substrate 2, it can be heated and calcined at a relatively low temperature (for example, 300 ° C or lower, preferably 100 ° C to 250 ° C). The silver fine particles are sintered to obtain a conductive coating 6. When calcination is carried out, the temperature may be raised stepwise or the temperature may be lowered. Further, a surfactant, a surfactant, or the like may be applied in advance to the surface on which the silver fine particle dispersion is applied.

In the present embodiment, when the silver fine particle dispersion contains the binder component, the binder component is sintered in view of the strength of the coating film, etc., but it may be applied to various printing methods depending on the case. The viscosity of the silver fine particle dispersion is adjusted as the main purpose of the binder component, and the calcination conditions are controlled to remove all of the binder components.

The method of performing the heating and the calcination is not particularly limited. For example, the temperature of the silver fine particle dispersion applied or drawn on the substrate 2 is heated to 300 ° C or lower, for example, using a conventionally known oven or the like. Calcination, whereby sintering can be performed. The lower limit of the temperature of the heating and the calcination is not necessarily limited, and may be a temperature within a range that does not impair the effects of the present invention. Here, in the conductive coating layer 6 after the sintering, in terms of obtaining as high a strength as possible and excellent electrical conductivity, the residual amount of the organic substance is preferably small, but the effect of the present invention is not impaired. A part of the organic matter may remain in the range.

The representative embodiments of the present invention have been described above, but the present invention is not limited thereto, and various design changes can be made, and all such design changes are included in the technical scope of the present invention. Example

Hereinafter, the conductive coating composite of the present invention and the method for producing the same will be further described by way of examples and comparative examples, but the present invention is not limited to these examples.

<<Preparation Example 1>> 8.9 g of 3-methoxypropylamine (a reagent manufactured by Wako Pure Chemical Industries, Ltd., carbon number: 4, logP: -0.5), and 0.3 g of a polymer dispersant DISPERBYK-111 was mixed and thoroughly stirred by a magnetic stirrer to form an amine mixture (the molar ratio of the amine added was 10 relative to silver). Then, 3.0 g of silver oxalate was added while stirring. After the addition of the silver oxalate, the stirring was continued at room temperature, whereby the silver oxalate was changed to a viscous white substance, and the stirring was terminated when it was confirmed that the change was finished.

The obtained mixed liquid was transferred to an oil bath, and heated and stirred at 120 °C. Immediately after the start of the agitation, the reaction accompanying the generation of carbon dioxide starts, and then the stirring is performed until the generation of carbon dioxide is completed, whereby a suspension in which the silver fine particles are suspended in the amine mixture is obtained.

Then, in order to displace the dispersion medium of the suspension, 10 mL of a mixed solvent of methanol/water was added and stirred, and then the silver fine particles were precipitated and separated by centrifugation, and 10 mL of methanol was again added to the separated silver fine particles/ The mixed solvent of water is separated by centrifugation and centrifugation to precipitate silver fine particles, and 2.1 g of ethanol/isobutanol/isopropanol (Isopropyl alcohol, IPA) (40/40/30 v/v) is added. The solvent was used as a dispersion solvent, whereby silver fine particle dispersion A having a solid concentration of 48 wt% was obtained.

<<Preparation Example 2>> 8.9 g of 3-methoxypropylamine (a reagent manufactured by Wako Pure Chemical Industries, Ltd., carbon number: 4, logP: -0.5), and 0.3 g of a polymer dispersant DISPERBYK-102 was mixed and thoroughly stirred by a magnetic stirrer to form an amine mixture (the molar ratio of the added amine was 5 with respect to silver). Then, 3.0 g of silver oxalate was added while stirring. After the addition of the silver oxalate, the stirring was continued at room temperature, whereby the silver oxalate was changed to a viscous white substance, and the stirring was terminated when it was confirmed that the change was finished.

The obtained mixed liquid was transferred to an oil bath, and heated and stirred at 120 °C. Immediately after the start of the agitation, the reaction accompanying the generation of carbon dioxide starts, and then the stirring is performed until the generation of carbon dioxide is completed, whereby a suspension in which the silver fine particles are suspended in the amine mixture is obtained.

