JP2010062018A - Conductive paste and electrode using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide conductive paste forming an electrode excellent in acid resistance. <P>SOLUTION: This conductive paste for a plasma display contains (A) an organic binder, (B) conductive powder having an average primary particle size of 0.5-1.4 μm, and (C) glass powder content of 0.1-0.9 wt.% inan inorganic component. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a conductive paste and an electrode using the same, and more particularly to a conductive paste useful for forming an electrode used for a front substrate or a rear substrate for a plasma display (hereinafter referred to as “PDP”), and using the same. Relates to the electrode formed.

  Generally, a rear substrate of a PDP partitions and forms an address electrode formed by patterning and firing on a glass substrate, a dielectric layer formed on the address electrode, and a discharge space formed on the dielectric layer. It is comprised from the rib etc. which do.

Of these members, a sandblasting method or an etching method is used for producing the rib.
The sand blasting method is a method of selectively cutting a portion other than the portion protected by the mask by spraying a cutting material or the like through a mask (protective film) from the rib glass layer. This method has a longer processing time than the etching method, and further has a problem of processing of the cutting material and processing of the cut glass powder.

On the other hand, the etching method is a method of selectively dissolving and removing portions other than those protected by the mask by etching the rib glass layer with an acid such as nitric acid through a mask (protective film). This method has a shorter processing time than the sand blast method, and there is no need for the processing of the cutting material and the processing of the cut glass powder as in the sand blast method.
However, the address electrode formed on the glass substrate has a structure in which a voltage is applied to the terminal portion, and neither a dielectric layer nor a rib is formed on the surface of the terminal portion. Therefore, the rib is formed using an etching method. In this case, it becomes an exposed state. For this reason, in this etching method, the exposed portion may be damaged by the acid of the etching process, causing disconnection or the like.
Therefore, as a method for forming the rib, a sand blast method that has a large number of work steps but does not affect the reliability of the electrode or the like is mainly used.

On the other hand, recently, a paste using lead-containing glass powder having acid resistance has been proposed as an electrode paste that can withstand even if a rib forming method by an etching method is employed (see Patent Document 1). ).
JP 2007-012371 A (Claims)

  The objective of this invention is providing the electrically conductive paste which can form the electrode excellent in acid resistance.

As a result of intensive studies to solve the above-mentioned problems, the inventors have completed an invention having the following contents.
That is, the PDP conductive paste of the present invention has an organic binder (A), a conductive powder (B) having an average primary particle size of 0.5 to 1.4 μm, and a content in the inorganic component of 0.1 to 0.00. The glass powder (C) that is 9 wt% is included.

  ADVANTAGE OF THE INVENTION According to this invention, the electrically conductive paste which can form the electrode excellent in acid resistance and excellent in adhesiveness can be provided. Thereby, the electrode for PDP suitable for the manufacturing method of the electrode including an acid treatment process is provided.

According to the inventors' research, it is presumed that the electrode is damaged by the acid by the following mechanism.
That is, when the rib is formed by the etching process, acid such as nitric acid penetrates into the exposed electrode and corrodes the glass between the electrode and the substrate, resulting in loss of adhesion to the substrate. It is presumed that the electrode is damaged by peeling off from the substrate.
In particular, it has been found that the larger the particle size of the conductive powder, the larger the gap between the conductive powders, and the greater the amount of acid entering the interior, resulting in significant electrode damage.
Therefore, as a method for solving such electrode damage, the inventors reduced the particle size of the conductive powder, reduced the glass amount as much as possible to increase the density of the conductive powder in the electrode, and infiltrated the acid into the electrode. Focused on preventing. However, when the particle size of the conductive powder is too fine, the resolution is deteriorated in the photo method, and when the amount of the glass powder is excessively reduced, there is a disadvantage that the adhesion with the substrate cannot be maintained.
Therefore, the inventors of the present invention have developed a glass powder for maintaining an excellent adhesion to the substrate and a range of the particle size of the conductive powder that effectively prevents acid penetration and also has excellent resolution during electrode pattern formation. The optimum blending amount was found and the present invention was conceived.

