JP5608501B2 - Conductive pattern forming paste composition, conductive pattern and method for forming the same - Google Patents

Description

  The present invention relates to a conductive paste and a conductive pattern used for forming a conductive pattern such as an electrode of an electronic device, for example.

  As a method for forming a conductive pattern on a substrate using a conductive paste containing a conductive powder and an organic binder, a pattern forming method using a printing technique such as screen printing is widely used.

  The conductive pattern formed by such a pattern forming method can obtain good conductivity by, for example, baking this at a high temperature to thermally decompose the binder and to sinter the inorganic component.

  However, for example, it is difficult to apply to a flexible device such as electronic paper using a flexible substrate such as PET as a base material, or a device having low heat resistance such as a touch panel. Therefore, various conductive pastes capable of forming a conductive pattern by a low-temperature process at 250 ° C. or lower have been proposed (see, for example, Patent Document 1).

JP 2004-355933 A

In such a conductive paste, a conductive pattern having a specific resistance value on the order of 10 ⁻⁵ Ω · cm has been obtained so far by blending conductive powder using a highly conductive noble metal such as silver at a high concentration. Yes. On the other hand, a conductive pattern of the order of 10 ⁻² Ω · cm is obtained by using graphite as the conductive powder. However, an intermediate conductive pattern (on the order of 10 ⁻³ Ω · cm) has not been obtained.

Therefore, if the specific resistance value is controlled to the order of 10 ⁻³ Ω · cm by reducing the blending amount of the noble metal conductive powder, the variation of the specific resistance value due to the content of the conductive powder is large, and the slight content of Even if it fluctuates, the specific resistance value changes abruptly, causing a problem that it is difficult to stabilize the specific resistance value of the conductive pattern.

  Therefore, an object of the present invention is to provide a conductive paste capable of forming a conductive pattern that can stably obtain good electrical characteristics without using a high-temperature process.

In order to solve such a problem, the conductive paste of one embodiment of the present invention contains a conductive powder including silica core silver particles whose surfaces are coated with silver, an organic binder, and an organic solvent. It is characterized by that.
With such a configuration, it is possible to form a conductive pattern that can stably obtain good electrical characteristics without using a high-temperature process.

In the conductive paste of one embodiment of the present invention, the content of silver in the silica core silver particles is preferably 5 to 50% by mass. By containing silver in this range, it is possible to obtain good conductivity.
In the conductive paste of one embodiment of the present invention, the silica core silver particles are preferably surface-treated with a hydrophobic dispersant. By such surface treatment, the surface moisture content can be controlled and the dispersibility can be improved.

  Moreover, the formation method of the electrically conductive pattern of 1 aspect of this invention forms a coating film pattern using such an electrically conductive paste, and dries and / or hardens this coating film pattern at 80-200 degreeC. Is. By forming the conductive pattern in this way, it can be applied to a device having low heat resistance such as a flexible device.

  In addition, the conductive pattern of one embodiment of the present invention includes a conductive powder containing silica core silver particles whose surfaces are coated with silver, and an organic binder. With such a configuration, it is possible to obtain a conductive pattern having stable and good electrical characteristics.

  According to the conductive paste of one embodiment of the present invention, it is possible to form a pattern that has good printability and can obtain good electrical characteristics without using a high-temperature process.

It is a figure which shows the relationship between the content rate (weight ratio) and specific resistance value of the electrically conductive powder in an Example and a comparative example. It is a figure which shows the relationship between the content rate (volume ratio) and specific resistance value of the electrically conductive powder in an Example and a comparative example.

Hereinafter, the conductive paste of one embodiment of the present invention will be described.
The electrically conductive paste of this embodiment is characterized by containing the electrically conductive powder containing the silica core silver particle which coat | covered the surface of the silica particle with silver, the organic binder, and the organic solvent.

  The silica core silver particle used as the conductive powder in the conductive paste of the present embodiment is a particle obtained by coating the surface of the silica particle with silver, and is used for imparting conductivity in the formed conductive pattern.

  The silica core silver particles preferably have an average particle size of 1.0 to 20.0 μm. An average particle diameter is calculated | required by the average particle diameter of ten random conductive powders observed at 10,000 times using SEM (scanning electron microscope). When the average particle size is less than 0.5 μm, it becomes difficult for the conductive powders to come into contact with each other, and it becomes difficult to obtain sufficient conductivity. On the other hand, when the average particle size exceeds 20.0 μm, it becomes difficult to obtain a dense conductive pattern. More preferably, it is 1.0-10.0 micrometers.

