JP2003115216A - Conductive paste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide conductive paste having specific resistance and adhesion strength showing values equal to or almost comparable to those of an electrode formed of elemental Ag and improved in migration-resistance at a low cost. SOLUTION: The purpose is accomplished by conductive paste characterized by containing a binder resin, Ag powder and at least one kind of metal or compound of metal selected from a group comprising Ti, Ni, In, Sn and Sb.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive paste applicable to electrodes, conductive members, multilayer substrates, etc., and more particularly to a conductive paste having excellent migration resistance and improving the reliability of members using the electrodes.

[0002]

2. Description of the Related Art Conventionally, low resistance materials such as Ag, Cu and Al have been used as electrode materials used in electronic circuits and displays. However, Ag or Cu have a low resistance and can be used stably. Was limited to. Cu is often used in flexible circuits and TAB tape, but most of it is covered with a protective material to prevent the Cu surface from being oxidized or corroded, so be careful in surface protection and atmosphere control during processing. Requires. However, if Ag, Ag
Since it is stable in the air itself and various circuit patterns can be formed by firing in the air atmosphere, the degree of freedom of processing is very high. However, in any of Ag, Cu, and Al materials, migration due to moisture in the environment is likely to occur, and particularly in the case of Ag, Ag + ions eluted from the anode during voltage application may occur between electrodes or near the cathode. The only drawback remained was that it was deposited and eventually short-circuited. As a method for avoiding this problem, a device is usually provided to cover the electrode with a cured resin or the like so as not to come into contact with the outside air.

However, according to this method, there is a high possibility that migration will occur when a small gap such as a bubble or a crack exists between the resin and the electrode, and reliability cannot be ensured. In particular, in a precision circuit in which the distance between the electrodes is 500 μm or less, the insulation resistance between the electrodes becomes small, so that migration easily occurs and it is difficult to secure reliability.

In recent years, the size of circuits and the three-dimensional complication have progressed, and the number of cases in which conductive paste is applied and fired to form electrodes is increasing instead of sputtering or vapor deposition.

Therefore, Japanese Patent Laid-Open No. 10-27519 proposes a method for improving the migration resistance by using Ag / Pd alloy powder as a method for improving the electrode material. Further, in Japanese Patent Laid-Open No. 10-162646,
Ag / C as a method for improving migration resistance
A u alloy powder has been proposed.

[0006]

However, with Ag / Pd alloy powder and Ag / Cu alloy powder, the manufacturing process of these powders is complicated and the cost is high, and it is expensive to use as a material for general-purpose products. Further, since it is an alloy, there are many difficulties in controlling the particle shape, controlling the particle size distribution, and the like as compared with the production of powder of Ag alone, and the supply stability was lacking. In the migration resistance test of electrodes using these alloys, although the time to reach a short circuit is several times longer than that of electrodes using Ag alone, elution and reduction of Ag ions are not significantly suppressed, and It was not an effective measure.

Therefore, the present invention focuses on the above problems,
Another object of the present invention is to provide a method of further suppressing the elution and dissolution of Ag ions to further enhance the reliability of the electrode.

[0008]

In order to solve the above problems, the present invention has the following constitution. That is, the present invention is
Binder resin, Ag powder, and Ti, Ni, In,
It is a conductive paste containing at least one kind of metal or metal compound selected from the group consisting of Sn and Sb.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the conductive paste of the present invention will be described by taking a plasma display (hereinafter abbreviated as PDP) as an example, but the present invention is not limited thereto and other It can be used as an electrode member, a conductive member, a multilayer substrate, or the like.

The present invention is directed to a ceramic circuit board or PDP.
It is particularly preferably used as a material for forming an electrode by firing such as a glass substrate with an electrode and a material for curing a resin to form a conductive member such as a circuit of a printed circuit board or a connecting member of a TAB tape / electronic component. be able to.

Ag powder is essential in the conductive paste of the present invention. Generally, Ag powder is often used for the purpose of low resistance and low cost. The larger the amount of the Ag powder used, the more the spacing between the electrodes. The narrower the number, the more likely the short circuit defect due to migration of Ag is to occur, and therefore a countermeasure is required. Among them, the PDP, which is said to be a favorite of large-sized flat display panels in recent years, uses Ag for the entire surface or a part of a screen having a diagonal size of 30 to 60 inches, and the high definition is being promoted. It is very useful to use this conductive paste.

Conventionally, various methods of alloying Ag with a substrate have been proposed. In this case, however, the manufacturing process of Ag powder and the manufacturing process of alloy have to be changed, so that the Ag powder originally used is used. To control the same shape and particle size as
Many trials and errors are required, which leads to cost increase, which is not preferable. In the conductive paste of the present invention, migration is prevented by adding at least one kind of metal or a compound of at least one metal selected from the group of Ti, Ni, In, Sn, and Sb to Ag powder. be able to. More preferably, at least one metal or metal compound selected from the group consisting of Ni, In, and Sn is added. The types of metal compounds include oxides, sulfides, halides, hydroxides, acid chlorides, phosphates, nitrates, sulfates,
The carbonate, organic acid salt, organic metal compound, complex salt and the like are not particularly limited, but oxides that hardly generate by-products during firing are more preferable.

The preferred form of these metals or metal compounds is solid. Since it is solid, the conductive paste and the electrode layer have excellent stability over time, and the chemical change thereof is small even when fired, so that it can be preferably used. Further, in the case of a solid, a powder having a particle size of 30 μm or less is preferable. The thickness of the formed electrode is often 1 to 20 μm, and the particle size is preferably 30 μm or less, and more preferably 20 μm or less, in order to prevent uneven defects on the electrode.

Here, the preferred metal compound is
The oxide is obtained by baking an organometallic compound or a complex salt, but in that case, a liquid or a solution may be used as long as it can be baked in the air to sufficiently remove the organic component and be oxidized.

