JPH1116499A - Plasma display and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance contrast by satisfying the specific relation of the value of the stimulus value of a back electrode layer and the stimulus value of a white electrode layer. SOLUTION: Photosensitive black conductive paste and photosensitive white conductive paste are applied on a glass substrate, and exposed, a part dissolving in a developing solution is removed by development, then baked. At that time, the value Y1 of the stimulus value Y of a black electrode layer and the stimulus value Y2 of a white electrode layer satisfy the relation in formulas I and II. As the color of electrodes, the stimulus value Y of the black electrode layer formed on the glass substrate side, of three stimulus values X, Y, Z of the light source color in an X, Y, Z color system is made 1-20 for example, preferably 4-10 to effectively be consistent with both of low resistance and high contrast. The value of the stimulus value Y of the white electrode layer is preferable to be 70-100 to reduce resistance. In the case that chromaticity coordinates (x), (y), (z) are found based on three stimulus values X, Y, Z, the values of (x), (y) of the black electrode layer are desirable to be 0.28-0.38, preferably 0.30-0.36 to enhance color purity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display used for a large television or a computer monitor.

[0002]

2. Description of the Related Art In recent years, plasma displays have attracted attention as large displays. FIG. 2 shows a structural example of a plasma display. The plasma display is configured by bonding a front plate and a back plate. In the front plate, a transparent electrode made of ITO or tin oxide is formed on the back surface of the glass substrate. A plurality of transparent electrodes are formed in a strip shape. Usually 10 kHz to several tens between these adjacent transparent electrodes.
A pulsed AC voltage of kHz is applied to obtain a discharge for display. However, since the sheet resistance of the transparent electrode is as high as several tens of Ω / cm ² , the electrode resistance becomes about several tens of kΩ, and the imprint voltage pulse does not sufficiently rise. Driving becomes difficult. Therefore, a metal bus electrode is usually formed on the transparent electrode to reduce the resistance value.

Next, these electrodes are covered with a transparent dielectric layer. The transparent dielectric layer uses a low-melting glass containing lead glass or bismuth. Then, as a protective layer, Mg
O is formed by an electron beam evaporation method.

On the other hand, in the rear panel, a data electrode for writing display data on a glass substrate is prepared using a photosensitive silver paste, and is covered with a white dielectric layer. A white or black partition is formed thereon, and a phosphor that emits red, green, and blue light is applied by screen printing, and then dried and fired to form a phosphor layer. (Y, Gd) BO ₃ : Eu is used as the red phosphor powder, (Zn, Mn) ₂ SiO is used as the green phosphor powder, and (Ba, Eu) MgAl ₁₀ O ₇ is used as the blue phosphor powder.

[0005] After sealing the front plate and the rear plate so as to enable matrix driving, exhaust, He, Ne,
A plasma display is manufactured by enclosing a mixed gas of Xe and mounting a drive circuit.

When a pulsed AC voltage is applied between adjacent transparent electrodes, gas discharge occurs, and plasma is formed. The ultraviolet light generated here excites the phosphor to emit visible light and obtain display light emission through the front plate. The transparent electrode that generates a discharge is composed of a scan electrode and a sustain electrode. In an actual panel drive, a sustain discharge pulse is applied to the transparent electrode serving as a discharge electrode.
A voltage is applied between the data electrodes on the back plate to generate a counter discharge, and this discharge is maintained between the discharge electrodes by a sustain pulse.

Further, in order to increase the definition of the plasma display, that is, to increase the number of pixels with a fixed screen size, it is necessary to reduce the size of one pixel. In this case, it is necessary to reduce the pitch between the partition walls. However, when the pitch is reduced, the discharge space is reduced and the coated area of the phosphor is reduced, so that the luminance is reduced. Specifically, in order to realize a 42-inch high-definition television (1920 × 1035 pixels) or a 23-inch OA monitor (XGA: 1024 × 768 pixels), the pixel size must be 450 μm square. It is necessary to form partition walls for each color at a pitch of 150 μm. In this case, if the line width of the partition is large, it is difficult to improve the luminance because a space for discharge cannot be secured or the application area of the phosphor is reduced.

The electrodes of the plasma display are formed by a thick film method,
It is formed by a thin film method or the like. In the thick film method, an electrode is formed by performing pattern processing on a glass substrate using a paste containing metal powder and an organic component as essential components, followed by firing. In the thin film method, after a metal such as chromium or copper is sputtered on a glass substrate, pattern processing is performed using a resist.

[0009]

As the bus electrode layer used for the front panel of the plasma display, it is preferable to use a metal having a low resistance value. Such a metal is usually white. When the color of the electrode is white, the external light incident on the unlit pixel is reflected by the electrode, so that the contrast is reduced. The method of forming a black layer on the outer surface side of the white conductive layer has a disadvantage that conduction between the transparent electrode layer used for the discharge electrode and the white electrode layer cannot be established because the black layer has a large resistance value. Therefore, it is necessary to make the bus electrode layer black.

