JP2001351436A - Conductive paste composition and electronic components using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive paste composition fit as a forming material for an electrode circuit or the like requiring a high moisture resistance of an electronic component which has a good coating property and whose dry coating film is excellent in conductivity and anti-migration characteristics, and an electronic component using the same. SOLUTION: The conductive paste composition has as its indispensable ingredients (A) conductive powder, (B) thermoplastic resin, and (C) an organic solvent, and the conductive powder is a mixture of scale-like silver powder with average particle diameter of 0.5 μm to 12 μm and scale-like sliver-plated copper powder with average particle diameter of 0.5 μm to 12 μm, and the electronic component uses the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel conductive paste composition and an electronic component using the same. More specifically, the present invention relates to a conductive paste composition having excellent migration resistance and an electronic component having excellent moisture resistance reliability using the same.

[0002]

2. Description of the Related Art In the field of electronic components, it is common practice to paste a conductive substance such as a metal into a resin and form it into a paste, which is used for forming an electric circuit or an electrode. Silver is the most typical conductive substance among them. However, when a voltage is applied under high humidity conditions, silver is very easily ionized, and a silver migration phenomenon called migration is often observed. When migration occurs, a short circuit occurs between the electrodes, which causes a decrease in the moisture resistance reliability of the electronic component. In order to solve the above problems, studies have been made to add nickel powder, palladium powder, or copper powder instead of silver powder, and to add various additives. It is not a high sweeping measure. Further, when an electrode is formed by laminating several kinds of materials, there is a problem that the contact resistance increases when the conductive powder is a spherical powder or an atomized powder.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and shows good conductivity after paste application and drying, and stability under high temperature and high humidity. An object of the present invention is to provide a conductive paste composition excellent in migration resistance) and an electronic component using the same. That is, the present inventors have conducted various studies to solve the above problems, and as a result, using a mixed conductive powder of flaky silver powder and flaky silver-plated copper powder as the conductive powder to be used, coating and drying. The present inventors have found a conductive paste composition which is excellent in later conductivity and excellent in anti-migration properties, and have reached the present invention.

[0004]

The present invention provides a conductive paste composition comprising (A) a conductive powder, (B) a thermoplastic resin and (C) an organic solvent as essential components, wherein the conductive powder is The present invention relates to a conductive paste composition which is a mixed conductive powder of a flaky silver powder having an average particle size of 0.5 μm to 12 μm and a flaky silver-plated copper powder having an average particle size of 0.5 μm to 12 μm, and an electronic component using the same.

[0005]

Next, the conductive paste composition of the present invention and an electronic component using the same will be described in detail. As the conductive powder used in the present invention, flaky silver powder having an average particle size of 0.5 μm to 12 μm and an average particle size of 0.5
Mixed conductive powder of flaky silver-plated copper powder of μm to 12 μm, especially mixed conductive of flaky silver powder having an average particle size of 4 μm to 9 μm and flaky silver-plated copper powder having an average particle size of 4 μm to 9 μm Powders are preferred. When the average particle diameter of the silver powder and the silver-plated copper powder is less than 0.5 μm, aggregation of the conductive powder easily occurs in the paste, and when the average particle diameter is larger than 12 μm, it causes a non-uniformity of the formed coating film. Further, the difference between the average particle diameters of the silver powder and the silver-plated copper powder of the mixed conductive powder is preferably 8 μm or less, more preferably 4 μm or less. If the difference in the average particle size of the mixed conductive powder is larger than 8 μm, the conductive powder is separated in the paste, which causes a decrease in the stability of the paste and the characteristics of the formed coating film. The mixing ratio of the flaky silver powder and the silver-plated copper powder of the mixed conductive powder used in the present invention is such that the silver-plated copper powder is 1 to 100 parts by weight of the silver powder.
0 parts by weight to 235 parts by weight.
More preferably, the amount is 60 parts by weight to 150 parts by weight based on 00 parts by weight. If the mixing ratio of the silver-plated copper powder is less than 10 parts by weight with respect to 100 parts by weight of the silver powder, the migration resistance of the formed coating film tends to decrease if it exceeds 235 parts by weight. Further, the silver plating amount of the silver-plated copper powder used in the present invention is 0.5 to 100 parts by weight of the copper powder.
It is preferably from 20 to 20 parts by weight, more preferably from 1.5 to 5 parts by weight. The amount of silver plated copper powder is based on 100 parts by weight of copper powder.
If the amount is less than 0.5 part by weight, the conductivity is not sufficient, and if the amount is more than 20 parts by weight, the effect of the migration resistance tends to decrease.