Each configuration of the present invention will be described below.
Examples of the organic binder (A) include a resin having a carboxyl group, specifically, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond and a carboxyl having no ethylenically unsaturated double bond. Any of the group-containing resins can be used. Examples of the resin (which may be either an oligomer or a polymer) that can be suitably used include the following.
(1) a carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid and a compound having an unsaturated double bond such as methyl (meth) acrylate,
(2) A copolymer of an unsaturated carboxylic acid such as (meth) acrylic acid and a compound having an unsaturated double bond such as methyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid chloride, etc. A carboxyl group-containing photosensitive resin obtained by adding an ethylenically unsaturated group as a pendant,
(3) A copolymer of an epoxy group such as glycidyl (meth) acrylate and an unsaturated double bond and a compound having an unsaturated double bond such as methyl (meth) acrylate, (meth) acrylic acid, etc. A carboxyl group-containing photosensitive resin obtained by reacting an unsaturated carboxylic acid of the product, and reacting a polybasic acid anhydride such as tetrahydrophthalic acid anhydride with the generated secondary hydroxyl group,
(4) To a copolymer of an acid anhydride having an unsaturated double bond such as maleic anhydride and a compound having an unsaturated double bond such as styrene, a hydroxyl group such as 2-hydroxyethyl (meth) acrylate and A carboxyl group-containing photosensitive resin obtained by reacting a compound having a saturated double bond,
(5) Carboxyl obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid such as (meth) acrylic acid and reacting the resulting secondary hydroxyl group with a polybasic acid anhydride such as tetrahydrophthalic anhydride. Group-containing photosensitive resin,
(6) An epoxy group of a copolymer of an unsaturated double bond such as methyl (meth) acrylate and a glycidyl (meth) acrylate has one carboxyl group in one molecule, and an ethylenically unsaturated bond A carboxyl group-containing resin obtained by reacting an organic acid not having a hydrogen atom and reacting a polybasic acid anhydride with the generated secondary hydroxyl group,
(7) a carboxyl group-containing resin obtained by reacting a polybasic acid anhydride with a hydroxyl group-containing polymer such as polyvinyl alcohol; and (8) a polybasic acid such as tetrahydrophthalic anhydride with a hydroxyl group-containing polymer such as polyvinyl alcohol. Examples of carboxyl group-containing resins obtained by reacting anhydrides include carboxyl group-containing photosensitive resins obtained by further reacting a compound having an unsaturated double bond with an epoxy group such as glycidyl (meth) acrylate, In particular, the resins (1), (2), (3), and (6) are preferably used.
In addition, in this specification, (meth) acrylate is a term that collectively refers to acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.

  The organic binder (carboxyl group-containing photosensitive resin or carboxyl group-containing resin) (A) may be used alone or in combination, but in any case, these are 10 to 50 parts by mass of the total amount of the composition. It is preferable to mix | blend in the ratio. When the blending amount of these polymers is less than the above range, the distribution of the resin in the film to be formed tends to be non-uniform, it is difficult to obtain sufficient photocurability and photocuring depth, and selective exposure and development. Makes patterning difficult. On the other hand, if the amount is more than the above range, it is not preferable because the electrodes are liable to be warped and the line width is shrunk during firing.

  The organic binder (A) has a weight average molecular weight of 1,000 to 100,000, preferably 5,000 to 70,000, and an acid value of 50 to 250 mgKOH / g. . Furthermore, when the organic binder (A) is a carboxyl group-containing photosensitive resin, those having a double bond equivalent of 350 to 2,000 g / equivalent, preferably 400 to 1,500 g / equivalent can be suitably used. . When the weight average molecular weight of the resin is less than 1,000, it adversely affects the adhesion of the film during development. On the other hand, when it exceeds 100,000, development failure tends to occur, which is not preferable. When the acid value is less than 50 mg KOH / g, the solubility in an alkaline aqueous solution is insufficient and the development is likely to be poor. On the other hand, when the acid value exceeds 250 mg KOH / g, the adhesion of the film is deteriorated during development or the photocured part ( This is not preferable because dissolution of the exposed portion) occurs. Furthermore, in the case of a carboxyl group-containing photosensitive resin, if the double bond equivalent of the photosensitive resin is less than 350 g / equivalent, a residue tends to remain during firing, whereas if it exceeds 2,000 g / equivalent, This is not preferable because the work margin is narrow and a high exposure amount is required during photocuring.