However, a black conductive material generally has a high resistance value. Further, in the thin film method, blackening is relatively easy by using chromium. However, the thin film method requires a sputtering step, so that the apparatus is expensive and the production efficiency is low. On the other hand, although the thick film method can be made relatively inexpensive, it has a drawback that driving the display becomes difficult because the resistance value tends to increase when blackened. In particular, when a pigment is added to the paste for blackening, there is a problem that the resistance value increases.

An object of the present invention is to produce an electrode layer capable of improving the contrast of a plasma display.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma display in which a black electrode layer and a white electrode layer are formed on a glass substrate, and the value Y of the stimulus value Y of the black electrode layer is provided.
1 and a stimulus value Y2 of the white electrode layer satisfy the following condition.

1 ≦ Y1 ≦ 20 70 ≦ Y2 ≦ 100 Another object of the present invention is to provide a step of applying a photosensitive black conductive paste on a glass substrate, a step of applying a photosensitive white conductive paste, a step of performing exposure, This is achieved by a plasma display manufacturing method in which an electrode is formed by baking at 400 to 720 ° C. after a step of removing a portion dissolved in a developer by development. Further, an object of the present invention is to apply a photosensitive black conductive paste on a glass substrate, to expose, to apply a photosensitive white conductive paste, to perform a re-exposure, and to develop a portion that is dissolved in a developing solution. This is achieved by a method of manufacturing a plasma display in which electrodes are formed by baking at 400 to 720 ° C. after the removing step.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The inventors have found an electrode structure having a two-layer structure of a black electrode layer and a white electrode layer having a specific thickness as an electrode having a low resistance value and a high contrast improving effect in a thick film method. Was.

In this case, among the three stimulus values XYZ of the light source color in the XYZ color system, the values of the stimulus value Y of the black electrode layer formed on the glass substrate side are 1 to 20, 2
It is effective to set the value to 15 and more preferably 4 to 10 to achieve both low resistance and improved contrast. The value of the stimulus value Y of the white electrode layer is not particularly limited, but those having a stimulus value of 70 to 100 usually have a low resistance value.

The tristimulus value XYZ of the light source color and the chromaticity coordinates x, y, z obtained therefrom are described in 6.2 of JIS (Japanese Industrial Standards) Z 8722 (additional items of measured values), J
8.2 of ISZ 8717 (Display of annex to measured values)
6.2 (Additions to the measured values), JIS Z8701
(Color display method-XYZ color system and XYZ color system).

Further, in the plasma display of the present invention, chromaticity coordinates x, y, and x are calculated based on the tristimulus values X, Y, and Z.
When z was obtained, the values of x and y of the black electrode layer were set to 0.28 to
By setting the ratio to 0.38, preferably 0.30 to 0.36, the color purity of the emission color of the plasma display can be improved. As a device for measuring these stimulus values and chromaticity coordinates, generally, a color computer (SM-7-CH or the like) manufactured by Suga Test Instruments Co., Ltd. can be used.

In the present invention, the thickness t of the black electrode layer
1 and the thickness t2 of the white electrode layer preferably satisfy the following conditions. 1 μm ≦ t1 ≦ 10 μm 1 μm ≦ t2 ≦ 10 μm

The electrode of the present invention can be obtained by patterning a black electrode layer and a white electrode layer on a glass substrate. As the glass substrate, a heat-resistant glass substrate such as soda glass or PD-200 manufactured by Asahi Glass Co., Ltd., or a non-alkali glass manufactured by Corning can be used. It is common to use a glass substrate on which a transparent electrode such as ITO or tin oxide is formed.

As a method for forming the black electrode layer and the white electrode layer, a conductive paste composed of various conductive metal powders and an organic binder can be used.

The conductive metal powder used in the present invention includes Ag, Au, Pd, Cu, Ni, Al and Pt.
Containing at least one member selected from the group consisting of Ag,
Au, Pd, Cu, Ni, Al and Pt can be used alone or as a mixed powder. In particular, a conductive metal powder containing 90% by weight or more of silver is preferable in that the resistance value can be reduced.

Ag (80-98) -Pd (20-
2), Ag (90-98) -Pd (10-2) -Pt
(2-10), Ag (85-98) -Pt (15-2)
A mixed noble metal powder of a ternary system or a binary system (the above (in parentheses represents weight%)) is used.

The particle size of the metal powder used in the above is selected in consideration of the shape of the pattern to be produced, and the 50% by weight particle size is preferably 0.1 to 10 μm.

The metal powder has a sphericity of 80% by number.
By using the above metal powder at 50% by weight or more,
Light scattering in the paste can be suppressed by reducing the glass surface area.

Further, it is preferable to use a conductive metal composition that can be baked at a temperature of 600 ° C. or less on a glass substrate, and it is preferable that silver or nickel is contained in a range of 70 to 100% by weight.

It is effective that the electrode contains a glass component in addition to the conductive metal in order to improve the adhesive strength between the electrode layer and the glass substrate layer. The glass component is used to ensure sufficient adhesion between the conductive powder and the glass substrate.
Further, it is necessary because it has a sintering aid for sintering the conductive powder and an effect of lowering the resistance value.

