JPH11283508A - Substrate for plasma display and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate with a patterned electrode with thin thickness and low resistance by using conductive paste having conductive powder which has the specified average particle size as an essential component for forming a fine pattern. SOLUTION: The mean particle size of conductive powder is specified to be 0.5-0.2 μm, the thickness of an electrode is preferably 1-4 μm, the conductive powder is preferable to contain Ag or at least one selected from a group comprising Au, Pd, Ni, and Pt, and a dielectric layer is formed on the electrode. Preferably, the tap density of the conductive powder is 3-5 g/cc, the specific surface area of the conductive powder is 0.4-1.5 m<2> /g, a photoreactive compound is contained as a photosensitive organic component, as the photoreactive compound, an acrylate compound or a methacrylate compound is used. Thereby, an electrode with no defect such as disconnection or pinholes and an economical substrate with retarded cracks are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for a plasma display having electrodes formed using a conductive paste and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, demands for higher density, higher definition, and higher reliability in circuit materials and displays have been increasing, and accordingly, improvements in pattern processing techniques have been desired. In particular, various methods have been proposed for miniaturization of the conductor circuit pattern.

For example, a plasma display panel (P
DP) has permeated the fields of OA equipment and information display devices because it can display at a higher speed than a liquid crystal panel and can be easily enlarged. Further, progress in the field of high-definition television is highly expected.

With the expansion of such applications, attention has been paid to color PDPs which are fine and have a large number of display cells. The PDP generates a plasma discharge between an anode electrode and a cathode electrode facing each other in a discharge space partitioned by a partition wall provided between a front glass substrate and a rear glass substrate, and a gas sealed in the space. The display is performed by irradiating the ultraviolet light generated from the fluorescent substance onto the phosphor applied in the discharge space. In this case, the anode electrode and the cathode electrode on the glass substrate have a plurality of linear electrodes arranged in parallel, and the electrodes face each other with a small gap therebetween, and the respective linear electrodes intersect. It is configured to be superimposed so as to face the direction.

A surface discharge type PDP having a three-electrode structure suitable for color display has a plurality of pairs of display electrodes adjacent to each other in parallel and a plurality of address electrodes orthogonal to each pair of electrodes. doing.

The address electrodes have been formed by printing a silver paste or the like on a glass substrate by a screen printing method using a screen printing plate having a corresponding pattern and then firing the silver paste. However, in the screen printing method, it is difficult to reduce the width of the electrode pattern to 100 μm or less even if the size of the screen mesh, pattern accuracy, and printing conditions are optimized, and the electrode cross-sectional shape is “kamaboko”. Therefore, there is a limit in forming a fine pattern. The “kamaboko shape” has a smaller cross-sectional area than the “rectangular shape” even at the same thickness, and thus has a higher resistance. Furthermore, in the screen printing method, the precision of the printing plate is
Since the size of the printing plate increases because of the accuracy of the plate making, the dimensional error of the pattern increases. For this reason, in the case of a PDP having a large area of 25 inches or more, it is technically difficult to produce a high-definition PDP.

Further, in the surface discharge type PDP, partitions are provided on the rear glass substrate in addition to the address electrodes, and thereafter, a phosphor layer is formed. In such a surface discharge type PDP, first, a silver paste serving as an address electrode is printed and dried, and then an insulating glass paste for a partition is superimposed and printed 10 to 15 times so as to have a desired height, and dried. Thereafter, the silver paste and the insulating glass paste are simultaneously fired to form the address electrodes and the partition walls. However, large P
When the position of the partition is adjusted with reference to one end of the glass substrate as the DP becomes higher, a large displacement occurs between the address electrode and the partition at the other end of the glass substrate due to accumulation of errors. For this reason, a back glass substrate for a high-definition plasma display cannot be obtained, and enlargement of the plasma display is extremely limited, and it is necessary to solve the problem.

As methods for improving the disadvantages of the screen printing method, Japanese Patent Application Laid-Open Nos.
-296534 and JP-A-63-205255.
After firing the insulating paste as described in
A method of printing and baking a conductive paste to improve the electrode formation, a method using a photolithography technique for forming an anode electrode, and a method of patterning a conductive paste using a photoresist have been proposed. It is not enough to obtain an electrode that satisfies both low resistance and large size in addition to formation.