In the present invention, as an electrically conductive powder that effectively prevents acid penetration and has excellent resolution during electrode pattern formation, it has a mean primary particle size of 0.5 to 1.4 μm, more preferably 0.5 to 1.2 μm. Powder (B) is used.
Here, when the average primary particle size of the conductive powder is smaller than 0.5 μm, the light transmittance is deteriorated, and the resolution at the time of forming the electrode pattern is deteriorated. On the other hand, when the average primary particle size of the conductive powder is larger than 1.4 μm, the denseness of the conductive powder is deteriorated, and the acid is liable to penetrate into the electrode, resulting in remarkable damage. Further, the resistance value becomes high, which is not preferable.
The average primary particle size of the conductive powder in the present invention is an arbitrary selection of 50 conductive powders from a photograph of the conductive powder taken at 5,000 times with a scanning electron microscope (hereinafter referred to as “SEM”). The major axis is measured and the average value is calculated.
The conductive powder (B) is selected from the group consisting of Ag, Al, Pt, Au, Cu, Ni, In, Sn, Pb, Zn, Fe, Ir, Os, Rh, W, Mo, Ru. In addition to at least one metal, an alloy thereof, an oxide thereof, tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), ITO (Indium Tin Oxide), or the like can be used.
Various shapes such as a spherical shape, a flake shape, and a dendrite shape can be used as the shape of the conductive powder, but it is preferable to use a spherical shape in consideration of optical characteristics and dispersibility.
The blending amount of the conductive powder (B) is preferably 50 to 2,000 parts by mass per 100 parts by mass of the organic binder (A). When the blending amount of the conductive powder (B) is less than the above range, sufficient conductivity cannot be obtained, and when it is more than the above range, it becomes difficult to form a paste.

In this invention, in order to maintain the outstanding adhesiveness with a base material, the glass powder (content in an inorganic component is 0.1-0.9 wt%, More preferably, it is 0.3-0.8 wt%. C) is used.
Here, when the content of the glass powder in the inorganic component is less than 0.1 wt%, it becomes impossible to maintain the adhesion with the base material after firing, while the content of the glass powder in the inorganic component is 0.9 wt%. If it is more than%, the adhesion with the base material after acid treatment tends to deteriorate, which is not preferable.
As such glass powder (C), those containing lead oxide, bismuth oxide, zinc oxide, lithium oxide, or alkali borosilicate as a main component are suitably used. Particularly bismuth oxide, _Bi 2 _{O 3} 30 to 90 _wt%, B 2 _{O 3} 5 to 30 wt%, ZnO is 1 to 20 mass%, Si ₂ 0 to 20% by weight, BaO 0 to 35 What consists of a mass% composition range is suitable.
Further, the glass softening point of the glass powder (C) is preferably 420 to 580 ° C., the glass transition point is 360 to 500 ° C., and the thermal expansion coefficient α ₃₀₀ is preferably 60 × 10 ^{−7 to} 110 × 10 ⁻⁷ / ° C. .
About the particle size of this glass powder (C), it is preferable that they are a maximum particle size of 1.0-4.5 micrometers and an average particle diameter of 0.2-2.2 micrometers.

The conductive paste of the present invention can be used as a black conductive paste by further blending a black pigment (D) as necessary.
Since the black pigment (D) used in the present invention involves high-temperature firing at 500 to 600 ° C. in the electrode preparation process of the PDP, it is necessary to have stability such as color tone at high temperature, for example, ruthenium oxide Materials, ruthenium compounds, copper-chromium black composite oxides, copper-iron black composite oxides, cobalt oxides, and the like are preferably used. In particular, cobalt-based oxides such as tribasic cobalt oxide are optimal because they are extremely excellent in the stability and cost of the conductive paste.
Further, by using a slurry in which cobalt trioxide having a maximum particle size of 5 μm or less is uniformly dispersed in a solvent, a conductive paste free from secondary aggregates can be easily obtained.

Various shapes such as a spherical shape, a flake shape, and a dendrite shape can be used as the shape of the black pigment (D), but it is preferable to use a spherical shape in consideration of optical characteristics and dispersibility.
The blending amount of such a black pigment (D) is suitably 0.1 to 100 parts by weight, preferably 0.1 to 50 parts by weight per 100 parts by weight of the organic binder. The reason for this is that if the amount of the black pigment (D) is less than the above range, sufficient blackness cannot be obtained after firing. On the other hand, if the amount exceeds the above range, the light transmittance deteriorates. In addition, this is not preferable because of high costs.