When baking on a glass substrate such as a plasma display, the glass transition temperature (Tg) and the glass softening point (Ts) of the glass component are preferably low, preferably 300 to 500 ° C. and 350 to 450 ° C., respectively. Is good. More preferably, Tg is 350 to 450 ° C.
It is good. If the Tg is lower than 300 ° C., sintering starts before the organic components such as the polymer binder and the monomer evaporate, which is not preferable.

The inventors have intensively studied a glass component having the above characteristics. As a result, the glass frit, by using a glass component containing Bi ₂ O ₃ in the range of 20 to 60 wt%, has been found to satisfy performance. When the amount is less than 20% by weight, when the conductive paste is baked on a glass substrate, the glass transition point and the softening point are not sufficiently controlled, and the effect of increasing the adhesive strength to the substrate is small. If it exceeds 60% by weight, the softening point of the glass frit becomes too low, so that the glass frit is melted before the binder in the paste evaporates. For this reason, the binder removal property of the paste is deteriorated, the sinterability of the conductor film is reduced, and the adhesive strength with the substrate is reduced.

Further, a bismuth-containing borosilicate glass having a composition range of 20 to 60 parts by weight of Bi ₂ O _{3, 3 to} 60 parts by weight of SiO _{2, and} 3 to 60 parts by weight of B ₂ O _{3 in} terms of oxide is used. The electrode can be firmly baked on a glass substrate at 500 to 600 ° C.

It is preferable to mix SiO ₂ in the range of 3 to 60% by weight, and if it is less than 3% by weight, the adhesive strength when baked on the substrate and the stability of the glass component are reduced. On the other hand, if it exceeds 60% by weight, the heat-resistant temperature increases, and it becomes difficult to bake on a glass substrate at 600 ° C. or lower.

It is preferable that B ₂ O ₃ is blended in the range of ₃ to 60% by weight. B ₂ O ₃ is blended to control the baking temperature in the range of 500 to 600 ° C. so as not to impair the electrical, mechanical and thermal properties such as the electrical insulation, strength and coefficient of thermal expansion of the electrode. If the amount is less than 3% by weight, the adhesion strength decreases, and if it exceeds 60% by weight, the stability of the glass component decreases. It is preferable that ZnO is blended in a range of 2 to 20% by weight. If the amount is less than 2% by weight, the effect of controlling the baking temperature when baking the electrodes on the glass substrate is small. If it exceeds 20% by weight, the heat-resistant temperature of the glass will be too low, and it will be difficult to bake it on a glass substrate.

Further, Al ₂ O ₃ , BaO,
The thermal expansion coefficient, glass softening point, glass transition point, and insulation resistance can be controlled by containing CaO, TiO ₂ , ZrO _2, etc., but the amount is preferably less than 15% by weight.

The content of the glass component in the electrode is from 1 to
Preferably it is 10% by weight. More preferably 1 to
5% by weight. In order to reduce the resistance of the electrode of the PDP, it is preferable that the amount of the glass component is low.

Since the glass frit is electrically insulating,
If the content exceeds 5% by weight, the resistance of the electrode increases, which is not preferable. If it is less than 1% by weight, it is difficult to obtain a strong adhesive strength between the electrode film and the glass substrate.

A black electrode can be formed by including 0.5 to 15% by weight of a black metal oxide or metal in the electrode layer. For example, Ag, Au, Pd, Ni,
Ru, Mn, Ni, Cr, F are added to Al and Pt powders.
e, Co metal or their oxides in a total of 0.5
Black can be obtained by mixing 15% by weight. By including at least one, and preferably three or more of these metal oxides, blackening becomes possible. In particular, a black pattern can be formed by containing 0.5% by weight or more of ruthenium oxide.

By adding a metal or metal oxide for blackening to the photosensitive paste of the present invention, the pattern after firing can be blackened.

For coloring black, a black metal or metal oxide may be adhered or coated on the surface of the metal powder.

After various metals or metal oxides are chemically plated on the surface of a base metal powder such as silver, 400 to 5
By baking at 00 ° C. for 30 minutes to several hours, the powder can be blackened. Specifically, the base metal powder is dispersed in an aqueous solution of a desired metal salt or metal complex, a reducing agent is added to the dispersant, the metal is precipitated on the glass powder, and then the metal is fired by firing. Oxidizes to black.

When the amount of the metal oxide added is small by firing, the metal oxide powder adheres uniformly and to the surface of the metal powder. When the amount of addition is large, it is uniformly coated and a thin film is formed. At this time, the metal powder used preferably has an average particle size of 0.5 to 5 μm from the viewpoint of ease of coating.