The valence of the metal used in this conductive paste
The case of an oxide will be described as an example. Metal alone
Has zero valence, but Ti, Ni, In, Sn, Sb
Is a compound, it takes various valences such as +1 valence and +2 valence.
obtain. In the present invention, the number of valences that can show a reducing action
Is preferred. Taking Sn as an example, Sn is a simple substance of Sn.
0 valence, SnO 2 valence, and SnO₂There are four-valued ones
However, 0-valent Sn and 2-valent SnO, which have a reducing effect, are more preferable.
It is used well. This is probably because Sn itself is oxidized
And Ag⁺Ag is reduced from the electrode by reducing ions.⁺of
It seems that the dissolution is suppressed. Therefore, the oxide
As an example, in the case of Ti, Ti, TiO, and Ti
₂O₃, Ni, Ni, NiO and Ni₃O_Four, In
In case ₂O and InO, Sb and Sb for Sb₂O₃
And SbO₂Can be more preferably used.

In addition, a conductive complex oxide such as indium tin oxide (hereinafter abbreviated as ITO) or a conductive oxide such as SnO ₂ in which a small amount of Sb or P is doped into Nesa has the same effect. Have. These oxides having good conductivity exists an empty orbital which allow electron transport, which indicates the reduction of the Ag ⁺ ions, Ag ⁺
It seems that the elution of ions is suppressed.

On the other hand, elements other than the above-mentioned metals cannot be used in the conductive paste of the present invention because they have insufficient migration resistance as compared with the above-mentioned metals. In particular, in the case of alkali metals and alkaline earth metals, on the contrary, the amount of ions eluted is large, which rather causes a problem of promoting migration. In addition, it cannot be used because the state of the metal is too stable to show a reducing action.

Ti, N contained in the conductive paste of the present invention
At least one metal or metal compound selected from the group consisting of i, In, Sn, and Sb is preferably 0.1 to 20 wt% of the metal / inorganic component of the electrode member. It is more preferably 0.5 to 3% by weight. Within this range, the migration resistance can be improved without impairing the conductivity of the Ag electrode.

Ti, N contained in the conductive paste of the present invention
The powder of the material containing at least one metal selected from the group of i, In, Sn, and Sb or the compound of the metal preferably has an average particle diameter of 0.01 to 30 μm. This is because the electrode pattern can be formed within this range without impairing the processing characteristics of the conductive paste.
A powder having a particle size smaller than 0.01 μm is not preferable because oxidation proceeds during firing and the migration resistance does not improve. On the other hand, when it is larger than 30 μm, the absolute amount of the number of powders of the material containing the metal or the compound of the metal present in the Ag electrode tends to decrease, and the migration resistance tends not to improve, and the addition amount increases. Even if it is dealt with, it is not preferable because protrusions increase on the electrode. In view of these characteristics, it is more preferable to use powder of 0.2 to 10 μm. Within this range, better dispersibility,
In addition, an electrode having more excellent migration resistance can be obtained. The average particle size referred to here is a particle size calculated by a laser diffraction / scattering method, a sedimentation method or the like by dispersing the particles in a dispersion medium such as water. In the present invention, a laser diffraction / scattering type device (MICROTRAC
-HRA Model; 9320-X100) was used to determine the average particle size. There is also a method of measuring the BET specific surface area and assigning it by the specific gravity of the particles to obtain the average particle size. Since the difference from the laser diffraction / scattering formula is about ± 0.5 μm, it is measured at particle sizes of 1 μm or more. The difference between the methods is considered to be small.

When the resin is cured to form the conductive layer, it is preferable to use flat conductive powder. Further, those having a particle size in the range of 5 to 30 μm can be used. The use of the flat powder increases the probability of contact between the conductive powders and reduces the specific resistance value. Particularly when forming an illegally conductive sheet, it is necessary to use a powder having a particle size corresponding to the thickness of the conductive layer. For example, when the thickness of the conductive layer is 10 μm, the average particle diameter is preferably within the range of 10 to 12 μm. In this way, an electrode having a desired specific resistance value with excellent migration resistance can be obtained.

The shape of the Ag powder may be granular (particulate), polyhedral or spherical. A in the coating
Since the g powder has a lower resistance when it is densely packed, it is more preferable that the g powder has a sharp particle size distribution, few agglomerates, and a spherical shape. In this case, the spherical shape means that the sphericity is 90 number% or more. The sphericity indicates the ratio of spherical particles obtained by photographing the powder with an optical microscope at a magnification of 300 times and counting the countable particles.
The higher the sphericity, the smaller the specific surface area and the larger the tap density, which is preferable.

An electrode formed on an insulating substrate such as a glass substrate or an alumina substrate using the conductive paste of the present invention is
The specific resistance value is preferably 1.6 to 20 μΩ · cm. The measurement of the specific resistance is calculated by measuring the resistance value of an electrode pattern having a predetermined line width and length, dividing the resistance value by the length and line width, and multiplying by the thickness. The lower the specific resistance, the better, and the specific resistance of Ag alone is 1.6μ.
The closer to Ω · cm the better. This is because the specific resistance of the electrode made of Ag alone is 2 to 5 μΩ · cm, and 10 to 4 times or less, that is, 20 μΩ · cm or less is practically preferable. If the specific resistance is larger than 20 μΩ · cm, heat generation during energization may increase or the driving voltage may increase, which is not preferable. More preferably, it is 2.5 to 15 μΩ · cm. More preferably, it is 2.6 to 10 μΩ · cm. Within this range, there is no need to change the conventional drive characteristics, and it can be preferably used. Further, by being in this range, the electrode has a thickness (preferably 0.1 to 30 μm, more preferably 1 to 10 μm) and a width (preferably 5 to 1000 μm).
.mu.m, more preferably 15 to 150 .mu.m) does not need to be large, so that the influence on the subsequent processing steps can be reduced.