Further, Japanese Patent Application Laid-Open No. 63-392504,
JP-A-2-268870, JP-A-3-17169
No. 0 and Japanese Patent Application Laid-Open No. HEI 3-180092 consider the composition of a conductive paste, and use a so-called photosensitive conductive paste in which a photosensitive resin is added as an organic component in the conductive paste to form a fine pattern by photolithography. Although there have been proposals for an electrode having a reduced size and an optimized metal powder diameter, these techniques have not been sufficient as electrodes capable of simultaneously forming a fine pattern, reducing the resistance and increasing the size. In addition, JP-A-3-16
No. 3727, Japanese Patent Laid-Open No. 5-271576,
Although an electrode formed by a photosensitive conductive paste method has been proposed as an electrode for a plasma display panel, it has not been sufficient as an electrode having low adhesiveness and high adhesive strength to a substrate.

In addition, a dielectric layer or a phosphor layer is formed on an electrode in a back glass substrate for a PDP. However, if the electrode is thick, the smoothness of the dielectric layer or the phosphor layer is impaired. Cracks were generated in the firing step of forming the layer, and poor partition wall formation was likely to occur.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate for a plasma display having a patterned electrode which can form a fine pattern, has a small electrode thickness, and has a low resistance, and a method of manufacturing the same. It is in.

[0012]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
In a plasma display substrate in which an electrode pattern is formed on a glass substrate using a conductive paste containing a conductive powder as an essential component, the conductive powder has an average particle size of 0.
This is achieved by a plasma display substrate characterized by having a thickness of 5 to 2 μm.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The substrate for a plasma display of the present invention has a thin film and a low-resistance electrode having high adhesion strength to a glass substrate in a fine pattern, and the electrode is coated with a conductive paste. Are formed through required steps.

According to the present invention, in order to obtain a plasma display having a thin-film, low-resistance electrode, the average particle size of the conductive powder in the conductive paste constituting the electrode is preferably 0.5 to 2 μm.
m is controlled. In the present invention, the average particle size is measured by observing an electrode formed on the plasma display substrate with a scanning electron microscope (for example, Model S-2400 manufactured by Hitachi, Ltd.) and measuring the length of the conductive particles in the longitudinal direction. The diameter was measured for 100 pieces, and the average value was defined as the average particle diameter of the conductive powder. The electrode portion to be observed here is preferably a portion where the electrode surface is not covered with a dielectric layer or the like and is exposed, such as a connection portion with a drive circuit. In the measurement of the particle size, the diameter of the conductive particles in the longitudinal direction can be confirmed, and 100 particles that can be measured are selected and measured. Conductive particles that cannot be confirmed because they overlap with other particles are excluded from the particle size measurement. Was.

When the average particle size is smaller than 0.5 μm,
Since the cohesion is very high, it is difficult to obtain a paste in a state where the powder is highly dispersed. Therefore, when a pattern is formed by the photolithography technique, light transmittance is poor, and it is difficult to form a fine electrode pattern due to obstacles such as scattering. If it is larger than 2 μm,
The surface of the paste-coated film becomes rough, and a thin film having a thickness of 4 μm or less causes pinholes and disconnections, which lowers the yield of electrode pattern formation.

In the present invention, an object is to form a thin film electrode, and the thickness of the electrode is preferably 1 to 4 μm.
More preferably, it is 1.5 to 3.5 μm.

In the present invention, since the electrodes are formed using a conductive paste using the conductive powder having the above average particle size, defects such as pinholes and disconnections are caused even in a thin film electrode having a thickness of 1 to 4 μm. Therefore, it is possible to obtain a low-resistance electrode pattern. Here, the measurement of the electrode thickness is performed by scanning a cross section of the electrode formed on the plasma display substrate with a scanning electron microscope (for example, S-2400 manufactured by Hitachi, Ltd.).
Observed in form) and measured. Alternatively, for example, a portion where the electrode surface is not covered with a dielectric layer or the like but is exposed, such as a connection portion with a drive circuit, is exposed to a stylus type roughness meter (for example, surface roughness manufactured by Kosaka Laboratory Co., Ltd.). Measuring instrument SE-3300)
Measure with

Further, depending on the configuration of the plasma display, a dielectric layer may be formed on the electrode. However, when the electrode is thick, the smoothness of the dielectric layer is impaired at the time of forming the dielectric layer, and cracks and defective partition walls are formed. Cause.