The metal to be adhered or coated is preferably at least one of Ru, Cr, Fe, Co, Mn, and Ni whose oxides are black. The metal salt or metal complex used is a salt or complex of the above-mentioned metals, and is not particularly limited as long as it is water-soluble. Examples thereof include halides, cyanides, sulfates, nitrates, ammine complexes, nitrosyl complexes, carbonyl complexes, and aqua complexes. preferable.
In particular, for example, in the case of Ru, 2RuCl ₂ (OH) · 7
NH ₃ .3H ₂ O, RuO ₂ (NH ₃ ) ₂ (OH) ₂ , Na ₂
RuO ₄ , K ₂ RuO ₄ , Rb ₂ RuO ₄ , Cs ₂ RuO ₄ ,
(NH ₄ ) ₂ RuO ₄ , Mg ₂ RuO ₄ , Ca ₂ RuO ₄ , S
r ₂ RuO ₄ , Ba ₂ RuO ₄ , Ag ₂ RuO ₄ , Ru (N
O) Cl ₂ · H ₂ O, Ru (NO) Br ₂ · H ₂ O, Ru
(NO) I ₃ is preferred.

The amount of the black oxide to be attached or coated is 0.5 to 15% by weight of the amount of the base metal powder,
It is preferable because it is excellent in pattern formability and sinterability. When the content is less than 0.5% by weight, the blackness is weakened, the image looks grayish, and the contrast is not improved. If it is more than 15% by weight, the softening point will increase and it will be difficult to match the coefficient of thermal expansion with the glass substrate. Further, the blackness becomes too strong, so that the ultraviolet rays do not reach the lower portion, and the pattern formability decreases, which is not preferable.

The sheet resistance of the black electrode layer is 5 to 1
It is important that the resistance is 00 Ω / cm ² in order to establish conduction between the transparent electrode and the white electrode. Further, the paste can be prepared by kneading the white or black metal powder and glass frit with an organic binder.

In this case, a photosensitive conductive paste can be obtained by using a compound containing a photosensitive organic component as the organic binder.

As a method of forming an electrode layer using a photosensitive conductive paste, a photosensitive black conductive paste is applied on a glass substrate, and then a photosensitive white conductive paste is applied, and then exposed and developed. The electrode pattern can be easily formed. This pattern is 400-72
By firing at 0 ° C., the plasma display of the present invention can be obtained.

The method for producing the photosensitive conductive paste will be described below, but the present invention is not limited to this. After blending various components such as conductive metal powder, UV absorber, photosensitive organic component, photopolymerization initiator, glass frit and solvent, additives, etc. to have the prescribed composition, homogenize with three rollers or kneader. Mixed and dispersed. The organic component used in the present invention is an organic component in a paste containing a photosensitive organic substance.

As for the photosensitive paste, the content of the photosensitive component is at least 10% by weight of the organic component, and
It is preferable that the content be not less than% by weight in terms of sensitivity to light.

The organic component contains a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, and, if necessary, a binder, a photopolymerization initiator, an ultraviolet light absorber, Additives such as sensitizers, sensitization aids, polymerization inhibitors, plasticizers, thickeners, organic solvents, antioxidants, dispersants, organic or inorganic suspending agents and leveling agents can also be added. Will be

The photosensitive component includes a photo-insolubilizing type and a photo-solubilizing type. The photo-insolubilizing type includes: (A) a functional monomer having at least one unsaturated group or the like in a molecule; (B) those containing photosensitive compounds such as aromatic diazo compounds, aromatic azide compounds, and organic halogen compounds. (C) So-called diazo resins such as condensates of diazo amines and formaldehyde. And others.

Examples of the photo-soluble type include (D) a complex of a diazo compound with an inorganic salt or an organic acid, and a product containing a quinone diazo compound, and (E) a quinone diazo compound combined with an appropriate polymer binder. For example, there are naphthoquinone 1,2-diazido-5-sulfonic acid ester of phenol and novolak resin.

As the photosensitive component used in the present invention, all of the above can be used. As the photosensitive component which can be easily used as a photosensitive paste by mixing with an inorganic powder, the photosensitive component (A) is preferable.

The photosensitive monomer is a compound containing a carbon-carbon unsaturated bond. Specific examples thereof include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, and sec-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, isodexyl acrylate, isooctyl acrylate, lauryl acrylate, 2-
Methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafluoropentyl 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, methoxide Shi of cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate,
Trimethylolpropane triacrylate, acrylamide, aminoethyl acrylate, phenyl acrylate, phenoxyethyl acrylate, benzyl acrylate, 1-naphthyl acrylate, 2-naphthyl acrylate, bisphenol A diacrylate, diacrylate of bisphenol A-ethylene oxide adduct,
Bisphenol A-propylene oxide adduct diacrylate, thiophenol acrylate, benzyl mercaptan acrylate, and monomers in which 1 to 5 hydrogen atoms of these aromatic rings are substituted with chlorine or bromine atoms, or styrene, p -Methylstyrene,
o-methylstyrene, m-methylstyrene, chlorinated styrene, brominated styrene, α-methylstyrene, chlorinated α
-Methyl styrene, brominated α-methyl styrene, chloromethyl styrene, hydroxymethyl styrene, carboxymethyl styrene, vinyl naphthalene, vinyl anthracene, vinyl carbazole, and part or all of the acrylate in the molecule of the above compound to methacrylate Modified ones include γ-methacryloxypropyltrimethoxysilane, 1-vinyl-2-pyrrolidone and the like. In the present invention, one or more of these can be used.