There are various methods for forming electrodes, but in the case of forming electrodes by firing, in order to realize an electrode having the above-mentioned specific resistance, the particle size, tap density and specific surface area of Ag powder are not small. Are involved. That is, in the case of an Ag powder having a particle size distribution closer to that of monodispersion and having a good packing property, the probability of contact between the powders is high and a dense electrode can be obtained after firing, so that the specific resistance is low. At this time, the average particle diameter of the Ag powder is preferably 0.4 to 5 μm, more preferably 0.7 to 3 μm. Particle size is 0.
When it is less than 4 μm, the fluidity of the paste is deteriorated, and the printability, coating film forming property, and sheet forming property are deteriorated, which is not preferable. On the other hand, if the particle diameter exceeds 5 μm, the surface of the electrode pattern becomes rough and the pattern accuracy and thickness / dimensional accuracy of the thin film electrode having a thickness of 10 μm or less are reduced, which is not preferable. Furthermore, the specific surface area of the conductive powder is 0.3 to ^2.5 m ² / g.
It is preferable that the range is from the viewpoint of the accuracy of the electrode pattern. More preferably, the specific surface area is 0.35 to ² m ² / g. Furthermore, the tap density of Ag powder is 3 to 6 g / c.
It is preferably within the range of m ² . More preferably,
It is within the range of 3.5 to 5 g / cm ² . When the tap density is within this range, the binder resin component can be reduced as much as possible, the leveling property of the coating film is good, the shape retention of the coating film pattern is good, the pattern accuracy is improved, and the electrical conductivity is easily improved. Further, since the binder removal property is improved, the resistance value of the electrode obtained by firing is also reduced, which is preferable.

The electrode formed using the conductive paste of the present invention preferably has an adhesive strength with the substrate of 500 gf / mm ² or more. More preferably 700 gf / mm ²
That is all. If the adhesive strength is less than this, the electrode is likely to be peeled off at the contact point between the electrode and the external device or at the connecting portion with the electrode made of another material, resulting in poor reliability, which is not preferable. The adhesive strength is measured by forming a square electrode pattern of 1 mm square or 2 mm square on a glass substrate and baking it.
A copper wire is soldered to the pattern, the maximum adhesive force when the copper wire is pulled in the direction perpendicular to the substrate is measured, and the obtained force is assigned by the area of the electrode. A force gauge or the like can be used for the measurement. The electrode formed using the conductive paste of the present invention has an adhesive strength of 500 gf / m.
Since it is m ² or more, there is no fear of peeling when it is connected to an external device, and it can be preferably used for various circuit boards and displays.

In order to secure the above-mentioned adhesive strength, the Ag powder is sintered and the particles are fused together, and the fused A
It is necessary that the g powder be adhered to the substrate. Therefore, in order to improve the latter adhesive force, a method of adding a small amount of glass frit to the conductive paste can be preferably used.

When a glass frit is used, the glass transition temperature (Tg) and softening point (Ts) are 400 and 400, respectively.
It is preferable that the temperature is from 500 ° C to 450 ° C to 550 ° C.
Preferably Tg and Ts are 440 to 500, respectively.
C., 460 to 530.degree. Tg and Ts are 4 each
At temperatures below 00 ° C and 450 ° C, sintering of the glass begins before the photosensitive organic components such as polymers and monomers are evaporated,
This is because debinding is not successful and carbon residue may remain after firing to cause electrode peeling, which is not preferable for obtaining a dense and low-resistance electrode film. T
In the case of glass frit having g and Ts exceeding 500 ° C. and 550 ° C., respectively, when baked at a temperature of 600 ° C. or less, it may be difficult to obtain sufficient adhesive strength between the electrode film and the substrate and a dense electrode film.

In the present invention, as the composition of the glass frit, Bi ₂ O ₃ is preferably blended in the range of 30 to 70% by weight. If the amount is less than 30% by weight, the effect of controlling the glass transition point and the softening point and enhancing the adhesive strength of the conductor film to the substrate are small. If it exceeds 70% by weight, the softening point of the glass frit becomes low, and the glass frit melts before the binder in the paste evaporates. For this reason, the binder removal property of the paste is deteriorated, the sinterability of the electrode film is deteriorated, and the adhesive strength with the substrate tends to be decreased.

In particular, the glass frit is expressed in terms of oxide of Bi ₂ O ₃ 30 to 70% by weight SiO ₂ 5 to 30% by weight B ₂ O ₃ 6 to 20% by weight ZrO ₂ 3 to 10% by weight Al ₂ O ₃ It is preferable that the glass frit is an alkali-free glass frit containing 80% by weight or more of one having a composition range of 1 to 5% by weight and substantially not containing Na ₂ O, K ₂ O or Li ₂ O. Within this range, a glass frit capable of firmly baking the electrode film on the substrate at 550 to 600 ° C. which is a preferable baking temperature when using a glass substrate is obtained. The ratio of the glass frit contained in the electrode is preferably 0 to 10% by weight or less, more preferably 0.5 to 3%.
% By weight.

Here, as a method for forming a pattern of electrodes attached to the substrate with electrodes, it is preferable to use a conductive layer forming material such as the conductive paste of the present invention. Examples of such a method include a pattern printing method and a photosensitive paste method. Among them, a method of forming an electrode pattern using the photosensitive paste method is preferable.

The photosensitive paste method is a method in which a desired pattern is obtained by applying a photosensitive conductive paste on a substrate by screen printing, die coating application, green sheet transfer method, etc., and then irradiating with ultraviolet light and developing. is there. The present method can form a fine pattern with a small number of steps, and is therefore preferably used for applications such as electronic circuits.

The conductive paste having photosensitivity contains a photosensitive organic component as a binder resin, but may further contain glass frit and a diluting solvent. The photosensitive organic component is a negative type that photocures a desired pattern and develops and removes unnecessary portions, and a positive resin that solubilizes the binder resin in a developer by light irradiation and develops and removes the remainder to form a desired pattern. There are types. In the present invention, the photosensitive organic component may be a photosensitive conductive paste containing a photosensitive polymer or oligomer, a photosensitive monomer and a photopolymerization initiator.

In the present invention, it is preferable that the photosensitive conductive paste contains the photosensitive organic component in an amount of 5 to 30% by weight or more from the viewpoint of sensitivity to light.