However, in the case of the substrate for a plasma display of the present invention, since the thickness of the electrode can be reduced, the smoothness of the dielectric layer at the time of forming the dielectric layer is improved, and the above problem does not occur. In addition, since the thickness of the dielectric layer itself can be further reduced, it is also preferable to form the dielectric layer on the electrode.

Further, it is economical to reduce the thickness of the electrode, which can contribute to the cost reduction of the plasma display.

In the present invention, the conductive powder, that is, the material of the electrode preferably contains at least one selected from the group consisting of Ag, Au, Pd, Ni and Pt. A metal powder having a low theoretical resistance value that can be baked is used. These can be used alone, as an alloy or as a mixed powder. As an example of the mixed powder, for example, Ag (80 to 98) -Pd (20
~ 2), Ag (90-98) -Pd (10-2) -Pt
(2-10), Ag (85-98) -Pt (15-2)
Binary or ternary mixed metal powders (the above (in parentheses indicate weight%)) can be used.

Among these metal powders, Ag alone can be preferably used from the viewpoint of cost and firing property.

As described above, the conductive paste used for manufacturing the plasma display substrate of the present invention contains conductive powder as an essential component. In addition, the conductive paste contains an organic material which plays a role of a binder or the like. Ingredients are mandatory. As the organic component, a cellulosic derivative or an acrylic polymer having good thermal decomposability is used, but other soluble polymers may be used.

In particular, a photosensitive conductive paste containing a photoreactive compound as an organic component is preferable. In the case of conductive pastes that do not have photosensitivity, patterning is performed by using a screen printing method to form the electrodes or by etching using a photoresist, but if the paste has photosensitivity, pattern exposure and Patterning can be performed in the development process. The firing step is an essential step in any case.

As a preferred example of the method for manufacturing a substrate for a plasma display of the present invention using a photosensitive conductive paste, a photosensitive powder containing a conductive powder having an average particle size of 0.5 to 2 μm and a photosensitive organic component is preferred. There is a method in which a conductive paste is applied on a substrate, and an electrode is formed through the steps of exposure, development, and baking. Hereinafter, this manufacturing method will be described in detail. In this case, the particle size measurement was performed using a laser type particle size distribution analyzer (Microtrack 9320-X10).
0, and a measurement sample was prepared by adding about 0.5 g of conductive powder to about 100 ml of pure water, and the dispersion condition was 380 μA.
(5 minutes).

The shape of the conductive powder is not particularly limited. However, since the resistance becomes lower when a dense conductor film is formed, granular or spherical particles having a large tap density are preferable. In particular, in the present invention, the average particle size of the conductive powder needs to be 0.5 to 2 μm, in terms of enhancing the dispersibility of the conductive powder having such a particle size in the paste,
Preferably, the tap density is 3 to 5 g / cc.

When the tap density is 3 g / cc or more, no pinhole or disconnection occurs in the formed circuit pattern.
Excellent yield of circuit pattern formation. Also 5g / cc
When the content is below, the transmittance of ultraviolet rays used for photosensitization under the paste in the case of using the photolithography technique is excellent.

Accordingly, by setting the tap density within the above range, a dense coating film having good ultraviolet transmittance, excellent electrode pattern accuracy, good paste coatability, and good paste coatability can be obtained.

Further, the specific surface area of the conductive powder is 0.4
It is preferably 1.5 m ² / g. When the specific surface area is less than 0.4 m ² / g, the accuracy of the electrode pattern is reduced. When the specific surface area is more than 1.5 m ² / g, scattering of light is increased at the time of pattern formation, and curing is sufficiently advanced to the lower part of the paste. First, peeling may occur during development.

The photosensitive organic component constituting the photosensitive conductive paste contains a photoreactive compound, and examples of the photoreactive compound include compounds having an active carbon-carbon double bond. As a functional group, vinyl group, allyl group,
Monofunctional and polyfunctional compounds having an acrylate group, a methacrylate group, and an acrylamide group are applied.