  As the shape, various shapes such as a spherical shape, a flake shape, and a dentrite shape can be used. However, in consideration of dispersibility in the paste, a spherical shape having an aspect ratio of 1 to 1.5 is used. It is preferable.

  The silica particles that serve as the core are preferably spherical silica particles, and fused silica or nonporous materials obtained by surface-treating it can be used. Furthermore, the silica particle surface can be coat | covered by activating such a silica particle with palladium, for example, performing nickel plating, and then silver-plating.

  In such silica core silver particles, the silver content is preferably 5 to 50% by mass. If it is less than 5% by mass, it will be difficult to obtain good electrical resistance and other electrical characteristics, and if it exceeds 50% by mass, the cost will increase and the fluctuation in specific resistance due to the content can be suppressed. It becomes difficult. More preferably, it is 10-40 mass%.

As electrically conductive powder, things other than the silica core silver particle mentioned above may contain. Examples of such conductive powder include metals such as Ag, Au, Pt, Pd, Ni, Cu, Al, Sn, Pb, Zn, Fe, Ir, Os, Rh, W, Mo, Ru, and alloys containing these metals. Alternatively, a conductive oxide such as tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), or ITO (Indium Tin Oxide), conductive carbon, or the like can be used. Of these, Ag is particularly preferably used.

  The blending ratio of such conductive powder is preferably 70 to 90% by mass based on the nonvolatile content of the conductive paste (the component that does not volatilize from the paste by drying and remains in the film). If it is less than 70% by mass, it will be difficult to obtain sufficient electrical conductivity, while if it exceeds 90% by mass, it will be difficult to obtain fluidity of the paste and adhesion to the substrate. More preferably, it is 75-85 mass%.

  The organic binder resin in the conductive paste of the present embodiment imparts good printability and remains in the coating film even after the conductive paste is applied, dried and cured, and has good adhesion to the substrate of the conductive pattern. Used to obtain physical properties such as bending resistance and hardness.

  Examples of such organic binders include various modified polyester resins such as polyester resins, urethane-modified polyester resins, epoxy-modified polyester resins, and acrylic-modified polyester resins, polyether urethane resins, polycarbonate urethane resins, acrylic urethane resins, vinyl chloride, Vinyl acetate copolymer, epoxy resin, phenolic resin, acrylic resin, polyvinyl butyral resin, polyamideimide, polyimide, polyamide, nitrocellulose, cellulose acetate butyrate (CAB), modified cellulose such as cellulose acetate propionate (CAP) And the like.

In order to impart properties such as solvent resistance and high hardness to the formed pattern, a binder resin having a functional group (for example, a carboxyl group or a hydroxyl group) capable of three-dimensional crosslinking may be used. Among these, it is particularly preferable to include a carboxylic acid-containing resin containing at least two carboxyl groups in at least one molecule. Specific examples of such carboxylic acid-containing resins include, but are not limited to, the resins listed below.
(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid and one or more other compounds having an unsaturated double bond.
(2) Monofunctional epoxy such as butyl glycidyl ether or phenyl glycidyl ether in a copolymer of unsaturated carboxylic acid such as (meth) acrylic acid and one or more other compounds having unsaturated double bonds A carboxyl group-containing resin obtained by adding a compound.
(3) Copolymerization of a compound having an unsaturated double bond with an epoxy group such as glycidyl (meth) acrylate or 3,4-epoxycyclohexylmethyl (meth) acrylate, and a compound having an unsaturated double bond other than that A carboxyl group-containing resin obtained by reacting a saturated carboxylic acid such as propionic acid with a coalescence and reacting a polybasic acid anhydride with the generated secondary hydroxyl group.
(4) A compound having a hydroxyl group such as butyl alcohol is reacted with a copolymer of an acid anhydride having an unsaturated double bond such as maleic anhydride and a compound having an unsaturated double bond other than that. Obtained carboxyl group-containing resin.
(5) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy compound with a saturated monocarboxylic acid and reacting the resulting hydroxyl group with a saturated or unsaturated polybasic acid anhydride.
(6) A hydroxyl group- and carboxyl group-containing resin obtained by reacting a hydroxyl group-containing polymer such as a polyvinyl alcohol derivative with a saturated or unsaturated polybasic acid anhydride.
(7) Reaction of polyfunctional epoxy compound, saturated monocarboxylic acid, compound having at least one alcoholic hydroxyl group in one molecule and one reactive group other than alcoholic hydroxyl group that reacts with epoxy group A carboxyl group-containing resin obtained by reacting a product with a saturated or unsaturated polybasic acid anhydride.
(8) A saturated or unsaturated polybasic acid with respect to the primary hydroxyl group in the modified oxetane resin obtained by reacting a saturated monocarboxylic acid with a polyfunctional oxetane compound having at least two oxetane rings in one molecule. A carboxyl group-containing resin obtained by reacting an anhydride.
(9) After reacting a polyfunctional epoxy resin with a saturated monocarboxylic acid and then reacting with a polybasic acid anhydride, further react with a compound having one oxirane ring in the molecule. Carboxyl group-containing resin obtained by making it.