As the thermoplastic resin of the present invention, there are acrylic resin, styrene resin, polyamide resin, polycarbonate resin, polyamideimide resin, polyetheramide resin and the like, but not particularly limited thereto.
A resin having an amide group, an ester group, an imide group or an ether group is preferable, and the thermoplastic resin is more preferably a resin having a repeating unit represented by the following general formula (I) or (II).

[0007]

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(Wherein R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom, X represents a chemical bond, —O—,

[0009]

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[0010] or

[0011]

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Wherein R ₅ and R ₆ each independently represent a hydrogen atom, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group. )

[0013]

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Or

[0015]

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Here, Ar is an aromatic divalent group represented by A
r 'represents an aromatic trivalent group.

[0017]

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(Wherein X is -O- or

[0019]

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Wherein R ₁₀ and R ₁₁ each independently represent a hydrogen atom, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group;
R ₇ , R ₈ and R ₉ each independently represent a lower alkyl group, a lower alkoxy group or a halogen atom;
y and z is 0 to 4 integer indicating the number of substituents, respectively, two X may be the same or different, R _7, R ₈
And when a plurality of R ₉ are bonded to each other, they may be the same or different.

The resin having the above repeating unit is produced by reacting an aromatic dicarboxylic acid, an aromatic tricarboxylic acid or a reactive acid derivative thereof with a diamine described below. The repeating unit represented by the above general formula (I) is, for example, 2,2-bis [4-
(4-aminophenoxy) phenyl] propane, 2,2
-Bis [3-methyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [3-methyl-4- ( 4-aminophenoxy) phenyl] butane,
2,2-bis [3,5-dimethyl-4- (4-aminophenoxy) phenyl] butane, 2,2-bis [3,5-
Dibromo-4- (4-aminophenoxy) phenyl] butane, 1,1,1,3,3,3-hexafluoro-2,
2-bis [3-methyl-4- (4-aminophenoxy)
Phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] cyclohexane, 1,1-bis [4- (4-aminophenoxy) phenyl] cyclopentane, bis [4- (4-aminophenoxy) ) Phenyl]
Sulfone, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy)
Phenyl] sulfone, 4,4'-carbonylbis (p
-Phenyleneoxy) dianiline, 4,4'-bis (4
It is preferable to use a diamine such as (-aminophenoxy) biphenyl. Among these, 2,2-bis [4- (4-aminophenoxy) phenyl] propane is particularly preferred. The repeating unit represented by the general formula (II) may be a diamine such as 1,3-bis (3-
Aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4 '-[1,3-phenylenebis (1-methylethylidene)] Bisaniline, 4,
It is produced using a diamine such as 4 '-[1,4-phenylenebis (1-methylethylidene)] bisaniline and 3,3'-[1,3-phenylenebis (1-methylethylidene)] bisaniline. In addition to the above reactive components, 4,4'-diaminodiphenyl ether, 4,4 '
-Diaminodiphenylmethane, 4,4'-diamino-
3,3 ', 5,5'-tetramethyldiphenyl ether, 4,4'-diamino-3,3', 5,5'-tetramethyldiphenylmethane, 4,4'-diamino-3,
3 ', 5,5'-tetraethyldiphenyl ether,
2,2 '-[4,4'-diamino-3,3', 5,5 '
-Tetramethyldiphenyl] propane, metaphenylenediamine, paraphenylenediamine, 3,3'-diaminodiphenylsulfone, piperazine, hexamethylenediamine, heptamethylenediamine, tetramethylenediamine, p-xylenediamine, m-xylenediamine, 3- Methylheptamethylenediamine, 1,3-bis (3-aminopropyl) tetramethyldisiloxane and the like can be used, and these can be used in combination.

The aromatic dicarboxylic acid is one having two carboxyl groups bonded to an aromatic ring, and the aromatic tricarboxylic acid is one having three carboxyl groups bonded to an aromatic ring and three carboxyl groups. Are preferably bonded to adjacent carbon atoms. Further, the aromatic ring may have a heteroatom introduced therein, or the aromatic rings may be bonded to each other via an alkylene group, oxygen or a carbonyl group. Further, a substituent which does not participate in the condensation reaction such as an alkoxy group, an allyloxy group, an alkylamino group, and a halogen may be introduced into the aromatic ring.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 4,4'-diphenyl dicarboxylic acid, 1,5-
Although naphthalenedicarboxylic acid and the like can be mentioned, terephthalic acid and isophthalic acid are preferred because they are easily available and inexpensive. The reactive derivative of the aromatic dicarboxylic acid means the above-mentioned aromatic dicarboxylic acid dihydride, dibromide, diester and the like. As aromatic tricarboxylic acids, trimellitic acid, 3,3 ′, 4-benzophenone tricarboxylic acid, 2,3,4′-diphenyltricarboxylic acid, 2,3,6-pyridine tricarboxylic acid,
3,4,4'-benzanilide tricarboxylic acid, 1,
Preferred are 4,5-naphthalenetricarboxylic acid, 2'-chlorobenzanilide-3,4,4'-tricarboxylic acid and the like. The reactive derivative of the aromatic tricarboxylic acid means an acid anhydride, a halide, an ester, an amide, an ammonium salt, or the like of the aromatic tricarboxylic acid.