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 the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

As the binder, polyvinyl alcohol, polyvinyl butyral, methacrylate polymer, acrylate polymer, acrylate-
Examples include methacrylate copolymers, α-methylstyrene polymers, and butyl methacrylate resins.

An oligomer or polymer obtained by polymerizing at least one of the compounds having a carbon-carbon double bond described above can be used. During the polymerization, the monomers can be copolymerized with other monomers such that the content of these monomers is at least 10% by weight, more preferably at least 35% by weight.

As a monomer to be copolymerized, developability after exposure can be improved by copolymerizing an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

The polymer or oligomer having an acidic group such as a carboxyl group in the side chain thus obtained has an acid value (AV) of preferably from 50 to 180, more preferably from 70 to 140. When the acid value is less than 50, the allowable development width becomes narrow. On the other hand, if the acid value exceeds 180, the solubility of the unexposed portion in the developing solution decreases, so that if the developing solution concentration is increased, peeling occurs up to the exposed portion, making it difficult to obtain a high-definition pattern.

By adding a photoreactive group to the polymer or oligomer described above to a side chain or a molecular terminal, the polymer or oligomer can be used as a photosensitive polymer or oligomer having photosensitivity.

Preferred photoreactive groups are those having an ethylenically unsaturated group. As the ethylenically unsaturated group,
Examples include a vinyl group, an allyl group, an acryl group, and a methacryl group.

A method for adding such a side chain to an oligomer or a polymer is based on a method in which an ethylenically unsaturated compound having a glycidyl group or an isocyanate group or an acrylic acid is used for a mercapto group, an amino group, a hydroxyl group or a carboxyl group in the polymer. There is a method in which chloride, methacrylic chloride or allyl chloride is added to make an addition reaction.

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

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

The ethylenically unsaturated compound having a glycidyl group or isocyanate group, acrylic acid chloride, methacrylic acid chloride or allyl chloride is used in an amount of from 0.05 to 0.05 to the mercapto group, amino group, hydroxyl group and carboxyl group in the polymer. It is preferable to add one molar equivalent.

As specific examples of the photopolymerization initiator,
Benzophenone, methyl o-benzoylbenzoate, 4,
4-bis (dimethylamine) benzophenone, 4,4-
Bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4-methyldiphenylketone, dibenzylketone, fluorenone, 2,
2-diethoxyacetophenone, 2,2-dimethoxy-
2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, Benzyl dimethyl ketanol, benzyl methoxyethyl 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-propanedione-2- (o-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o
-Ethoxycarbonyl) oxime, 1-phenyl-3-
Ethoxy-propanetrione-2- (o-benzoyl)
Oximes, Michler's ketones, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinoline sulfonyl chloride, N-phenylthioacridone, 4, 4
-Azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphorphine, camphorquinone, carbon tetrabromide, tribromophenylsulfone, benzoin peroxide and eosin,
Examples include a combination of a photoreducing dye such as methylene blue and a reducing agent such as ascorbic acid and triethanolamine. In the present invention, one or more of these can be used. The photopolymerization initiator is added in a range of 0.05 to 10% by weight, more preferably 0.1 to 5% by weight, based on the photosensitive component. If the amount of the polymerization initiator is too small, the photosensitivity becomes poor, and if the amount of the photopolymerization initiator is too large, the residual ratio of the exposed portion may be too small.

It is also effective to add an ultraviolet absorber. A high aspect ratio, high definition and high resolution can be obtained by adding an absorbent having a high ultraviolet absorbing effect. UV absorbers composed of organic dyes, especially 35
Organic dyes having a high UV absorption coefficient in the wavelength range of 0 to 450 nm are preferably used. Specifically, azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, aminoketone dyes, anthraquinones, benzophenones, diphenylcyanoacrylates, triazines, p-aminobenzoic acid dyes and the like can be used. . Even when an organic dye is added as a light absorbing agent, it is preferable because deterioration of the insulating film characteristics due to the absorbing agent can be reduced without remaining in the insulating film after firing. Among these, azo dyes and benzophenone dyes are preferred. The addition amount of the organic dye is preferably 0.02 to 5% by weight. When the content is less than 0.02% by weight, the effect of adding the ultraviolet absorber is reduced, and the content is 5% by weight.
Exceeding the range is not preferred because the properties of the insulating film after firing deteriorate. More preferably, it is 0.1 to 1% by weight. As a method of adding the ultraviolet light absorber composed of an organic pigment, after dissolving in an organic solvent, kneading at the time of the paste production, in addition to the method of kneading, to prepare a solution in which the organic pigment was previously dissolved in an organic solvent,
Next, there is a method in which a metal powder is mixed with the organic solvent and then dried. By this method, a so-called capsule-like powder in which the surface of each powder is coated with an organic film can be produced.