The photosensitive organic component includes a photoinsolubilizing type and a photosolubilizing type. As the photoinsolubilizing type, (1) a functional group having at least one unsaturated group in the molecule. Containing a hydrophilic monomer, oligomer or polymer (2) containing a photosensitive compound such as an aromatic diazo compound, an aromatic azide compound or an organic halogen compound (3) a so-called diazo resin such as a condensation product of a diazo amine and formaldehyde There is something called.

As the photosolubilizing type, (4) a complex of a diazo compound with an inorganic salt or an organic acid, or a quinonediazo compound (5) a quinonediazo compound bound to a suitable polymer binder, For example, phenol, naphthoquinone 1, novolac resin 1, 2-diazide-5-sulfonic acid ester and the like can be used.

In the present invention, all of the above can be used, but from the viewpoint of easy handling and quality design, the above (1) is preferable, and a negative photosensitive conductive paste is obtained. You can

From the viewpoint of increasing the light transmittance of the photosensitive conductive paste, it is preferable that the refractive index of each component in the paste is close to each other, and the refractive index of the photosensitive organic component is close to that of the other components. Therefore, it is preferable to increase the refractive index of the photosensitive organic component. As a method for increasing the refractive index of the photosensitive organic component, it is effective to use a photosensitive monomer, a photosensitive oligomer or a photosensitive polymer having a high refractive index.

Specific examples of the photosensitive monomer having a functional group in the molecule (1) include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-
Butyl acrylate, iso-butyl acrylate, te
rt-butyl acrylate, n-pentyl acrylate, allyl acrylate, benzyl acrylate, butoxyethyl acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, 2-ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate. , Heptadecafluorodecyl acrylate, 2-hydroxyethyl acrylate, isobonyl acrylate, 2-hydroxypropyl acrylate, isodecyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafuro Pentyl acrylate, phenoxyethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, allylated cyclohexyl diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene Glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, Polypropy Glycol diacrylate, triglycerol diacrylate,
Examples include trimethylolpropane triacrylate, acrylamide, aminoethyl acrylate, and those in which the acrylate in the molecule of the above compound is partially or entirely changed to methacrylate, γ-methacryloxypropyltrimethoxysilane, and 1-vinyl-2-pyrrolidone. To be

Further, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, bisphenol A di (meth) acrylate, bisphenol A. -Di (meth) acrylate of ethylene oxide adduct, di (meth) acrylate of bisphenol A-propylene oxide adduct, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, thiophenol (meth) acrylate, benzyl Acrylates such as mercaptan (meth) acrylate, styrene, p-
Styrenes such as methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, chloromethylstyrene, and hydroxymethylstyrene, and chlorine or bromine atoms for some or all of the hydrogen atoms in these aromatic rings. Those substituted with iodine or fluorine, and those in which a part or all of the acrylate in the molecule of the above compound is changed to methacrylate, 1-vinyl-2
-Pyrrolidone and the like.

In the present invention, these may be used alone or in combination of two or more. In addition to these, the developability after exposure can be improved by adding an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid,
Examples thereof include crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

On the other hand, examples of (1) a photosensitive oligomer or polymer having a functional group in the molecule include side chains or molecular ends of an oligomer or polymer obtained by polymerizing at least one of the above monomers. It is possible to use a product having a functional group added thereto. It is preferable to contain at least alkyl acrylate or alkyl methacrylate, and more preferably to contain at least methyl methacrylate, because a polymer having good thermal decomposability can be obtained.

Preferred functional groups include those having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group include vinyl group, allyl group, acryl group and methacryl group.

The method of adding such a functional group to the oligomer or polymer is carried out by a method such as an ethylenically unsaturated compound having a glycidyl group or an isocyanate group or acrylic acid with respect to the mercapto group, amino group, hydroxyl group or carboxyl group in the polymer. There is a method of addition reaction with chloride, methacrylic acid chloride or allyl chloride.

Examples of the ethylenically unsaturated compound having a glycidyl group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, crotonic acid glycidyl ether, and isocrotonic acid glycidyl ether. .

Examples of the ethylenically unsaturated compound having an isocyanate group include (meth) acryloyl isocyanate and (meth) acryloyl ethyl isocyanate.

The ethylenically unsaturated compound having a glycidyl group or an isocyanate group, acrylic acid chloride, methacrylic acid chloride or allyl chloride is used in an amount of 0.05 to 0.05 with respect to the mercapto group, amino group, hydroxyl group or carboxyl group in the polymer. It is preferable to add 1 molar equivalent. In addition, the developability after exposure can be improved by copolymerizing an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinylacetic acid, and acid anhydrides thereof.

The acid value (AV) of the polymer or oligomer having an acidic group such as a carboxyl group on the side chain thus obtained is preferably 50 to 180, more preferably 70 to 140. If the acid value is less than 50, the development allowance becomes narrow. Further, if the acid value exceeds 180, the solubility of the unexposed area in the developing solution will decrease. Therefore, if the developing solution concentration is increased, peeling occurs even in the exposed area, and it is difficult to obtain a high-definition pattern.

Further, as a binder, non-photosensitive materials such as polyvinyl alcohol, polyvinyl butyral, methacrylic acid ester polymer, acrylic acid ester polymer, acrylic acid ester-methacrylic acid ester copolymer, α-methylstyrene polymer, and butyl methacrylate resin. It may also include a hydrophilic polymer.

It is preferable to use the photosensitive monomer in an amount of 0.05 to 10 times the total amount of the photosensitive oligomer and the polymer. The amount is more preferably 0.1 to 3 times.
If the amount exceeds 10 times, the viscosity of the paste will be reduced, and the dispersibility in the paste may be reduced. If the amount is less than 0.05 times, the solubility of the unexposed area in the developing solution tends to be poor.

In the photosensitive conductive paste, if necessary, a photopolymerization initiator, a sensitizer, a sensitization aid, a polymerization inhibitor, a plasticizer, a thickener, an organic solvent, an antioxidant, a dispersant, Additive components such as organic or inorganic suspending agents can be added.