Among them, it is preferable to use an acrylate compound or a methacrylate compound as the photoreactive compound. Among the above-mentioned photoreactive compounds, acrylic acid ester compounds and methacrylic acid ester compounds have been developed in various kinds of compounds, so select from them in consideration of reactivity, developability, thermal decomposition, etc. Is possible.

As the photoreactive compound, there are a photo-insolubilized type and a photo-solubilized type, and both can be used. In the present invention, however, the ease of handling and the variety of quality design are considered. A photo-insoluble type is preferably used. For example, a type containing a functional monomer, oligomer, or polymer having at least one unsaturated group in the molecule is preferable.

Specific examples of the photosensitive organic component include, in addition to a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, a photopolymerization initiator and, if necessary, a sensitizer. And those containing an agent.

[0034] Regardless of the presence or absence of photosensitivity, components constituting the conductive paste include a plasticizer, a thickener, a dispersant,
Other additives can be added as needed. Since the organic components added to the conductive paste and the additives composed of various organic components affect the characteristics of the circuit and the electrode in relation to the debinding property, the type and amount of the organic components determine the thermal decomposability. It is important to consider and choose.

The photosensitive conductive paste preferably contains 0.5 to 5% by weight of glass frit, more preferably 1 to 3% by weight, in order to increase the adhesive strength of the conductor to the glass substrate. . In order to reduce the resistance and the thickness of the electrode pattern, the amount of the glass frit is preferably small. Since the glass frit is insulative, if the content exceeds 5% by weight, the resistance increases, and film peeling may occur due to the difference in the thermal expansion coefficient between the conductive powder and the glass frit. If it is less than 0.5% by weight, it is difficult to obtain a strong adhesive strength between the circuit pattern and the glass substrate.

Although the circuit pattern is in close contact with the substrate without adding the glass frit, the circuit pattern has a weak adhesive force and is easily peeled off by vibration, impact or the like. In particular, since a low-temperature fired substrate such as a glass substrate is fired at a temperature of 600 ° C. or lower, the conductive powder may not be completely sintered, and the adhesion may be insufficient.

That is, the glass frit is an important component because it has the effect of increasing the adhesive strength between the conductor and the substrate interface and is a sintering aid for sintering the conductive powder.

The glass frit does not substantially contain alkali metal oxides and / or alkaline earth metals such as sodium oxide, lithium oxide, potassium oxide, barium oxide and calcium oxide, which deteriorate the discharge characteristics of the plasma. Is preferred. This is because there is a problem that the alkali metal component and the alkaline earth metal in the glass frit react with silver in the electrode to cause yellowing. It is presumed that the cause of this is that silver undergoes an ion exchange reaction with an alkali metal or an alkaline earth metal, and the silver turns into a colloid to turn yellow.

In the present invention, the main components of the photosensitive conductive paste are (a) a conductive powder, (b) a photosensitive organic component, and (c) a glass frit. Here, the photosensitive organic component means a monomer, an oligomer, a polymer,
Refers to a photopolymerization initiator. However, monomers, oligomers,
It suffices that at least one of the polymers contains a photoreactive compound. A preferred composition range of these components is, for example, 80 to 90% by weight of a conductive powder, 1 to 3% by weight of a glass frit, a total amount of 9 to 15% by weight of a monomer, an oligomer, and a polymer. , Oligomer, and polymer with respect to the total amount of 5-
30% by weight. The photosensitive conductive paste having the composition in such a range transmits ultraviolet light well at the time of exposure, sufficiently exerts a photocuring function, increases the film strength of the exposed portion at the time of development, and has a fine resolution. A circuit pattern can be formed. Furthermore, the adhesive strength of the conductor after firing is high.

The photosensitive conductive paste may be, for example, a sensitizer, a plasticizer, a dispersant, a stabilizer, a thixotropic agent (thickening agent), if necessary, in addition to the above-mentioned conductive powder, organic component, and glass frit. ), An ultraviolet absorber, a gelling inhibitor, an organic or inorganic suspending agent, an organic solvent, and the like are added to form a slurry of the mixture, and the slurry adjusted to have a predetermined composition is homogenized with a stirrer such as a homogenizer. After mixing, it can be produced by uniformly dispersing with a three roller or kneader.