Then, in order to displace the dispersion medium of the suspension, 10 mL of a mixed solvent of methanol/water was added and stirred, and then the silver fine particles were precipitated and separated by centrifugation, and 10 mL of methanol was again added to the separated silver fine particles/ The mixed solvent of water was separated by centrifugation and centrifugation to precipitate silver fine particles, and ethanol containing 2.1 g of SOLSPERSE 41000 (manufactured by Lubrizol Co., Ltd.) was added. g, whereby silver fine particle dispersion B having a solid concentration of 48 wt% was obtained.

<<Preparation Example 3>> Into 50 mL of water which was made alkaline by adding 3 mL of a 10 N-NaOH aqueous solution, 17 g of trisodium citrate dihydrate and 0.36 g of tannic acid were dissolved. To the obtained solution, 3 mL of a 3.87 mol/L silver nitrate aqueous solution was added, and the mixture was stirred for 2 hours to obtain a silver colloid aqueous solution. The obtained silver colloid aqueous solution was dialyzed until the conductivity became 30 μS/cm or less, thereby performing desalting. After dialysis, concentration was carried out, and centrifugation was carried out at 2,100 rpm (920 G) for 10 minutes to remove coarse metal colloidal particles, thereby obtaining silver fine particle dispersion C having a solid concentration of 48 wt%.

<<Preparation Example 4>> 200 ml of toluene (a reagent manufactured by Wako Pure Chemical Industries Co., Ltd.) and 11 g of butylamine (a reagent manufactured by Wako Pure Chemical Industries, Ltd.), carbon number: 4, log P: 1.0 The mixture was mixed and thoroughly stirred by a magnetic stirrer (the molar ratio of the amine added was 2.5 with respect to silver). While stirring, 10 g of silver nitrate (a reagent grade manufactured by Toyo Chemical Industries Co., Ltd.) was added thereto, and after dissolving silver nitrate, 10 g of DISPERBYK-2090 as a polymer dispersant was added. 10 g of hexanoic acid (special grade of reagents manufactured by Wako Pure Chemical Industries Co., Ltd.). A 0.02 g/ml aqueous sodium borohydride solution prepared by adding 1 g of sodium borohydride (manufactured by Wako Pure Chemical Industries, Ltd.) to 50 ml of ion-exchanged water was added dropwise thereto to obtain a solution containing silver fine particles. After stirring for 1 hour, 200 ml of methanol (a special grade manufactured by Wako Pure Chemical Industries, Ltd.) was added to coagulate and precipitate the silver fine particles. Further, after the silver fine particles were completely sedimented by centrifugation, toluene and methanol as supernatants were removed, excess organic matter was removed, and 6 g of 2-pentanol was added to obtain silver fine particles having a solid concentration of 50 wt%. Dispersion D.

The silver fine particle dispersion A to the silver fine particle dispersion D and the other components shown in Table 1 were added and mixed to obtain conductive ink A to conductive ink D. Further, the amounts of the components shown in Table 1 are represented by % by weight. Further, the resin used for forming the resin layer into the ink is shown in Table 2.

[Table 1]

[Table 2]

<<Example 1>> A resin layer was formed to form an ink by diluting Hydran HW-312B manufactured by Dixon Co., Ltd. three times with ethanol. At this time, HW-312B was completely dissolved under visual conditions. The resin layer was formed into a film on a glass substrate at 2000 rpm for 30 seconds using a spin coater, and then heated at 120 ° C for 30 minutes to form a resin layer. Then, the conductive ink B was applied onto the fluorenone coating layer by a bar coater (No. 7), and the substrate with the resin layer was pressed against the coating layer to transfer the conductive coating layer thereon. On a substrate with a resin layer. Then, the conductive coating composite 1 was obtained by calcination at 120 ° C for 30 minutes.

<<Example 2>> A resin layer was formed to form an ink by diluting Hydran HW-311 manufactured by Dixon Co., Ltd. three times with N-methyl-2-pyrrolidone. At this time, HW-311 was completely dissolved under visual conditions. Otherwise, the conductive coating composite 2 was obtained in the same manner as in Example 1.

<<Example 3>> A conductive coating composite 3 was obtained in the same manner as in Example 1 except that the conductive ink C was used.

<<Example 4>> Epocros WS-700 manufactured by Nippon Shokubai was added to the resin layer of Example 2 to form an ink at a ratio of 5% by weight with respect to the resin layer forming ink. The conductive coating composite 4 was obtained in the same manner as in Example 2.