In the present invention, P contained in the inorganic powder
Metals and oxides such as b, Fe, Cd, Mn, Co, and Mg may react with the photosensitive components contained in the paste, causing the paste to gel in a short time, making application impossible. In order to prevent such a reaction, it is preferable to add a stabilizer to prevent gelation. As the stabilizer used, a triazole compound is preferably used. Among the triazole compounds, benzotriazole works particularly effectively. To give an example of the surface treatment of glass powder with benzotriazole used in the present invention,
After dissolving a predetermined amount of benzotriazole with respect to the inorganic powder in an organic solvent such as methyl acetate, ethyl acetate, ethyl alcohol and methyl alcohol, the solution is immersed in a solution for 1 to 24 hours so that these powders can be sufficiently immersed. Immerse. After immersion, preferably, the powder is naturally dried at 20 to 30 ° C., and the solvent is evaporated to prepare a powder which has been subjected to a triazole treatment. The ratio of the stabilizer used (stabilizer / inorganic powder) is preferably 0.05 to 5% by weight.

A sensitizer is added to improve the sensitivity. Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone, 2,3-bis (4-diethylaminobenzal) cyclopentanone,
2,6-bis (4-dimethylaminobenzal) cyclohexanone, 2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, Michler's ketone,
4,4-bis (diethylamino) -benzophenone,
4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) chalcone, p-dimethylaminocinnamylideneindanone, p-dimethylaminobenzylideneindanone, 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, N-tolyldiethanolamine, N-phenylethanolamine, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 3-phenyl-5-benzoylthiotetrazole, 1-phenyl-5-ethoxycarbonylthiotetrazole and the like. Can be In the present invention, one or more of these can be used. Some sensitizers can also be used as photopolymerization initiators. When a sensitizer is added to the photosensitive paste of the present invention, the amount is usually 0.05 to 10% by weight, more preferably 0.1 to 10% by weight, based on the photosensitive component. 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 portion may be too small.

The polymerization inhibitor is added to improve the thermal stability during storage. Specific examples of the polymerization inhibitor include hydroquinone, monoesterified hydroquinone,
N-nitrosodiphenylamine, phenothiazine, p-
t-butylcatechol, N-phenylnaphthylamine,
2,6-di-t-butyl-p-methylphenol, chloranil, pyrogallol and the like. When adding a polymerization inhibitor, the amount added, in the photosensitive paste,
Usually, it is 0.001 to 1% by weight.

Specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol, glycerin and the like.

An antioxidant is added to prevent oxidation of the acrylic copolymer during storage. Specific examples of antioxidants include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, and 2,6-di-t.
-4-ethylphenol, 2,2-methylene-bis-
(4-methyl-6-t-butylphenol), 2,2-
Methylene-bis- (4-ethyl-6-t-butylphenol), 4,4-bis- (3-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-6
-T-butylphenol), 1,1,3-tris- (2
-Methyl-4-hydroxy-t-butylphenyl) butane, bis [3,3-bis- (4-hydroxy-3-t-
[Butylphenyl) butyric acid] glycol ester, dilaurylthiodipropionate, triphenylphosphite and the like. When adding an antioxidant, the amount added is usually 0.001 to 1% by weight in the paste.

To adjust the viscosity of the solution, an organic solvent may be added to the photosensitive paste of the present invention. The organic solvent used at this time includes methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, Chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid, and the like, and an organic solvent mixture containing at least one of these are used.

The photosensitive paste is usually prepared by mixing various components such as a glass powder, an ultraviolet absorber, a photosensitive polymer, a photosensitive monomer, a photopolymerization initiator and a solvent so as to have a predetermined composition. And homogenously mixed and dispersed with a kneader.

The viscosity of the paste is appropriately adjusted by the addition ratio of an inorganic powder, a thickener, an organic solvent, a plasticizer, a suspending agent, etc., but the range is from 2000 to 200,000 cps.
(Centipoise). For example, when the coating on a glass substrate is performed by a spin coating method, 2000 to 5000 c
ps is preferred. In order to obtain a film thickness of 10 to 20 μm by applying once by a screen printing method, 50,000 to 200,000 cps is preferable. When a blade coater method, a die coater method, or the like is used, 2000 to 20000 cps is preferable.

Next, an example of pattern processing of an electrode layer of a plasma display in the present invention will be described. However, the present invention is not limited to this.

First, a photosensitive black paste is applied on the entire surface or on a glass substrate or a polymer film. As a coating method, a method such as screen printing, a bar coater, a roll coater, and a die coater can be used. The coating thickness can be adjusted by selecting the number of coatings, the mesh of the screen, and the viscosity of the paste. However, when used for an electrode such as a plasma display, a thickness of 10 to 100 μm is required.
It is preferable to apply with a thickness of about 30 μm.

Here, the surface treatment of the glass substrate can be performed in order to enhance the adhesion between the paste and the glass substrate. 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 and the like, or organic metals such as organic titanium, organic aluminum and organic zirconium. 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% is used. Next, the surface treatment solution can be uniformly applied on a substrate by a spinner or the like, and then dried at 80 to 140 ° C. for 10 to 60 minutes to perform a surface treatment. Conductive paste sheet (photosensitive green sheet)
Can be easily applied to the glass substrate by sticking the resin onto the glass substrate.