  Among these, it is particularly preferable to use the carboxyl group-containing resins (1), (2) and (3). With these, the molecular weight, glass transition point, and the like can be arbitrarily adjusted, and it is possible to appropriately adjust the printability of the conductive paste and the adhesion to the substrate.

  Moreover, it is preferable that the acid value of such carboxyl group-containing resin is 40-200 mgKOH / g. When the acid value of the carboxyl group-containing resin is less than 40 mgKOH / g, the cohesive force of the conductive paste is reduced, and transfer defects are likely to occur during printing. On the other hand, if it exceeds 200 mgKOH / g, the viscosity of the conductive paste becomes too high, and it becomes necessary to add a large amount of a crosslinking agent. More preferably, it is 45-150 mgKOH / g.

  In addition, when using a resin film for the substrate, polyester resin, acrylic resin, polyvinyl butyral resin, modified polyester resin, vinyl chloride / vinyl acetate copolymer, copolymer from the viewpoint of flex resistance and adhesion to the substrate A polyester resin or the like is preferable.

As the organic binder resin, a number average molecular weight (Mn) of 3000 to 50000 is suitable. If the number average molecular weight is less than 3000, the adhesion of the coating film is adversely affected, transfer defects during printing are likely to occur, and it becomes difficult to form a good conductive pattern. On the other hand, if the number average molecular weight exceeds 50000, whisker defects or line waviness due to stringing of the paste tends to occur during printing, and printability deteriorates. More preferably, it is 5000-30000.
The number average molecular weight is a standard polystyrene equivalent value measured by gel permeation chromatography (GPC).

  The organic solvent in the conductive paste of this embodiment is used for adjusting the viscosity and imparting good printability. Any organic solvent may be used as long as it can be dissolved without chemically reacting with the organic binder described above. Specifically, for example, toluene, xylene, ethyl acetate, butyl acetate, methanol, ethanol, isopropyl alcohol, isobutyl alcohol, 1-butanol, diacetone alcohol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, Examples include diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, terpineol, methyl ethyl ketone, carbitol, carbitol acetate, and butyl carbitol. These can be used alone or in combination of two or more.

  Further, for the purpose of preventing the drying of the paste in the printing process and maintaining the transferability, a high boiling point solvent having a boiling point at 1.013 MPa in the range of 240 to 330 ° C. may be used in combination.

Such high-boiling solvents include diamylbenzene (boiling point 260-280 ° C), triamylbenzene (boiling point 300-320 ° C), n-dodecanol (boiling point 255-259 ° C), diethylene glycol (boiling point 245 ° C), diethylene glycol. Monobutyl ether acetate (boiling point 247 ° C), diethylene glycol dibutyl ether (boiling point 255 ° C), diethylene glycol monoacetate (boiling point 250 ° C), triethylene glycol (boiling point 276 ° C), triethylene glycol monomethyl ether (boiling point 249 ° C), triethylene glycol Monoethyl ether (boiling point 256 ° C.), triethylene glycol monobutyl ether (boiling point 271 ° C.), tetraethylene glycol (boiling point 327 ° C.), tetraethylene glycol monobutyl Ether (boiling point 304 ° C.), tripropylene glycol (boiling point 267 ° C.), tripropylene glycol monomethyl ether (boiling point 243 ° C.), 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (boiling point 253 ° C.) Etc. Also, as petroleum-based hydrocarbons, AF Solvent No. 4 (boiling point 240-265 ° C.), No. 5 (boiling point = 275-306 ° C.), No. 6 (boiling point 296-317 ° C.), 7 No. (boiling point 259 to 282 ° C.), No. 0 solvent H (boiling point 245 to 265 ° C.) and the like may be included, and two or more of them may be included as necessary.
Such an organic solvent is appropriately contained so that the conductive paste has a viscosity suitable for printing.