The acid anhydrides of aromatic tricarboxylic acids include trimellitic anhydride, trimellitic anhydride monochloride, 1,4-dicarboxy-3-N, N-dimethylcarbamoylbenzene, 1,4-dicarboxylic acid Carbomethoxy-3-carboxybenzene, 1,4-dicarboxy-3
-Carbophenoxybenzene, 2,6-dicarboxy-
3-carbomethoxypyridine, 1,6-dicarboxy-
Preferred are 5-carbamoylnaphthalene, an ammonium salt of the above aromatic tricarboxylates and ammonia, dimethylamine, trimethylamine and the like. Of these, trimellitic anhydride and trimellitic anhydride monochloride are preferred because they are easily available and inexpensive.

In the present invention, an aromatic dicarboxylic acid,
Aromatic tricarboxylic acids or reactive derivatives thereof,
80 to 12 in total with respect to 100 mol% of diamine in total
It is preferably used in an amount of 0 mol%, more preferably 95 to 105 mol%. When the amount of the aromatic dicarboxylic acid, the aromatic tricarboxylic acid, or the reactive derivative thereof is less than 80 mol% or more than 120 mol% with respect to 100 mol% of the diamine, the molecular weight, mechanical strength, heat resistance and the like tend to decrease.

The organic solvent used in the present invention includes aromatic solvents such as benzene, toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; diethyl ether;
Ether solvents such as isopropyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether; ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, ethylene glycol monomethyl ether Acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl acetate Ruasetato, ester solvents such γ- butyrolactone; dimethylformamide, dimethylacetamide, amides solvents such as N- methylpyrrolidone. These solvents are used for dissolving the resin when preparing the paste or adjusting the viscosity of the paste. In preparing a paste, these organic solvents are used alone or in combination of two or more.

The amount of the organic solvent added is 100
It is preferably used in the range of 75 to 4600 parts by weight, more preferably 125 to 3060 parts by weight with respect to parts by weight. If the amount of the solvent is less than 75 parts by weight, the resin is difficult to dissolve, and if it exceeds 4600 parts by weight, the viscosity of the resin is remarkably reduced, and when a paste is used, the ability to form a coating film tends to be reduced. The conductive paste composition of the present invention comprises, for example, (A) 200 to 2400 parts by weight of a conductive powder,
(B) 100 parts by weight of thermoplastic resin and (C) solvent 75 to
It can be manufactured by mixing 4600 parts by weight and kneading and dispersing the mixture with a mill, a three-roll mill, a ball mill, a disper or the like.

In producing the conductive paste composition of the present invention, a dispersing agent or a coupling agent may be added to improve the dispersibility and coating property of the filler. As the dispersant, saturated fatty acids such as palmitic acid and stearic acid having 16 to 20 carbon atoms, and unsaturated fatty acids as
Oleic acid, linolenic acid and the like having 16 to 18 carbon atoms are used, and as these metal salts, salts with metals such as sodium, potassium, calcium, zinc and copper are used. The amount of these dispersants is usually 0.2 to 240 parts by weight, preferably 2 to 120 parts by weight, based on 100 parts by weight of the resin. If the amount of the dispersant is less than 0.2 parts by weight, the dispersibility of the conductive powder decreases, and if it exceeds 240 parts by weight, the conductivity of the coating film decreases, and the adhesion to the substrate decreases. Tend to.

As coupling agents, vinylmethoxysilane, vinyltriethoxysilane, vinyltris (β
-Methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β- (aminoethyl) Silane coupling agents such as -γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and titanate-based coupling agents; An aluminate-based coupling agent, a zirco-aluminate-based coupling agent, or the like can be used, and it is preferable to add it in an amount of 30 parts by weight or less based on 100 parts by weight of the thermoplastic resin. Electronic components using the conductive paste composition of the present invention include electrode materials such as aluminum electrolytic capacitors, tantalum solid electrolytic capacitors, and ceramic capacitors, conductive circuits formed on various substrates by screen printing, and ICs.
There is a conductive circuit forming part such as an antenna circuit formed in the card. The coating film formed from the conductive paste composition of the present invention has excellent migration resistance properties, and the electronic components used have features of high moisture resistance reliability.