After the exposure, the photosensitive white electrode paste is applied so that the thickness after drying becomes 2 to 50 μm. As the method of applying, the above-described various methods of applying the photosensitive black conductive paste can be similarly used.

Thereafter, exposure is performed using an exposure apparatus. The exposure is generally performed by a mask exposure using a photomask, as is performed by ordinary photolithography. The mask used depends on the type of photosensitive organic component.
Select either negative or positive type. Alternatively, a method of directly drawing with a laser beam or the like without using a photomask may be used. As the exposure device, a stepper exposure device, a proximity exposure device, or the like can be used.

The active light source used at this time is, for example,
Visible light, near-ultraviolet light, ultraviolet light, electron beam, X-ray, laser light, etc. are preferable. Among them, ultraviolet light is preferable. Etc. can be used. Among these, an ultra-high pressure mercury lamp is preferred.
Exposure conditions vary depending on the coating thickness, but 0.5 to 100
0.5 to 3 using an ultra-high pressure mercury lamp having an output of mW / cm ^2.
Exposure is performed for 0 minutes. In particular, when the exposure amount is 0.3 to 5 J / c
Exposure of about m ² is preferred.

By providing an oxygen shielding film on the surface of the applied photosensitive paste, the pattern shape can be improved. As an example of the oxygen shielding film, a film such as PVA or cellulose, or a film such as polyester is used.

The PVA film is formed by uniformly applying an aqueous solution having a concentration of 0.5 to 5% by weight on a substrate by a method such as a spinner and then drying at 70 to 90 ° C. for 10 to 60 minutes to evaporate water. Let me do it. Further, it is preferable to add a small amount of alcohol to the aqueous solution, since the wettability with the insulating film is improved and the evaporation is facilitated. A more preferred solution concentration of PVA is 1 to 3% by weight. Within this range, the sensitivity is further improved. The reason why the sensitivity is improved by the PVA application is presumed as follows. That is, when the photosensitive component undergoes a photoreaction, it is considered that the presence of oxygen in the air interferes with the photocuring sensitivity. However, the presence of a PVA film improves the sensitivity during exposure because excess oxygen can be blocked, which is preferable. .

When a transparent film of polyester, polypropylene, polyethylene, or the like is used, there is a method in which these films are attached to the photosensitive paste after application.

After coating and drying the photosensitive black conductive paste, 1
A method may be used in which exposure is performed twice and re-exposure is performed after the photosensitive white conductive paste is applied. However, there is a disadvantage that the exposure step is required twice and the process becomes long.

Thereafter, development is performed using a developing solution. In this case, development is performed by a dipping method, a spray method, or a brush method. As the developing solution, an organic solvent in which an organic component in the photosensitive paste can be dissolved can be used. Water may be added to the organic solvent as long as the solvent does not lose its solubility. When a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, development can be performed with an aqueous alkali solution. As the alkali aqueous solution, a metal alkali aqueous solution such as a sodium hydroxide or calcium hydroxide aqueous solution can be used, but it is preferable to use an organic alkali aqueous solution since the alkali component can be easily removed at the time of 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 usually 0.01 to 10% by weight, more preferably 0.1 to 10% by weight.
~ 5% by weight. If the alkali concentration is too low, the unexposed portions are not removed, and if the alkali concentration is too high, the pattern portions may be peeled off and the exposed portions may be corroded, which is not good. The development temperature during development is preferably from 20 to 50 ° C. from the viewpoint of process control.

Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of the paste and the substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. The firing temperature is 400 to 720 ° C. As the firing furnace, a batch-type firing furnace or a belt-type or roller hearth-type continuous firing furnace can be used.

In each of the above steps, a heating step at 50 to 300 ° C. may be introduced for the purpose of drying and preliminary reaction.

The glass substrate having the electrode layer obtained by the above steps can be used on the front side or the back side of the plasma display. Further, it can be used as a substrate of a plasma addressed liquid crystal display.

[0088]

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to this. The concentrations (%) in Examples and Comparative Examples are% by weight unless otherwise specified.

In the example, a photosensitive conductive paste comprising a conductive powder and an organic component was prepared. The solvent (γ-butyrolactone) and the polymer were mixed to form a 40% solution and heated to 60 ° C. with stirring to dissolve all the polymers homogeneously.

The polymer is 40% methacrylic acid (M
AA), a weight average molecular weight obtained by subjecting a copolymer consisting of 30% methyl methacrylate (MMA) and 30% styrene (St) to an addition reaction of 0.4 equivalent of glycidyl methacrylate (GMA) to a carboxyl group. 43
000, a photosensitive polymer having an acid value of 95 was used.

Next, the solution was cooled to room temperature, and a photosensitive monomer, a sensitizer and the like were added and dissolved in the proportions shown in Table 1.
Thereafter, this solution was filtered using a 400-mesh filter to prepare a photosensitive organic component. Here, the photosensitive monomer, photopolymerization initiator, and sensitizer used in the present example are the following compounds.