The viscosity of the photosensitive conductive paste is a conductive powder,
It is adjusted by the composition and type of the glass frit, the addition ratio of the organic component, the thixotropic agent, the organic solvent, the plasticizer, etc., and the range is from 1,000 to 150,000 cps (centipoise). For example, 1,000 to 100,000 cps is preferable for obtaining a film thickness of 2 to 10 μm by coating the glass substrate with a screen printing method, a bar coater, a roller coater, or an applicator once or twice by a screen printing method.

When the photosensitive conductive paste is applied on a glass substrate, it is preferable to perform a surface treatment on the substrate in order to increase the adhesion between the applied surface and the applied film. As the surface treatment solution, a known silane coupling agent or a solution obtained by diluting an organic metal with an organic solvent is used. After such a surface treatment liquid is uniformly applied on a substrate by a spinner or the like, the coating is applied at 80 to 140 ° C.
Surface treatment can be performed by drying for 0 to 60 minutes.

Next, the film obtained by coating the photosensitive conductive paste on the glass substrate is dried by heating at 70 to 120 ° C. for 20 to 60 minutes to evaporate the solvent, and then the electrode pattern is formed by photolithography. The photosensitive conductive paste is exposed to light by irradiating it with ultraviolet rays through a negative film or a mask such as a chrome mask.

The actinic rays used for the exposure are most preferably ultraviolet rays. As the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a halogen lamp and the like are used. Exposure conditions vary depending on the applied thickness of the photosensitive conductive paste, but it is preferable to perform exposure using an ultrahigh pressure mercury lamp having an output of 5 to 100 mW / cm ² for 0.1 to 30 minutes.

After exposure, development is carried out using the difference in solubility between the exposed part and the unexposed part in the developing solution.
An immersion method, a spray method, a brush method, or the like is used. As the developer, a solution in which an organic component in the photosensitive conductive paste, in particular, an oligomer or a polymer can be dissolved is used. The oligomer or polymer of the photosensitive conductive paste used in the present invention preferably has a carboxyl group in a side chain, and these can be developed with an aqueous alkali solution.
As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, an aqueous solution of calcium hydroxide and the like can be used,
It is preferable to use an organic alkali aqueous solution because the alkali component can be easily removed during firing.

As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, diethanolamine and the like. The concentration of the alkaline aqueous solution is preferably 0.05 to 5% by weight, more preferably 0.1 to 2% by weight. If the alkali concentration is too low, the soluble portion will not be completely removed, and if the alkali concentration is too high,
There is a possibility that the pattern of the exposed portion may be peeled off or eroded. The development is preferably performed at a temperature of 20 to 50 ° C. in terms of process control.

The electrode pattern formed from the coating film of the photosensitive conductive paste through the steps of exposure and development is then fired in a firing furnace to thermally decompose and remove organic components and simultaneously melt the glass frit. An electrode is formed while ensuring adhesion to a glass substrate.

The baking is performed, for example, at a temperature of 540 to 600 ° C. for 10 to 60 minutes. If the temperature is lower than 540 ° C., unsatisfactory firing results in reduced denseness of the obtained electrode, increased specific resistance, and reduced adhesive strength to the glass substrate, which is not preferable. If the temperature exceeds 600 ° C., the glass substrate is thermally deformed, and the flatness of the pattern is reduced.

In the present invention, the average particle diameter is particularly 0.5 to 2 μm.
m, an Ag powder having a specific surface area of 0.4 to 1.5 m ² / g, a glass frit, and a photosensitive conductive paste containing an acrylate compound or a methacrylate compound as an organic component are applied on a glass substrate and exposed. , Development and baking, the thickness is 1-4 μm
And a substrate for a plasma display on which the most suitable electrodes having the following are formed.

[0050]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments. However, the present invention is not limited to this. The concentrations in the examples are% by weight unless otherwise noted.

The meaning of each evaluation in Tables 1 and 2 is as follows.