In the conductive paste of the present invention, if necessary, a photopolymerizable monomer (E) and a photopolymerization initiator (F) can be blended in order to improve photocurability and developability.
Examples of such a photopolymerizable monomer (E) include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, polyurethane diacrylate, trimethylolpropane triacrylate. Acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane ethylene oxide modified triacrylate, trimethylolpropane propylene oxide modified triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate and each methacrylate corresponding to the above acrylate Phthalic acid, adipic acid, malein Mono-, di-, tri- or higher polyesters of polybasic acids such as itaconic acid, succinic acid, trimellitic acid, terephthalic acid and the like and hydroxyalkyl (meth) acrylates. It is not limited and these can be used alone or in combination of two or more. Among these photopolymerizable monomers, polyfunctional monomers having two or more acryloyl groups or methacryloyl groups in one molecule are preferable.

  The amount of such a photopolymerizable monomer (E) is suitably 20 to 100 parts by mass per 100 parts by mass of the organic binder (A). When the amount of the photopolymerizable monomer (E) is less than the above range, it is difficult to obtain sufficient photocurability of the composition. On the other hand, when the amount exceeds the above range, the amount is larger than the deep part of the film. Since photocuring of the surface portion is accelerated, uneven curing is likely to occur.

  Specific examples of such photopolymerization initiator (F) include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, Acetophenones such as 2,2-diethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl- 2-Dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-aminoacetophenones such as butanone; 2- Anthraquinones such as tilanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone, etc. Thioxanthones; ketones such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4 , 6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl-2,4,6-trimethylbenzoylphenylphosphine Phosphine oxide such as Fineito; various peroxides and the like can be used alone or in combination of two or more of these conventionally known photopolymerization initiator. The mixing ratio of these photopolymerization initiators (F) is suitably 0.3 to 30 parts by mass, preferably 1 to 20 parts by mass, per 100 parts by mass of the organic binder (A).

The photopolymerization initiator (F) is composed of N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, triethanolamine and the like. It can be used in combination with one or more of photosensitizers such as secondary amines.
If a deeper photocuring depth is required, titanocene photopolymerization initiators such as Irgacure 784 (manufactured by Ciba Specialty Chemicals) that initiate radical polymerization in the visible region, leuco dyes, etc. It can be used in combination as a curing aid.

In the conductive paste of the present invention, if necessary, in order to improve the storage stability of the composition, a compound having an effect such as complexation or salt formation with a metal or oxide powder as a component of the inorganic powder is stabilized. It can mix | blend as an agent (G).
Such stabilizers (G) include various inorganic acids such as nitric acid, sulfuric acid and hydrochloric acid; formic acid, acetic acid, acetoacetic acid, citric acid, stearic acid, maleic acid, fumaric acid, phthalic acid, benzenesulfonic acid, sulfamic acid Various organic acids such as phosphoric acid, phosphorous acid, hypophosphorous acid, methyl phosphate, ethyl phosphate, butyl phosphate, phenyl phosphate, ethyl phosphite, diphenyl phosphite, mono (2-methacryloyloxy) Examples include acids such as various phosphoric acid compounds (inorganic phosphoric acid, organic phosphoric acid) such as ethyl) acid phosphate and di (2-methacryloyloxyethyl) acid phosphate, and these can be used alone or in combination of two or more. .
Such a stabilizer (G) is preferably blended at a ratio of 0.1 to 10 parts by mass per 100 parts by mass of the inorganic powder.

  Further, if necessary, other additives such as a defoaming / leveling agent such as silicone and acrylic, and a silane coupling agent for improving the adhesion of the film can be blended. Further, if necessary, a known and usual antioxidant and a thermal polymerization inhibitor for improving the thermal stability during storage can be blended.

Next, a method for forming an electrode using the conductive paste of the present invention will be described.
The conductive paste of the present invention may be laminated on a substrate when it is previously formed into a film, but is applied to the substrate by an appropriate application method such as screen printing, bar coater, blade coater, etc. In order to obtain the touch drying property, a tack-free coating film is obtained by, for example, drying at about 70 to 120 ° C. for 5 to 40 minutes using a hot air circulating drying furnace or a far infrared drying furnace. Thereafter, selective exposure, development, and baking are performed to form an electrode circuit having a predetermined pattern.