<<Example 5>> A conductive coating composite 5 was obtained in the same manner as in Example 1 except that the conductive ink D was used.

<<Example 6>> A super resin 420 manufactured by First Industrial Pharmaceutical Co., Ltd. was diluted three times with water to form a resin layer forming ink. The resin layer was formed into a film on a glass substrate at 2000 rpm for 30 seconds using a spin coater, and then heated at 120 ° C for 30 minutes to form a resin layer. Then, using the conductive ink A, the conductive coating composite 6 was obtained by the same method as in the first embodiment.

<<Example 7>> Essex (S-REC) BL-S manufactured by Sekisui Chemical Co., Ltd. was dissolved in an ethanol/toluene (=1/1 W/W) solution so that the solid content concentration became 10 wt%. A resin layer is formed to form an ink. Otherwise, the conductive coating composite 7 was obtained in the same manner as in Example 1.

(Example 8) Conductivity was obtained in the same manner as in Example 1 except that the Superflex 150HS manufactured by the First Industrial Pharmaceutical Co., Ltd. was diluted three times with water to form a resin layer-forming ink. Coating composite 8.

[Example 9] Conductivity was obtained in the same manner as in Example 1 except that Superflex 650 manufactured by Dai-ichi Pharmaceutical Co., Ltd. was diluted twice with water to form a resin layer-forming ink. Coating composite 9.

(Example 10) Conduction was carried out in the same manner as in Example 1 except that Hydran ADS-120 manufactured by DIC Corporation was diluted three times with water to form a resin layer-forming ink. Sex coating composite 10.

[Example 11] Hydrogen HW-312B manufactured by DIC was diluted 1.5 times with ethanol, and the film forming conditions of the spin coater were set to 1000 rpm and 30 sec. The conductive coating composite 11 was obtained in the same manner as in Example 1.

<<Comparative Example 1>> A resin layer was formed to form an ink by diluting Hydran HW-312B manufactured by DiCai (DIC) three times with water. The resin layer forming ink was applied onto a glass substrate using a bar coater No. 10, and a resin layer was formed, and then heated at 120 ° C for 30 minutes to form a resin layer. Then, the conductive ink A was applied onto the fluorenone coating layer by a bar coater (No. 7), and the substrate with the resin layer was pressed against the coating layer, whereby the conductive coating was transferred to the coating layer. On a substrate with a resin layer. Then, the comparative conductive coating composite 1 was obtained by performing calcination at 120 ° C for 30 minutes.

<<Comparative Example 2>> Superflex 470 manufactured by Daiichi Kogyo Co., Ltd. was formed into a resin layer using a bar coater No. 10, and then heated at 120 ° C for 30 minutes to form a resin. Floor. A comparative conductive coating composite 2 was obtained in the same manner as in Example 1 except the above.

Comparative Example 3 A comparative conductive coating composite 3 was obtained in the same manner as in Comparative Example 1, except that the ink was not formed using a resin layer.

Comparative Example 4 A comparative conductive coating composite 4 was obtained in the same manner as in Comparative Example 2, except that Superflex 210 manufactured by Daiichi Kogyo Co., Ltd. was used.

Comparative Example 5 A comparative conductive coating composite 5 was obtained in the same manner as in Comparative Example 4 except that the conductive ink C was used.

Comparative Example 6 A comparative conductive coating composite 6 was obtained in the same manner as in Comparative Example 1, except that the ink was formed using Aronmighty AS-60 manufactured by Toagosei Co., Ltd. as a resin layer.

Comparative Example 7 A comparative conductive coating composite 7 was obtained in the same manner as in Comparative Example 1, except that the bar coater No. 6 was used.