[0030]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Synthesis example 1 equipped with thermometer, stirrer, nitrogen introduction pipe and cooling pipe
BAPP (2,2-bis [4- (4-aminophenoxy) phenyl] propane) as a diamine 100 g (0.2
4 mol) was dissolved in 400 g of N-methyl-2-pyrrolidone. The solution was cooled to −10 ° C. and at this temperature 49.5 g (0.24 mol) of isophthalic dichloride were added so that the temperature did not exceed −5 ° C. Thereafter, 56.6 g of propylene oxide was added, and stirring was continued at room temperature for 3 hours. The reaction solution was put into pure water to isolate the polymer. After drying, it was dissolved again in N-methyl-2-pyrrolidone, and this was poured into pure water to purify the polyamide polymer.

Example 1 To 100 parts by weight of the polyamide polymer obtained in the synthesis example, 1110 parts by weight of diethylene glycol dimethyl ether was added and dissolved, and varnish was dissolved in silver powder (product name: TC-20, manufactured by Tokuri Chemical Co., Ltd.).
V, TC-25A, TCG-7V, TCG-1, TCG
-5, TCG-131 and product name made by Degussa Japan
SF67, SF69, SF7, SF7A, SFR-Ag
And dry-classifying the mixture to adjust the average particle size to 9 μm and silver-plated copper powder (MA05K manufactured by Hitachi Chemical Co., Ltd. (silver plating amount: 2 parts by weight of silver with respect to 100 parts by weight of copper powder)). (Adjusted to 9 μm) in the proportions shown in Table 1 and dispersed with a disper for 30 minutes to obtain a paste. In addition, immediately after the dispersion, it was visually confirmed whether or not the filler was aggregated or separated. After defoaming the obtained composition, a predetermined amount of the paste was applied on a slide glass by a screen printing method (application area: 1 cm × 7.5 cm, application pressure: 40 ± 10 μm),
The coating was dried at 180 ° C. for 1 hour in a batch drying oven to obtain a dried coating film. The volume resistivity of the obtained dried coating film was measured with a double bridge resistance meter (manufactured by Yokogawa Electric Corporation). In addition, migration was measured using the dried coating film used for measuring the volume resistivity. The migration characteristics are as follows. An electrode with a spacing of 2 mm is formed in the center of the dried coating film, pure water is dropped so as to cover the entire electrode, and a voltage of 7 V is applied to both ends. Was measured. Table 2 shows the results of volume resistivity and migration characteristics. Next, a tantalum capacitor was prepared using this conductive paste composition as a cathode, and subjected to a humidity resistance test (PCT test: 121 ° C. under a saturated steam pressure of 2 atm.
After leaving for 8 hours, the number of test elements was 20), and the characteristics (capacitance; Cap, dielectric loss tangent; tan δ, equivalent series resistance; ESR, leakage current; LC) of the capacitor were measured. Table 2 shows the results.

Example 2 The procedure of Example 1 was repeated except that the average particle size of the silver powder used was adjusted to 0.5 μm, and the average particle size of the silver-plated copper powder was adjusted to 0.5 μm. Example 3 The same operation as in Example 1 was performed except that the adjustment of the average particle diameter of the used silver powder was 4 μm and the adjustment of the average particle diameter of the silver-plated copper powder was 4 μm. Example 4 Same as Example 1 except that the adjustment of the average particle size of the used silver powder was 12 μm and the adjustment of the average particle size of the silver-plated copper powder was 12 μm. Example 5 Example 5 was the same as Example 1 except that the adjustment of the average particle size of the used silver powder was 5 μm and the adjustment of the average particle size of the silver-plated copper powder was 9 μm.

Example 6 The procedure of Example 1 was repeated except that the average particle size of the silver powder used was adjusted to 4 μm and the average particle size of the silver-plated copper powder was adjusted to 12 μm. Example 7 Example 7 was the same as Example 1 except that the amount of silver of the silver-plated copper powder used was 0.5 part by weight of silver with respect to 100 parts by weight of copper powder. Example 8 The procedure of Example 1 was repeated except that the amount of silver of the silver-plated copper powder used was 20 parts by weight of silver with respect to 100 parts by weight of copper powder. Example 9 Example 9 was the same as Example 1 except that the mixing ratio of the conductive powder was 143 parts by weight of the silver-plated copper powder with respect to 1424 parts by weight of the silver powder. Example 10 The procedure of Example 1 was repeated except that the mixing ratio of the conductive powder was 468 parts by weight of silver powder and 1099 parts by weight of the silver-plated copper powder.