  In the conductive paste of the present embodiment, it is preferable that the surface treatment is performed with a hydrophobic dispersant in order to improve the dispersibility by controlling the surface moisture content of the silica core silver particles. As such a hydrophobic dispersant, a fatty acid or a fatty acid salt can be used. Specific examples include benzotriazole, stearic acid, oleic acid, and salts thereof. When the silica core silver particles are formed by electroless silver plating, it is preferably added during electroless silver plating.

  Further, in the conductive paste of this embodiment, it is preferable to further contain a crosslinking agent in order to form a three-dimensional network chain structure and improve the solvent resistance and adhesion of the formed pattern.

  Any crosslinking agent may be used as long as it can react with the organic binder without deteriorating the properties and can be crosslinked. Such a crosslinking agent is not particularly limited as long as it is a resin that is cured by heating. For example, epoxy resin, phenol resin, melamine resin, alkyd resin, polyurethane resin, polyester resin, acrylic resin, polyimide resin, and their modification Examples thereof include resins, and these can be used alone or in combination of two or more. Other examples include oxetane compounds having at least two oxetanyl groups in the molecule.

  Among such crosslinking agents, it is preferable to include an epoxy resin containing at least two glycidyl groups in at least one molecule. Examples of such epoxy resins include bisphenol A type, hydrogenated bisphenol A type, bisphenol F type, bisphenol S type, phenol novolac type, cresol novolak type, bisphenol A novolak type, biphenol type, bixylenol type, and tris. Known epoxy resins such as phenol methane type, N-glycidyl type, N-glycidyl type epoxy resin, alicyclic epoxy resin, etc. are mentioned, but are not limited to specific ones. Alternatively, two or more kinds can be used in combination.

  The mixing ratio of these epoxy resins is suitably 1 to 100 parts by mass, preferably 5 to 40 parts by mass, per 100 parts by mass of the organic binder resin.

  Furthermore, you may mix | blend the curing catalyst for promoting reaction of organic binder resin and a crosslinking agent, for example, an amine compound, an imidazole derivative, etc.

  Moreover, in order to color the electrically conductive paste of this embodiment, a coloring agent can be contained. The type and shape of the colorant are not particularly limited, and known ones can be used. For example, when the colorant is used for a display, it may be a color suitable for causing a decrease in brightness sufficient to suppress external light reflection. Preferred examples include blue, black, and black by mixing three colors.

  In particular, black is preferable, and carbon black, solvent black, oil black, and the like can be used. However, carbon black for coloring material is suitable because of its availability. Examples of the carbon black include carbon black for color materials such as channel black, furnace black, and lamp black, and the above-described conductive carbon (black), acetylene black, and the like.

  The blending amount of such a colorant is not limited as long as the target brightness can be colored. From the viewpoint of printability, it is preferably 100 parts by mass or less with respect to 100 parts by mass of the organic binder resin. When the amount exceeds 100 parts by mass, problems such as a significant increase in viscosity and excessively high thixotropy occur. More preferably, it is 80 parts by mass or less.

Moreover, as a minimum, when it is set as a display use, for example, it is preferable to set it as 5 mass parts or more with respect to 100 mass parts of organic binder resin. When the blending amount of the colorant is less than 5 parts by mass, the brightness of the paste becomes high and the visibility of the display is deteriorated. More preferably, it is 10 parts by mass or more.
Such a colorant can be added as a powder or a dispersion.

  In addition, additives such as metal dispersant, thixotropy imparting agent, antifoaming agent, leveling agent, surface tension reducing agent, plasticizer, antioxidant, metal deactivator, coupling agent, filler, etc. Also good.