[Evaluation Test] (1) Measurement of Film Thickness of Resin Layer The resin layer was cut by a sharp blade such as a razor, and the difference in thickness between the glass substrate and the resin layer was measured by a confocal microscope (Keyence VK-X150). This measures the film thickness of the resin layer. The obtained values are shown in Table 3. (2) Evaluation of adhesion The tape (Michiban 18 mm) was attached to the conductive coating composite obtained in the examples and the comparative examples, and was peeled off at once to carry out the test. The case where the peeling was not observed when visually observed was ◎, and the case where only a very small portion (2% or less) was peeled off was observed as ○, and the case where only 10% or less of the area was peeled off was observed as Δ. The case where peeling of 20% or more was observed was set to ×, and the results are shown in Table 3. (3) Conductivity evaluation For the conductivity of the conductive coating composite, the surface resistance was measured using a Loreesta GP MCP-T610 manufactured by Mitsubishi Chemical Analytech Co., Ltd., and multiplied by the film. Thickness is used to calculate the volume resistance value. The volume resistance value was set to 20 μΩ·cm or less to ◎, 50 μΩ·cm or less was set to ○, and more than 50 μΩ·cm was set to ×, and the results are shown in Table 3. In addition, in the case where the adhesion evaluation was ○ or more and the conductivity evaluation was ○, the overall evaluation was ○, and the results are shown in Table 3. (4) Heat resistance evaluation The heat resistance of the conductive coating composite was evaluated. The glass relief is pressed against a coating on which various conductive inks are applied, and the non-image portion (unnecessary portion) is transferred and removed. Further, the pattern is transferred to the substrate by pressing the substrate with the resin layer on the cladding material. The pattern is set to a thin line, and the line width is set to 10 μm, 20 μm, 30 μm, 50 μm, 100 μm, and the length is set to 10 mm. Further, the conductive coating composite was obtained by firing at 120 ° C for 30 minutes. The thickness of the obtained conductive coating was about 0.3 μm. Then, the obtained conductive coating composite was subjected to high-temperature short-time exposure at 180 ° C for 1 minute for 5 times, and then the pattern shape was observed under a microscope. The case where deformation such as pattern bending or breakage was confirmed was ×, the case where almost no confirmation was confirmed was ○, and the case where it was not confirmed at all was ◎, and the result is shown in Table 3.

[table 3]

With regard to all of the conductive coating composites, it was confirmed that both the adhesion and the good conductivity were obtained. On the other hand, according to the comparison of the comparative conductive coating composite 3 and the implementation of the conductive coating composite, when the resin layer is not formed, good adhesion cannot be obtained.

In addition, as a result of the evaluation of the heat resistance of the conductive coating composite, it was found that the conductive coating composite can be provided with good heat resistance by setting the thickness of the resin layer to 1 μm or less.

1‧‧‧ Conductive coating composite

2‧‧‧Substrate

4‧‧‧ resin layer

6‧‧‧ Conductive coating

S01～S03‧‧‧Steps

Fig. 1 is a schematic cross-sectional view showing a conductive coating composite of the present invention. Fig. 2 is a flow chart showing a method of producing a conductive coating composite of the present invention.

Claims (11)

A conductive coating composite characterized by comprising: a substrate; a resin layer formed on at least a portion of the substrate; and a conductive coating formed on at least a portion of the resin layer, the conductive The coating layer is formed of silver fine particles, and the resin layer has a film thickness of 1 μm or less. The conductive coating composite according to claim 1, wherein a main component of the resin layer is a polyurethane resin, and an isocyanate group is added to the polyurethane resin. The terminal-protected polymer and/or the oxazoline group-containing polymer serves as a crosslinking agent. The conductive coating composite according to claim 2, wherein the crosslinking agent is contained in an amount of 10% by weight or less based on the solid content of the solid component of the polyurethane resin. The conductive coating composite according to any one of claims 1 to 3, wherein the conductive coating layer is formed of a silver fine particle dispersion, the silver fine particle dispersion comprising: Silver microparticles; short-chain amine; solvent; and dispersant for dispersing the silver microparticles. The conductive coating composite according to claim 4, wherein the short-chain amine has a carbon number of 5 or less. The conductive coating composite according to Item 4 or 5, wherein the solvent is a highly polar solvent. The conductive coating composite according to any one of claims 4 to 6, wherein the dispersing agent has an acid value. The conductive coating composite according to any one of claims 4 to 7, wherein the short-chain amine has a partition coefficient logP of from -1.0 to 1.4. The conductive coating composite according to any one of claims 4 to 8, wherein the short-chain amine is an alkoxyamine. A method for producing a conductive coating composite, comprising: a first step of applying a resin to at least a portion of a substrate to form a resin layer; and a second step of applying a silver fine particle dispersion to the At least a portion of the resin layer; and a third step of sintering the silver fine particles contained in the silver fine particle dispersion by external heating to form a conductive coating layer. The method for producing a conductive coating composite according to claim 10, wherein the thickness of the resin layer is 1 μm or less.