As a specific example of the photopolymerization initiator,
Benzophenone, methyl o-benzoylbenzoate, 4,
4-bis (dimethylamine) benzophenone, 4,4-
Bis (diethylamino) benzophenone, α-amino
Acetophenone, 4,4-dichlorobenzophenone, 4
-Benzoyl-4-methyldiphenylketone, dibenzylketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p -T-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-
Chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyldimethylketanol, benzylmethoxyethyl acetal,
Benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzosuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6 -Bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadione-2- (o-methoxycarbonyl) oxime, 1-phenyl -Propanedion-2-
(O-Ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxime, Michler's ketone, 2 -Methyl- [4- (methylthio) phenyl]
-2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N
-Phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyldisulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenyl sulfone,
Examples include a combination of a photo-reducing dye such as benzoin peroxide, eosin, and methylene blue with a reducing agent such as ascorbic acid and triethanolamine. In the present invention, these may be used alone or in combination of two or more.

Further, the amount of the photopolymerization initiator is preferably 0.1 to 30% by weight, more preferably 2 to 20% by weight, based on the photosensitive organic component. If the amount of the photopolymerization initiator is too small, the photosensitivity becomes poor, and if the amount of the photopolymerization initiator is too large, the residual rate of the exposed area may be too small.

It is also preferable to add a sensitizer in order to improve the sensitivity. Specific examples of the sensitizer include 2,3-
Bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone, 2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, diethylthioxanthone, Michler's ketone , 4,4-bis (diethylamino) -benzophenone, 4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) chalcone, p-dimethylaminocinnamylideneindanone, p
-Dimethylaminobenzylidene indanone, 2- (p-
Dimethylaminophenylvinylene) -isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone, 1,3-carbonyl-bis (4-diethylaminobenzal) acetone, 3,3-carbonyl-bis (7
-Diethylaminocoumarin), N-phenyl-N-ethylethanolamine, N-phenylethanolamine,
Examples thereof include N-tolyldiethanolamine, N-phenylethanolamine, dimethylaminobenzoic acid isoamyl, diethylaminobenzoic acid isoamyl, 3-phenyl-5-benzoylthiotetrazole, 1-phenyl-5-ethoxycarbonylthiotetrazole, and the like. In the present invention, these may be used alone or in combination of two or more. Some sensitizers can also be used as photopolymerization initiators.

When the sensitizer is added to the photosensitive conductive paste, the amount added is 0.1 to 1 with respect to the photosensitive organic component.
It is 0% by weight, more preferably 0.2 to 5% by weight. If the amount of the sensitizer is too small, the effect of improving the photosensitivity is not exhibited, and if the amount of the sensitizer is too large, the residual ratio of the exposed area may be too small.

A thermal polymerization inhibitor may be added to the photosensitive conductive paste in order to improve the thermal stability during storage. Specific examples of the thermal polymerization inhibitor include hydroquinone and N-
Nitrosodiphenylamine, phenothiazine, pt-
Butylcatechol, N-phenylnaphthylamine, 2,
6-di-t-butyl-p-methylphenol, chloranil, pyrogallol and the like can be mentioned. When the thermal polymerization inhibitor is added, its addition amount is preferably 0.1 to 5% by weight in the photosensitive conductive paste, and more preferably,
It is 0.2 to 3% by weight. If the amount of the thermal polymerization inhibitor is too small, the effect of improving the thermal stability during storage will not be exhibited, and if the amount of the thermal polymerization inhibitor is too large, the residual rate of the exposed portion may be too small. is there.

As the plasticizer, for example, dibutyl phthalate (DBP), dioctyl phthalate (DOP), polyethylene glycol, glycerin, etc. can be added.

In the above-mentioned photosensitive paste method, line width /
Even when a fine pattern with a space width of less than 100 μm / 100 μm is formed, since the line edges are straight, there are no bumps or other protrusions, and the potential difference applied between adjacent electrodes is uniform at any location. Therefore, the chance of migration is reduced, and a more reliable electrode can be obtained.

In the present invention, the composition of the photosensitive type conductive paste is particularly preferably selected within the following range.

(A) Conductive powder: 70 to 99.9% by weight based on the sum of (a) and (b) (b) At least one selected from the group consisting of Ti, Ni, In, Sn, and Sb. Powder of metal or metal compound; 0.1 to 20% by weight with respect to the sum of (a) and (b) (c) Glass frit; 0 to 10% by weight with respect to the sum of (a) and (b) d) Photosensitive polymer and photosensitive monomer; 5 to 40% by weight based on the sum of (a) and (b) (e) Photopolymerization initiator; 2 to 30% by weight based on (d) (f) Solvent 5-40% by weight based on the sum of (a) and (b) (g) Additive; 0-20% by weight based on the sum of (a) and (b) Penetrates well,
The photo-curing function is sufficiently exhibited, the film strength of the exposed portion during development is increased, and an electrode pattern having a fine resolution can be formed. Further, the electrode film after firing has a low resistance and an increased adhesive strength, which is preferable.

The photosensitive conductive paste which can be preferably used in the present invention is, in addition to the above composition, a sensitizer, a photopolymerization accelerator, a plasticizer, a dispersant, a stabilizer, a thixotropic agent, an organic or inorganic precipitation inhibitor. It can be prepared by adding additives such as and mixing the slurry adjusted to have a predetermined composition uniformly with a stirrer such as a homogenizer and then uniformly dispersing it with a kneader such as a three-roller. .

On the other hand, in the pattern printing method, as a binder resin, a cellulosic compound represented by ethyl cellulose, methyl cellulose, etc., methyl methacrylate,
Acrylic compounds such as ethyl methacrylate, isobutyl methacrylate, methyl acrylate, ethyl acrylate and isobutyl acrylate can be used.