  In such a conductive paste, in order to obtain good printability, the concentration is preferably 50 to 1000 dPa · s as measured by a cone plate viscometer (25 ° C.). If it is less than 50 dPa · s, the ratio of the organic solvent in the paste is too large, the transferability is lowered, and it becomes difficult to perform good coating and printing. On the other hand, when it exceeds 1000 dPa · s, it is difficult to fill the plate, the scraping property with the doctor blade is deteriorated, and background stains (adhesion of paste to the non-image area) are likely to occur. More preferably, it is 100-650 dPa * s. In addition, you may dilute suitably so that it may become such density | concentration at the time of application | coating or printing.

  Moreover, it is preferable that the tack value which shows the dynamic adhesiveness of such an electrically conductive paste is 5-35. If the tack value is less than 5, the transferability at the time of printing is inferior, and the print quality may be deteriorated. On the other hand, when the tack value exceeds 35, picking of the printed material (breaking of the printed material) and jamming (the printed material clogs the printing machine) easily occur during printing. More preferably, it is 10-30. The tack value is a value measured using a rotary tack meter (generic name: incometer) under the conditions of 30 ° C. and 400 revolutions.

Using such a conductive paste, for example, a conductive pattern is formed as follows.
When using the printing method, the coating pattern of the conductive paste is formed on the substrate by printing. As the printing method, a known printing method such as screen printing, gravure printing, gravure offset printing, letterpress printing, pad printing can be used.

  At this time, as a base material, a flexible substrate such as a PET film can be used in addition to a printed wiring board and a glass substrate.

  After the coating film pattern thus formed on the substrate is dried at 60 to 120 ° C. for 1 to 60 minutes, the coating film pattern is cured by low-temperature baking at 100 to 250 ° C. for 1 to 60 minutes. A conductive pattern is formed.

  In this manner, a good pattern shape can be obtained, and a conductive pattern having low resistance and high solvent resistance can be obtained. Furthermore, since such a conductive pattern can be obtained without performing high-temperature baking, it can be used as an electrode of a flexible substrate or a device having low heat resistance.

  Hereinafter, the present embodiment will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. The following blending amounts are based on mass unless otherwise specified.

[Production Example of Silica Core Silver Plating Powder A]
(Palladium adhesion)
10 g of silica particles having an average particle size of 1.5 μm (Admafine SO-E5, manufactured by Admatechs) were etched and washed with water, and then added to 100 ml of a palladium-catalyzed solution containing 8% by weight of a palladium catalyst. Stir. The obtained particles were washed with water and then added to a 0.5% by weight dimethylamine borane solution adjusted to pH 6. In this way, silica particles activated with palladium were obtained.

(Plating pretreatment)
The resulting particles were stirred and dispersed in 300 ml of deionized water for 3 minutes. Then, 1 g of metallic nickel particle slurry (2020SUS (average particle size 200 nm), manufactured by Mitsui Kinzoku Co., Ltd.) was added to the dispersion over 3 minutes, and the nickel particles were adhered to the silica particles.

(Electroless nickel plating)
To the obtained particles, 500 ml of distilled water was added and sufficiently dispersed to obtain a suspension. While this suspension was stirred, nickel sulfate hexahydrate 50 g / l, sodium hypophosphite monohydrate 20 g / l, citric acid 50 g / l, and the pH was adjusted to 7.5. An electrolytic nickel plating solution was gradually added to perform electroless nickel plating on the silica particles. In this way, a nickel plating film was formed on the silica particles.

(Electroless silver plating)
To a solution obtained by dissolving 4.25 g of silver nitrate as a silver salt in 1180 ml of pure water at room temperature, 15 g of benzimidazole is added as a reducing agent and completely dissolved. 3.5 g of the product was dissolved. Then, 10 g of glyoxylic acid as a crystal adjusting agent was added and completely dissolved to prepare an electroless silver plating solution.

  Silica particles on which a nickel plating film was formed were put into the electroless silver plating solution thus prepared, and heated while stirring to keep the temperature at 70 ° C. to perform electroless silver plating. Furthermore, after washing the obtained particles with pure water, alcohol substitution was carried out, followed by drying in a vacuum dryer at 80 ° C. for 2 hours to obtain silica core silver particles having a silver adhesion amount of 30% by mass.

[Production Example of Silica Core Silver Plating Powder B]
Similarly to the silica core Ag plating powder A, after electroless silver plating, 0.4% by mass of oleic acid was added to the amount of silver in the plating solution. And after washing | cleaning the obtained particle | grains with a pure water, alcohol substitution was performed and it dried at 80 degreeC with the vacuum dryer for 2 hours, and obtained the silica core silver particle whose silver adhesion amount is 30 mass%.