(1) Disconnections and pinholes: The presence of disconnections and pinholes (excluding disconnections and pinholes due to contamination of the glass substrate and foreign matter) caused by the conductive paste is determined by an optical microscope and visual judgment on the entire surface of the prepared sample. (2) Edge curl: The height from the glass substrate surface at the upper end of the edge was measured with respect to a cross section of the electrode in the width direction using a scanning electron microscope (SEM) or a stylus type roughness meter. ,
When the height exceeds twice the thickness (3) ○: Acceptable product without disconnection, pinhole, edge curl (4) ×: Rejected product with disconnection, pinhole, edge curl Example 1 Conductive powder A silver powder having a specific surface area of 1.2 m ² / g and a tap density of 4 g / cc was prepared.

88 parts by weight of conductive powder, glass frit 3
Parts by weight, 7 parts by weight of a photosensitive polymer (X-4007), 4 parts by weight of a photosensitive monomer (trimethylolpropane triacrylate), and a photopolymerization initiator (2-methyl-1- [4-
(Methylthio) phenyl] -2-morpholino-propanone-1) 1.6 parts by weight, sensitizer (DETX-S) 0.
8 parts by weight, 0.5 parts by weight of a plasticizer (dibutyl phthalate), 3 parts by weight of a thickener (SiO ₂ (concentration 15%) dissolved in 2- (2-butoxyethoxy) ethyl acetate) and a solvent (γ-butyrolactone) ) 10 parts by weight were dissolved, mixed and dispersed, and kneaded uniformly with three rollers to prepare a photosensitive conductive paste. The paste viscosity was 6000 cps.

The composition of the glass frit (oxide notation,%) used for the paste was bismuth oxide (85), silicon oxide (7.5), boron oxide (2.3), and zinc oxide (2.
1) and aluminum oxide (1.1). This glass frit is benzotriazole (anti-gelling agent)
And used. The amount of benzotriazole used in the treatment was 4.5% based on the glass frit.

The glass frit has a glass transition point of 4
60 ° C., softening point 540 ° C., average particle size 0.8 μm, top size 3.5 μm, and α ₅₀ to ₄₀₀ 73 × 10 ⁻⁷ / K.

This photosensitive conductive paste was applied to 25 cm × 35
It was applied to a glass substrate of cm square by a screen printing method. The coating was performed using a printing plate made of a 350 mesh polyester screen, and the printing conditions were examined to prepare coating films having a thickness of 4 and 6 μm. Next, the coating film was dried at 80 ° C. for 40 minutes.

Electrode pattern (stripe, pitch 14
0 μm, line width 50 μm) through a negative photomask having a power of 15 mW / cm ² and a high pressure mercury lamp of about 30 mW / cm ^2.
UV exposure for 2 seconds was performed.

The development was carried out with a shower of a 0.2% aqueous solution of monoethanolamine at 30 ° C. to remove unexposed portions. Thereafter, the remaining developer was washed away with a shower of pure water and dried at 80 ° C. for 20 minutes.

The firing was carried out by raising the temperature at a rate of 250 ° C./hour and maintaining the maximum temperature at 590 ° C. for 15 minutes.

The electrodes formed on the plasma display substrate thus obtained each had a thickness of 1.
8 μm and 3 μm, and the cross section of the electrode line was rectangular. The specific resistance was 3 μΩ · cm.

Example 2 The average particle size of the conductive powder was 0.6, 1.1, 1.5,
An electrode was formed in the same manner as in Example 1, except that silver and silver particles of 2.0 and 3 μm were used, the coating thickness was changed, and the electrode thickness after firing was set to 1, 2, 3, 4 and 5 μm. Formation was observed. The coating thickness was adjusted using an applicator while changing the clearance with the substrate.

Table 1 shows the state of the electrode obtained after the firing.

[0063]

[Table 1] From these results, it is clear that the smaller the average particle size of the conductive powder, the smaller the thickness of the electrode film can be formed. When the average particle size of the conductive powder is in the range of 0.5 to 2 μm, It becomes possible to form a thin film electrode having a thickness of 4 μm.