Further, additives such as a solvent and a plasticizer may be added to the paste. As the solvent, terpineol,
A general-purpose solvent such as butyrolactone, toluene, methyl cellosolve, and butyl carbitol acetate can be used. Further, as the plasticizer, dibutyl phthalate, diethyl phthalate or the like can be used. In this method, a paste passing portion is processed into a desired pattern shape on a screen plate in advance, the paste is pressed into the screen plate by a squeegee, and the paste is transferred to a substrate to form a pattern. Then, this pattern is fired to obtain an electrode, and this method is used for line width / space width = 10.
Limited to patterns of 0 μm / 100 μm or more. In the case of finer patterns than this, due to the limit of the fineness of the screen mesh, the line edges may have irregularities due to mesh marks, and even if a material with excellent migration resistance is used, migration will occur due to the bumps (protrusions). It is not preferable because it tends to occur. That is, with the electrode pattern having a line width / space width = 100 μm / 100 μm or more, the effect of the migration resistance of the conductive paste of the present invention can be exhibited even by the printing method, but when the pattern is finer than that, the photosensitive paste method is used. It is preferable to use.

An organic solvent may be added to the conductive paste of the present invention to adjust the viscosity. As the organic solvent used at this time, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone,
Examples thereof include isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, butyl carbitol, butyl carbitol acetate, butyl acetate and n-butanol. These organic solvents may be used alone or in combination of two or more.

The viscosity of the conductive paste includes conductive powder, organic solvent, composition / type of glass frit, plasticizer, thixotropic agent,
The amount is appropriately adjusted depending on the addition ratio of the suspending agent and the organic leveling agent, but the range is preferably 20 to 1000 poise.

In the present invention, the composition of the pattern printing type conductive paste is particularly preferably selected within the following range.

(A) Conductive powder: 70 to 99.9% by weight based on the sum of (a) and (b) (b) At least one selected from the group consisting of Ti, Ni, In, Sn and Sb Powder containing metal or metal compound; 0.1 to 20% by weight based on the sum of (a) and (b) (c) Glass frit; 1 to 4% by weight based on the sum of (a) and (b) % (H) Binder resin; 2 to 26% by weight based on the sum of (a) and (b) (i) Solvent; 0 to 60% by weight (j) based on the sum of (a) and (b) Agent: 0 to 20% by weight relative to the sum of (a) and (b) Within this range, the leveling property immediately after printing is good and it has suitable thixotropy, so that there is no pattern sag and the screen plate It is possible to obtain an electrode pattern according to the dimension. Further, the electrode film after firing has a low resistance and an increased adhesive strength, which is preferable.

The conductive paste for pattern printing used in the present invention has a predetermined composition by adding a plasticizer, a dispersant, a stabilizer, a thixotropic agent, and an organic or inorganic precipitation inhibitor in addition to the above composition. It can be produced by uniformly mixing the adjusted slurry with a stirrer such as a homogenizer and then uniformly dispersing it with a three-roller or a kneader.

Next, a method of manufacturing a PDP member for an electrode formed by using the conductive paste of the present invention will be described as a specific example. Although normal soda glass may be used for the substrate, "PD2" manufactured by Asahi Glass Co., Ltd., which is a heat-resistant glass for PDP, is used.
00 "or" PP8 "manufactured by Nippon Electric Glass Co., Ltd. can be used.

In the present invention, the surface treatment of the substrate can be carried out before applying the conductive paste onto the substrate in order to enhance the adhesion between the substrate and the coating film. As the surface treatment liquid, a silane coupling agent such as vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris- (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ
-(Methacryloxypropyl) trimethoxysilane, γ
(2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane or the like or an organic metal such as organic titanium, organic aluminum or organic zirconium. is there. A silane coupling agent or an organic metal diluted with an organic solvent such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol or butyl alcohol to a concentration of 0.1 to 5%. The surface treatment can be carried out by uniformly applying this on a substrate with a spinner or slit die coat and then drying at 80 to 140 ° C. for 10 to 60 minutes.

When a photosensitive resin is used as the binder resin, the conductive paste is printed on the entire surface of the glass substrate using a screen printing machine, and usually 10 to 70 ° C. at 10 to 100 ° C.
Heat and dry for 60 minutes to evaporate the solvents to a thickness of 5-2
A coating of 0 μm is obtained. Then, by a photolithography method, a film having an electrode pattern or a mask such as a chrome mask is used to irradiate and expose to ultraviolet rays to form a photo-cured portion as an electrode pattern, or a photo-solubilized portion is processed as a removed portion. You can Alternatively, a method of directly drawing with red or blue laser light or the like may be used without using a photomask.

As the exposure device, a stepper exposure device, a proximity exposure device or the like can be used. Also,
When exposing a large area, a photosensitive conductive paste is applied on a substrate such as a glass substrate and then exposed while being conveyed, so that an exposure device with a small exposure area can expose a large area. it can.

The active light source used at this time is, for example,
Visible rays, near-ultraviolet rays, ultraviolet rays, electron beams, X-rays and the like can be mentioned, and among these, ultraviolet rays are preferable, and as the light source thereof, for example, a low pressure mercury lamp, a high pressure mercury lamp, a halogen lamp, a germicidal lamp, etc. can be used. Among these, the ultra-high pressure mercury lamp is preferable. The exposure conditions vary depending on the thickness of the electrode film, but it is preferable to perform the exposure for 10 seconds to 10 minutes using an ultrahigh pressure mercury lamp with an output of 5 to 100 mW / cm ² .

Next, a portion which is not cured by the exposure is removed by using a developing solution to form a so-called negative type electrode pattern. Development is performed by a dipping method, a shower method, or a spray method. As a developing solution to be used, an organic solvent in which the photosensitive organic component can be dissolved can be used. Further, water may be added to the organic solvent within the range in which the dissolving power is not lost. For example, when a photosensitive organic component having a carboxyl group is present,
It can be developed with an aqueous alkaline solution. Although an aqueous solution of an alkali metal such as sodium hydroxide, an aqueous solution of sodium carbonate or sodium hydrogen carbonate, or barium hydroxide can be used as the alkaline aqueous solution, an organic alkaline aqueous solution is preferably used because the alkaline component can be easily removed during firing.

Specific examples of the organic alkali include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine,
Examples include diethanolamine. The concentration of the alkaline aqueous solution is preferably 0.05 to 2% by weight, more preferably 0.1 to 0.5% by weight. If the alkali concentration is too low, the unexposed area is not removed. If the alkali concentration is too high, the exposed area may be corroded, which is not good.