Here, as the exposure step, contact exposure or non-contact exposure using a negative mask having a predetermined exposure pattern is possible. As the exposure light source, a halogen lamp, a high-pressure mercury lamp, a laser beam, a metal halide lamp, a black lamp, an electrodeless lamp, or the like is used. The exposure amount is preferably about 50 to 500 mJ / cm ² .

  As the development process, a spray method, an immersion method, or the like is used. Developers include aqueous alkali metal solutions such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and sodium silicate, and aqueous amine solutions such as monoethanolamine, diethanolamine and triethanolamine, especially about 1.5% by mass or less. A dilute alkaline aqueous solution having a concentration of 5 is preferably used. In this case, the carboxyl group of the carboxyl group-containing resin in the paste may be saponified and the uncured part (unexposed part) may be removed, and is not limited to the developer as described above. Further, it is preferable to perform washing with water and acid neutralization in order to remove unnecessary developer after development.

  In the baking step, the substrate after development is subjected to heat treatment at about 400 to 600 ° C. in air or in a nitrogen atmosphere to form a desired electrode. In addition, it is preferable to set the temperature increase rate at this time to 20 degrees C / min or less.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to the following examples.
In the following description, “parts” are all based on mass unless otherwise specified.

Synthesis Example: Synthesis of Organic Binder A A flask equipped with a thermometer, stirrer, dropping funnel, and reflux condenser was charged with methyl methacrylate and methacrylic acid in a molar ratio of 0.87: 0.13, and dipropylene glycol as a solvent. Monomethyl ether and azobisisobutyronitrile as a catalyst were added and stirred at 80 ° C. for 2 to 6 hours under a nitrogen atmosphere to obtain a resin solution. The resin solution was cooled, methylhydroquinone as a polymerization inhibitor, tetrabutylphosphonium bromide as a catalyst, and glycidyl methacrylate was added at 0.12 to 1 mol of the carboxyl group of the resin under the conditions of 95 to 105 ° C. for 16 hours. Addition reaction was carried out at an addition molar ratio of a molar ratio, and after cooling, the organic binder A was obtained. This organic binder A had a weight average molecular weight of about 20,000 and an acid value of 74 mgKOH / g.
In addition, the measurement of the weight average molecular weight of the obtained organic binder A connects Shimadzu Corporation pump LC-6AD and Showa Denko Co., Ltd. column Shodex (trademark) KF-804, KF-803, KF-802. It was measured by high performance liquid chromatography.

A photosensitive conductive paste was prepared by using the organic binder A thus obtained, blending with the components and blending ratios shown in Table 1, stirring with a stirrer and kneading with a three-roll mill.
Silver powder having an average primary particle size of 0.96 μm and 1.48 μm was used.
The glass powder has a composition range of 50% by mass of Bi ₂ O ₃ , 15% by mass of B ₂ O ₃ , 15% by mass of ZnO, ₂ % by mass of Si _{2 and} 18% by mass of BaO. A material having a point of 444 ° C., a glass softening point of 500 ° C., and a thermal expansion coefficient α ₃₀₀ of 85 × 10 ⁻⁷ / ° C. was used.
In addition, the particle size of glass powder was measured with the wet particle size measuring device, and the particle size of silver powder was measured with SEM.

Composition Example: Composition Using Organic Binder A Organic Binder A 180.0 parts Trimethylolpropane triacrylate 60.0 parts 2-Benzyl-2-dimethylamino-1-
(4-morpholinophenyl) -butanone-1 10.0 parts dipropylene glycol monomethyl ether 20.0 parts Silver powder (particle size is listed in Table 1) 400.0 parts Glass powder (average particle size (D ₅₀ ) = 0 .9 μm, each compounding amount is listed in Table 1)
0.04 to 4.04 parts Phosphate ester 3.0 parts Antifoaming agent (BYK-354: Big Chemie Japan Co., Ltd.) 1.0 part