Example 3 Two kinds of photosensitive conductive pastes using silver particles having average particle diameters of 1.3 μm and 3 μm were prepared as conductive powders.
An electrode was formed in the same manner as in Example 1, except that the coating was performed using three types of screen printing plates having different meshes.
Table 2 shows the thickness (after firing) of the formed electrodes and the state of occurrence of defects.
Shown in

[0065]

[Table 2] When a paste using silver particles having an average particle size of 3 μm is applied, an electrode having no defect can be obtained when the electrode thickness is 5 μm or more. When a paste using silver particles having an average particle diameter of 1.3 μm in the middle of the range of 0.5 to 2 μm shown in the present invention is applied, an electrode having an electrode thickness of 2.5 to 4 μm and having no defect is obtained. It is clear that

Example 4 A conductive powder having an average particle diameter of 1.5 μm and a specific surface area of 0.4, 0.6, 1.0, 1.3 and 1.5 m ² / g
Silver particles were prepared. An electrode was produced in the same manner as in Example 1, except that five types of photosensitive conductive pastes were produced using conductive powders having different specific surface areas. The viscosity of each paste was 6000 cps, and the applied thickness of the electrode was 4 μm. As in Example 1, the electrode thickness was 2 μm, there were no defects such as disconnection and pinholes, and the specific resistance was 3 μΩ · c.
A plasma display having m electrodes was obtained.

Example 5 On the glass substrate on which an electrode having a thickness of 2 μm obtained in Example 4 was formed, a dielectric paste comprising low-melting glass fine particles of an alkali-free metal and methyl cellulose was dried to a dry thickness of 8 μm. Was applied by a screen printing method. A dielectric coating film having good flatness was formed, and a 5.5-μm-thick dielectric layer obtained by firing this film did not generate cracks near the electrode portion.

Description of abbreviations X-4007: weight average molecular weight obtained by addition-polymerizing 0.4 equivalent of glycidyl methacrylate to a carboxyl group of a copolymer composed of 40% methacrylic acid, 30% methyl methacrylate, and 30% styrene. 43,000, a polymer having an acid value of 95.

DETX-S: 2,4-diethylthioxanthone

[0070]

According to the present invention, there is provided a plasma display substrate formed by forming an electrode pattern on a glass substrate using a conductive paste containing conductive powder as an essential component. The particle size is 0.5-2 μm. Therefore, a fine pattern can be formed, a thin-film electrode can be formed, and an electrode having a practical specific resistance value without defects such as disconnection and pinholes can be obtained. Further, the present invention is an economical substrate for a plasma display which can reduce the thickness of a dielectric layer formed thereon and suppress occurrence of defects such as cracks.

Claims (13)

[Claims] 1. A plasma display substrate having an electrode pattern formed on a glass substrate using a conductive paste containing a conductive powder as an essential component, wherein the conductive powder has an average particle size of 0.5 to 2 μm. A substrate for a plasma display, comprising: 2. The plasma display substrate according to claim 1, wherein the electrode has a thickness of 1 to 4 μm. 3. The plasma display substrate according to claim 1, wherein the conductive powder contains at least one selected from the group consisting of Ag, Au, Pd, Ni and Pt. 4. The plasma display substrate according to claim 1, wherein the conductive powder is Ag. 5. The plasma display substrate according to claim 1, wherein a dielectric layer is formed on the electrode. 6. A photosensitive conductive paste containing a conductive powder having an average particle size of 0.5 to 2 μm and a photosensitive organic component is applied on a glass substrate, and exposed to light, developed and fired to form an electrode. Forming a plasma display substrate. 7. The method according to claim 6, wherein the thickness of the electrode is 1 to 4 μm. 8. The method according to claim 6, wherein the conductive powder contains at least one selected from the group consisting of Ag, Au, Pd, Ni and Pt. 9. The method according to claim 6, wherein the conductive powder contains Ag. 10. The conductive powder has a tap density of 3 to 5 g / c.
The method for manufacturing a substrate for a plasma display according to any one of claims 6 to 9, wherein the method is c. 11. The conductive powder has a specific surface area of 0.4 to 1.5.
method of manufacturing a substrate for a plasma display according to any one of claims 6-10, characterized in that the m ² / g. 12. The method for producing a substrate for a plasma display according to claim 6, wherein a photoreactive compound is contained as a photosensitive organic component. 13. The method according to claim 12, wherein an acrylate compound or a methacrylate compound is used as the photoreactive compound.