Comparative Example 1 The procedure of Example 1 was repeated except that the average particle size of the silver powder used was adjusted to 0.3 μm and the average particle size of the silver-plated copper powder was adjusted to 0.3 μm. Comparative Example 2 The procedure of Example 1 was repeated except that the average particle size of the silver powder used was adjusted to 15 μm and the average particle size of the silver-plated copper powder was adjusted to 15 μm. Comparative Example 3 The procedure of Example 1 was repeated except that the average particle size of the silver powder used was adjusted to 3 μm and the average particle size of the silver-plated copper powder was adjusted to 18 μm. Comparative Example 4 Silver-plated copper powder (product name: CuAg1 manufactured by Japan Energy Co., Ltd.)
0) was spherical, and the amount of silver was 10 parts by weight with respect to 100 parts by weight of copper powder. Comparative Example 5 A silver-plated copper powder (trade name A manufactured by Mitsui Kinzoku Mining Co., Ltd.) was used without using silver powder.
g coat Cu powder) is spherical.
Example 1 was repeated except that the amount of silver plating was 2 parts by weight and the amount of silver was 1566 parts by weight based on 100 parts by weight of copper powder.

COMPARATIVE EXAMPLE 6 Copper powder (trade name: MFP1300A, average particle size: 2 μm, manufactured by Mitsui Kinzoku Co., Ltd.) was used without using silver powder and silver-plated copper powder, and the compounding amount was 1
Except that the amount was 566 parts by weight, it was the same as in Example 1.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

The conductive paste composition according to the present invention comprises:
Having good coatability, the dried coating film has excellent conductivity,
Further, it is suitable as a material for forming an electrode circuit or the like of an electronic component, which is excellent in migration resistance and requires high moisture resistance reliability.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08L 79/08 C08L 79/08 Z 81/02 81/02 81/06 81/06 101/00 101/00 H01B 1 / 00 H01B 1/00 CJF term (reference) 4J002 CH071 CH091 CL001 CM041 CN011 CN031 DA076 DA077 EA058 ED028 EE038 EH158 EL058 EP018 EU028 FA016 FA017 FD116 FD117 FD208 GQ02 HA08 5G301 DA03 DA06 DA42 DD01

Claims (6)

[Claims] 1. A conductive paste composition comprising (A) a conductive powder, (B) a thermoplastic resin and (C) an organic solvent as essential components, wherein the conductive powder has an average particle size of 0.5 μm to 12 μm.
A conductive paste composition which is a mixed conductive powder of a flaky silver powder of μm and a flaky silver-plated copper powder having an average particle size of 0.5 μm to 12 μm. 2. The conductive paste composition according to claim 1, wherein the flaky silver-plated copper powder is present in an amount of 10 to 235 parts by weight based on 100 parts by weight of the flaky silver powder. 3. A silver plating amount of 0.1 part by weight per 100 parts by weight of copper powder.
3. The conductive paste composition according to claim 1, wherein the amount is 5 to 20 parts by weight. 4. The method according to claim 1, wherein the thermoplastic resin is an amide group, an ester group,
2. A resin having an imide group or an ether group.
4. The conductive paste composition according to item 2, or 3. 5. The thermoplastic resin having an amide group, an ester group, an imide group or an ether group is a resin having a repeating unit represented by the following general formula (I) or (II). Or the conductive paste composition according to 4. Embedded image (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom, and X represents a chemical bond, —O—, Or Wherein R ₅ and R ₆ each independently represent a hydrogen atom, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group. ) Or (In the formula, Ar represents an aromatic divalent group, and Ar ′ represents an aromatic trivalent group.) (Wherein X is -O- or Wherein R ₁₀ and R ₁₁ each independently represent a hydrogen atom, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group, and R ₇ , R ₈ and R
₉ each independently represents a lower alkyl group, a lower alkoxy group or a halogen atom, x, y and z are each an integer of 0 to 4 representing the number of substituents, and two Xs may be the same or different , R ₇ , R ₈ and R ₉ may be the same or different when a plurality of each are bonded) 6. An electronic component using the conductive paste composition according to claim 1, 2, 3, 4, or 5.