When a resin for pattern printing is used as the binder resin, the conductive paste is pattern-printed on a glass substrate by using a screen printing machine, and the pattern is printed at 70 to 100 ° C. for 10 minutes.
~ 60 minutes heating and drying to evaporate the solvent to a thickness of 5
A coating film of 20 μm can be obtained.

Next, the coating film is baked in air. Photosensitive organic components such as photosensitive polymers, photosensitive organic components such as photosensitive monomers and binders, photopolymerization initiators, sensitizers, sensitization aids, plasticizers, thickeners, organic solvents, dispersants and other added components Completely oxidize and evaporate the organic substances. The firing conditions are preferably firing at 550 to 600 ° C. for 5 minutes to 1 hour and baking on the substrate. Particularly at 500 ° C. or lower, the firing is insufficient, the denseness of the electrode film is lowered, the specific resistance is increased, and the adhesive strength with the substrate is lowered, which is not preferable. If the temperature exceeds 600 ° C., the glass substrate is thermally deformed, the flatness is deteriorated and the dimensions are changed, which is not preferable.

In the preparation, printing, exposure, and development steps of the photosensitive conductive paste, it is necessary to perform it at a place where ultraviolet rays can be blocked. Otherwise, the paste or coating film is photo-cured by ultraviolet rays, and the desired electrode film cannot be obtained.

When the conductive paste of the present invention is used, the thickness of the electrode film after firing is 1 to 10 μm and the minimum line width is 15
An electrode having a thickness of 80 μm, a pitch of 80 μm and an adhesive strength of 500 g / 1 mm ² or more can be easily produced, and can be preferably used as an electrode for a plasma display.

Next, both ends of the line end of the electrode are 10 mm.
All other parts are covered with a dielectric paste except for the above, a dielectric layer having a thickness of 5 to 30 μm is formed after firing, and stripe-shaped or lattice-shaped partition walls are fired to a height of 60 μm.
To 200 μm, and a thickness of 1 between the partition walls.
The phosphor layer is formed to have a thickness of 0 to 30 μm. The substrate was sealed with a PDP front plate and connected to a drive circuit by a flexible cable. Then, if the panel is lit for 1000 hours continuously in a room at room temperature of 40 ° C. and a humidity of 80% and the degree of migration of the electrodes is observed, a panel in which Ag precipitation is slightly seen in the electrodes at the connection portion due to elution / reduction of the electrode material, No matter where it is placed, it is possible to obtain a panel with no visible deposits. All the panels using the conductive paste of the present invention are excellent in migration property.

The migration resistance, which is the effect of the electrodes attached to the conductive paste of the present invention, can be evaluated in advance by preparing a model pattern and performing an acceleration test. Model pattern has line / space 600 / 600μ
m or 300/300 μm comb-shaped electrodes are formed on a glass substrate. The comb-shaped electrodes are provided so that the positive and negative electrodes alternate, and the positive and negative electrodes can be connected to a potentiometer, respectively. A glass fiber filter paper is placed on the substrate with this model pattern, placed in a constant temperature and humidity oven set to a predetermined temperature and humidity, a DC voltage of 1 to 100 V is applied, and a change in insulation resistance between adjacent electrodes is measured and evaluated. You can do it. At this time, in the material that causes migration, Ag repeatedly elutes / reduces in the space between the lines and deposits in a thin film branch shape, and eventually short-circuits when the growth continues. Therefore, the time required for the short-circuiting is measured and the sample is evaluated. Just go. In the case of 600/600 μm comb electrodes,
When the insulation resistance becomes 1 × 10 ⁶ Ω or less, it is short-circuited.

[0080]

EXAMPLES The present invention will now be described in more detail by way of examples. Example 1 The Ag powder used was a spherical one produced by a wet reduction method, having an average particle diameter of 2 μm, a specific surface area of 0.7 m ² / g and a tap density of 4.8 g / cm ³ .

As the metal or oxide exhibiting a reducing action, a commercially available reagent grade one having a particle size of 30 μm or less was used. Note that some metal powders having a small particle size may be ignited by being oxidized by air, so when these powders are used, they were prepared in a nitrogen atmosphere, mixed, and then worked in the atmosphere.

The glass frit is made of bismuth oxide (48.
1% by weight) silicon dioxide (27.5% by weight), boron oxide (14.2% by weight), zinc oxide (2.6% by weight), aluminum oxide (2.8% by weight), zirconium oxide (4.8%). Wt%) and the average particle size is 0.9
μm, glass transition point (Tg) 465 ° C., thermal softening point (T
s) having a temperature of 510 ° C. was used.

As the photosensitive resin, an acrylic copolymer having a carboxyl group and an ethylenically unsaturated group in its side chain, specifically, 40% methacrylic acid (MAA), 30% methyl methacrylate (MMA) and 30%. % Styrene (S
t) a copolymer having a carboxyl group (MAA), 0.4 equivalent (40%) of glycidyl methacrylate (GMA) was added and reacted, and trimethylolpropane tri was used as a photosensitive monomer. Acrylate was used.

As a photopolymerization initiator, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholino-1-propanone was used as an initiator, and the solvent was two components of γ-butyrolactone and butyl carbitol acetate. Was used.

In addition, amorphous silica Aerosil was used as an additive to stabilize the paste and prevent printing sag.

For each of the above components, 71% by weight of Ag powder, 1% by weight of TiO as an additive material, 1% by weight of glass frit, 10% by weight of photosensitive polymer, 4% by weight of photosensitive monomer, 10% by weight of γ-butyrolactone. , Butyl carbitol acetate 2% by weight and an additive 1% by weight were mixed and kneaded using a three-roller to obtain a conductive paste.