Test piece preparation:
On the glass substrate, the photosensitive conductive pastes of Examples 1 and 2 and Comparative Examples 1 to 3 were applied to the entire surface using a 200-mesh polyester screen, and then dried at 90 ° C. for 30 minutes in a hot air circulation drying oven. As a result, a coating film with good dryness to the touch was formed. Next, using a metal halide lamp as a light source and exposing through a negative mask so that the integrated light amount on the dried coating film is 300 mJ / cm ² , a 0.5 wt% Na ₂ CO ₃ aqueous solution with a liquid temperature of 30 ° C. It was used for development and washed with water. And the board | substrate with which the coating-film pattern was formed was heated up to 580 degreeC at 5 degree-C / min in air atmosphere, and baked at 580 degreeC for 20 minutes, and the test piece which formed the electrode was produced.
With such a method, each test piece used for the adhesion test, the migration test, and the line resistance value test was produced. That is, L / S (wiring width / wiring interval) = 100/300 μm stripe electrode for adhesion test, comb electrode of L / S = 120/120 μm for migration test, and line resistance value test Produced a line electrode of length × width = 100 mm × 0.1 mm.

(Test method and each evaluation)
Adhesion after firing:
The strip electrode of L / S = 100/300 μm obtained in the above test piece preparation was subjected to a tape peeling test using a cellophane tape, and peeling was confirmed visually.
The evaluation criteria are as follows.
Evaluation of adhesion after firing:
○ ・ ・ ・ No peeling △ ・ ・ ・ Partial electrode peeled off with tape peel

Adhesion after acid resistance test:
The stripe electrode substrate of L / S = 100/300 μm obtained in the above test piece preparation was immersed in a 3% nitric acid aqueous solution heated to 30 ° C. for 3 minutes, and then washed with tap water. After sufficiently drying it, a tape peel test was performed with a cellophane tape, and the peeling of the electrode was confirmed visually.
The evaluation criteria are as follows.
Evaluation of adhesion after acid resistance test:
○ ・ ・ ・ No peeling △ ・ ・ ・ Partial electrode peeled off with tape peel × ・ ・ ・ Electrode peeled off while immersed in acid

Migration test:
A migration test substrate was prepared by applying and curing a UV desiccant to the L / S = 120/120 μm comb electrode obtained in the above test piece preparation. The substrate was tested in a constant temperature and humidity chamber at 85 ° C. and 85% RH with an applied voltage of 150 V and a test time of 96 hours. The substrate after the test was observed with an optical microscope, and dentlite was evaluated.
The evaluation criteria are as follows.
Migration assessment:
○ ・ ・ ・ Dent light not generated △ ・ ・ ・ Dent light generated slightly × ・ ・ ・ Short

Line resistance test:
Data obtained by measuring a line electrode of length × width = 100 mm × 0.1 mm obtained by the above-mentioned test piece preparation using a milliohm high tester manufactured by Hioki Electric Co., Ltd. was taken as a line resistance value.

  As is apparent from the results shown in Table 2, according to the conductive paste of the present invention, the adhesiveness after the acid resistance test is excellent without deteriorating the adhesiveness, conductive properties, and migration resistance properties with the base material after firing. It has been found that an electrode can be provided.

Claims (6)

  (A) an organic binder, (B) a conductive powder having an average primary particle size of 0.5 to 1.4 μm, and (C) a glass powder having a content in an inorganic component of 0.1 to 0.9 wt%. A conductive paste for plasma display, characterized in that. The conductive powder (B) is Ag, Al, Pt, Au, Cu, Ni, In, Sn, Pt, Zn, Fe, Ir, Os, Rh, W, Mo, Ru, and alloys or oxides thereof, _{2. The} conductive paste for plasma display according to claim 1, wherein is at least one selected from the group consisting of SnO ₂ , In ₂ O ₃ , and ITO.   The conductive material for plasma display according to claim 1, wherein the glass powder (C) contains at least one of bismuth oxide, zinc oxide, lithium oxide, and alkali borosilicate as a main component. paste.   The conductive paste for an electrode according to any one of claims 1 to 3, which is a conductive paste used in a method for producing a plasma display including an acid treatment step.   The electrode for plasma displays produced using the electrically conductive paste of any one of Claims 1-3.   A plasma comprising conductive powder having an average primary particle size of 0.5 to 1.4 μm in a proportion of 99.1 to 99.9 wt% and glass powder in a proportion of 0.1 to 0.9 wt%. Display electrode.