[Preparation of conductive paste]
Each component was mix | blended with the compounding ratio shown in Table 1, and it kneaded with the 3 roll mill, and obtained the electrically conductive paste of Examples 1-3, Comparative Examples 1-5, and Reference Example 1 .

※１ ＢＬ−１、積水化学工業社製
※２ 平均粒径１．５μｍの球状銀粉
※３ ケッチェンブラックＥＣ−３００、ライオンアクゾ社製
※４ 平均粒径０．５μｍの球状シリカ粉

* 1 BL-1, manufactured by Sekisui Chemical Co., Ltd. * 2 Spherical silver powder with an average particle diameter of 1.5 μm * 3 Ketjen Black EC-300, manufactured by Lion Akzo * 4 Spherical silica powder with an average particle diameter of 0.5 μm

  The specific resistance value of each conductive paste thus obtained was evaluated. The evaluation method is as follows.

(Measurement of resistivity value)
After forming a 0.2 cm × 5 cm conductive pattern on a glass substrate and performing a heat treatment at 120 ° C. for 30 minutes, the resistance value is measured by a four-terminal method using a tester (manufactured by Hiki Corporation: Miliohm High Tester 3540). The specific resistance value was calculated based on the resistance and film thickness. Table 2 shows the measurement results of the specific resistance value.

Thus, it can be seen that specific resistance values on the order of 10 ⁻³ Ω · cm can be obtained in Examples and Reference Examples using silica core silver particles. Moreover, as shown in Examples 1 to 3 , dispersibility of the silica core silver particles in the conductive paste is improved and the specific resistance value is reduced by performing oleic acid treatment when the silver particles are plated with silver. You can see that

Furthermore, regarding Examples 1 to 3 and Comparative Examples 1 to 3 , the relationship between the content (weight ratio) of the conductive powder and the specific resistance value is shown in FIG.

As is clear from the results shown in FIG. 1, the conductive paste according to Examples 1 to 3 has a small change in specific resistance value even when the content of the conductive powder changes. On the other hand, it can be seen that the specific resistance values of the conductive pastes of Comparative Examples 1 to 3 change greatly with respect to the change in the content of the conductive powder.

Further, as Comparative Examples 6 to 7, conductive pastes having a silver powder content of 61.1% and 65.3% in volume ratio were prepared, and compared with Examples 1 to 3 and Comparative Examples 1 to 3 . . The relationship between the volume ratio of the conductive powder and the specific resistance value is shown in Table 3 and FIG.

As is clear from the results shown in FIG. 2, the conductive paste according to Examples 1 to 3 has a small change in resistance value even when the conductive powder content (volume ratio) changes. On the other hand, the specific resistance values of the conductive pastes of Comparative Examples 1 to 3 fluctuate greatly even with a slight volume change (for example, Comparative Examples 2 and 3). In order to suppress the rate of change of the specific resistance value, a large amount of conductive powder must be blended as in Comparative Examples 6 and 7, and the specific resistance value at that time is on the order of 10 ⁻⁵ Ω · cm. It becomes difficult to achieve the order of 10 ⁻³ Ω · cm.

Claims (4)

A conductive pattern forming paste composition comprising a conductive powder comprising silica core silver particles coated with silver on the surface of silica particles, an organic binder resin, and an organic solvent,
When the silica core silver particles are coated by electroless silver plating, the silica core silver particles are surface-treated with at least one hydrophobic dispersant selected from benzotriazole, stearic acid, and oleic acid added to the plating solution. A paste composition for forming a conductive pattern.   2. The conductive pattern forming paste composition according to claim 1, wherein a content of the silver in the silica core silver particles is 5 to 50 mass%. Using the paste composition according to claim 1 or 2, a coating film pattern is formed,
A method for forming a conductive pattern, comprising drying and / or curing the coating film pattern at 80 to 200 ° C. Conductive powder comprising silica core silver particles whose surfaces are coated with silver, and when the silica core silver particles are coated by electroless silver plating, benzotriazole, stearic acid added to the plating solution , A conductive pattern comprising a conductive powder surface-treated with at least one hydrophobic dispersant of oleic acid and an organic binder resin.

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