Next, a conductive paste was applied to the substrate with a screen printer. Commercially available soda lime glass (substrate thickness 1.3 mm) and high strain point glass "PD200" for plasma display (substrate thickness 2.8 mm) are used as glass substrates, and the alumina substrate is 100 mm square (thickness 1.1 mm).
I used the one. The small piece test was 100 mm square, and the panel test was 600 × 1000 mm. The conductive paste containing the photosensitive resin was printed on the entire surface of the substrate by using a polyester screen mesh, the solvent was dried under the condition of 100 ° C. for 10 minutes, and the pattern exposure was performed by an ultra-high pressure mercury lamp. A pattern was obtained by developing with a 2% aqueous sodium carbonate solution. In the case of the conductive paste for pattern printing, pattern printing is performed on the substrate by using a screen plate that has been subjected to a pattern processing for pre-removal, and after leveling for 10 minutes, 80 ° C.
The solvent was dried under the condition of 30 minutes to obtain a pattern. On the small piece substrate, a comb-shaped electrode for line / space = 300/300 μm and 600/600 μm for migration test, a pattern for resistance measurement, and a 1 mm square pattern for adhesive strength test were prepared. 600 for panel test
200/2 line / space on 1000mm substrate
A 00 μm stripe pattern was produced.

Regarding the conductive paste for pattern printing, 1% by weight of glass frit, 3% by weight of ethyl cellulose, butyl carbitol were added with 72% by weight of Ag powder and 1% by weight of a metal or its oxide exhibiting a reducing action as additive materials. A conductive paste was obtained by mixing at a compounding ratio of 24% by weight and kneading using a three-roller. Next, screen printing is performed using a stainless steel # 325 mesh that is patterned so that a desired pattern can be printed. Line / space for migration test = 600μ
An m / 600 μm comb-shaped electrode, a resistance measurement pattern, and a 1 mm square pattern for an adhesive strength test were prepared.

Next, the substrate was baked by holding it at 590 ° C. for 10 minutes in the atmosphere. Immediately after firing, a small piece was subjected to a migration test using a comb-shaped electrode, a specific resistance measurement, and an adhesive strength measurement. In the migration test, DC10V, 50V, or 100V was applied under the condition of 40 ° C. and 80% RT, and the time until a short circuit was measured, and it was confirmed that the electrode of Ag alone, which is a blank, lasts more than 20 times the time before the short circuit. I made it a goal.

On the substrate for panel test, a dielectric layer, a partition wall and a phosphor are formed on the electrodes, and the panel is bonded and sealed with the front plate and connected to a circuit to make the panel at 40 ° C. and 80% RT.
A life test was conducted under an atmosphere and with a voltage applied.

Examples 2-24 and Examples 26-31
Was performed in the same manner as in Example 1 except that the conditions of Example 1 were changed for the items shown in Table 1.

[0092]

[Table 1]

The conditions and results of the examples are shown in Table 1. In Examples 1 to 24 and Examples 26 to 31, the short circuit time was extended 20 times or more compared with the electrode formed of Ag powder alone. The effect of migration resistance could be obtained.
At this time, both the adhesive strength and the specific resistance were within the allowable range. Particularly, in Examples 26 to 31, Ni powder or ITO powder having various particle sizes is effective in preventing migration, 0.5 to 9 μm for Ni powder and 0.
The effect could be obtained in a very wide range of 2 to 3 μm. Furthermore, in Example 25, Ag electrodes containing 1% by weight of ITO were formed on the front plate and the back plate, and a dielectric layer and a MgO layer were formed on the electrodes of the front plate. A dielectric layer, a partition wall, and a phosphor layer were formed on the substrate, the front plate and the back plate were attached to each other, sealed in vacuum using a sealing frit, and then sealed with a rare gas to fabricate a panel.
When a DC drive circuit for migration evaluation was attached to the panel and evaluated, migration resistance of 1000 hours or more could be confirmed.

Comparative Examples 1 to 4 In Comparative Examples, a substrate on which electrodes were formed by using Ag powder as a conductive powder, a substrate on which electrodes were formed by using Ag / Pd alloy powder, and Ag / Cu alloy powder were used. The substrate on which the electrode was formed and the substrate on which the electrode was formed using Ag-coated Cu powder were evaluated. Other test conditions were evaluated in the same manner as in the example. The conditions and results are shown in Table 2. With the Ag powder, the specific resistance and the adhesive strength were secured, but the migration resistance was poor and a short circuit occurred in 1 hour. Furthermore, in Comparative Examples 2 and 3, the specific resistance value decreased and the short circuit time was only several times longer, resulting in an insufficient result. Comparative Example 4 was not very effective.

[0095]

[Table 2]

[0096]

The conductive paste of the present invention comprises a binder resin, Ag powder, and Ti, Ni, In, Sn, Sb.
Since it is decided to include at least one kind of metal or metal compound selected from the group, by forming an electrode using the paste, while maintaining the same specific resistance and adhesive strength as the conventional Ag electrode, It is possible to provide an electrode having excellent migration resistance.

The electrodes, conductive members, and multilayer substrates formed using the conductive paste of the present invention have the same or almost the same value as the specific resistance of electrodes made of Ag alone, and have migration resistance. The reliability can be improved at a low cost.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5E343 AA12 AA22 BB25 BB34 BB35                       BB44 BB59 BB72 DD03 ER33                       ER35 FF02 FF11 GG02 GG14                       GG20                 5G301 DA02 DA03 DA10 DA13 DA22                       DA23 DD01

Claims (8)

[Claims] 1. A binder resin, Ag powder, and Ti,
At least one selected from the group consisting of Ni, In, Sn, and Sb
A conductive paste containing a kind of metal or a compound of metal. 2. A binder resin, Ag powder, and Ni,
A conductive paste containing at least one metal or a compound of a metal selected from the group consisting of In and Sn. 3. The conductive paste according to claim 1, wherein the metal or metal compound is powder. 4. The conductive paste according to claim 1, wherein the metal compound is a metal oxide. 5. A conductive paste containing a binder resin, Ag powder, and Ni powder or ITO powder. 6. The Ni powder or the ITO powder has an average particle diameter of 0.01 to 30 μm.
The conductive paste according to. 7. The conductive paste according to claim 1, wherein the specific resistance of the electrode formed using the conductive paste is 1.6 to 20 μΩ · cm. 8. The conductive paste according to claim 1, wherein the adhesive strength between the electrode formed using the conductive paste and the substrate is 500 gf / mm ² or more.