Photosensitive monomer; trimethylolpropane triacrylate photopolymerization initiator; 2-benzyl-2-dimethylamino-1
-(4-morpholinophenyl) -butanone-1 Sensitizer; 2,4-diethylthioxanthone Then, 0.10% was weighed based on sudan (azo organic dye) and glass powder. Sudan is the chemical formula C ₂₄ H
It is an azo organic dye having ₂₀ N ₄₀ and a molecular weight of 380.45. The sudan is dissolved in acetone, a dispersing agent is added, and the mixture is stirred homogeneously with a homogenizer. The conductive powder is added to the solution, and the mixture is uniformly dispersed and mixed. Then, using a rotary evaporator, a temperature of 150 to 200 ° C is used. And evaporated off the acetone. In this way, a powder in which the surface of the conductive powder was uniformly coated (so-called encapsulated) with a film of an ultraviolet absorbent comprising an organic dye was produced.

Thereafter, the respective components of the organic component were dissolved while being heated to 80 ° C., and thereafter, a conductive powder and a glass frit were added and kneaded with a kneader to prepare a paste. The viscosity was adjusted according to the amount of the solvent. Solvent amount (γ
-Butyllactone) was adjusted to be 10 to 40% in the paste.

The conductive powder has an average particle size of 2.6 μm.
Was used. Glass frit is made of Na ₂ O 6
%, Al ₂ O ₃ 3%, SiO ₂ 27%, B ₂ O ₃ 12
%, ZnO 3%, MgO 7%, ZrO ₂ 5%, B
Glass powder having a composition of i ₂ O ₃ 44% was used. The glass powder was made into a fine powder with an attractor in advance, and powder having an average particle diameter of 0.8 μm was used.

The photosensitive organic component and the conductive powder to which the ultraviolet absorber was added were added so as to have the composition shown in Table 1.
The photosensitive white conductive paste P1 was prepared by mixing and dispersing with three rollers.

Similarly, after the surface of silver powder having an average particle size of 2.6 μm was coated with ruthenium oxide at 2%, the above photosensitive organic components were added so as to have the composition shown in Table 1, and the mixture was rolled with three rollers. By mixing and dispersing, a photosensitive black conductive paste P2 was prepared.

Next, a 30 cm square heat-resistant glass substrate (PD-200 manufactured by Asahi Glass Co., Ltd.) on which a transparent electrode pattern was formed was dried by a screen printing method using a photosensitive white conductive paste P1. The coating was performed so as to have a thickness of 10 μm. Drying was performed at 80 ° C. for 30 minutes. After coating and drying P1, a photosensitive black conductive paste P2 was similarly coated to a thickness of 10 μm after drying.

Next, exposure was performed through a photomask. As the mask, a chrome negative mask having a pitch of 220 μm and a line width of 60 μm (stripe) was used. Exposure is 25
Ultraviolet light exposure was performed using a super high pressure mercury lamp having an output of mW / cm ² at a light amount of 1 J / cm ² . Then, it was immersed in a 0.5% aqueous solution of monoethanolamine to perform development.

Further, the obtained glass substrate was heated at 80 ° C. for 2 hours.
After drying for 0 minutes, baking was performed at the maximum temperature of 560 ° C. (the maximum temperature holding time was 30 minutes). The electrode thickness after firing was 5.5 μm for the white electrode layer and 5.5 μm for the black electrode layer, for a total of 11 μm.
Met.

Table 2 shows the results of determining the stimulus values Y and the values of x and y for the upper and lower surfaces of the obtained electrodes using a microspectrophotometer MSC-5NS.

A low-melting glass paste is applied to the obtained electrode forming substrate, dried, and fired to form a dielectric layer.
Magnesium oxide was formed thereon by electron beam evaporation to a thickness of 0.5 μm to produce a front substrate of a plasma display panel.

This front plate is combined with a back plate on which electrodes, dielectrics, partitions, and phosphor layers are formed, and then sealed and gas-sealed. The structure of the obtained plasma display is shown in FIG. Display was performed by applying a voltage to this panel. The contrast ratio was measured from the luminance when the entire surface was turned on and the reflectance when the light was turned off. The contrast ratio is a photometer MCP manufactured by Otsuka Electronics Co., Ltd.
It measured using D-2000.

COMPARATIVE EXAMPLE 1 The photosensitive white conductive paste P1 was dried to a thickness of 20 μm, and without coating and exposing a photosensitive black glass paste, an electrode having only a white layer was formed. A voltage was applied to the panel manufactured in the same manner to perform display, and the contrast ratio was measured from the luminance when the entire panel was turned on and the reflectance when the panel was turned off. The contrast ratio was measured using a photometer MCPD-2000 manufactured by Otsuka Electronics Co., Ltd.

[0104]

[Table 1]

[Table 2] Abbreviations in the table are shown below.

(The numbers in the structures of the polymers 1 to 3 indicate the molar ratios of the respective monomers.) TMPTA: trimethylolpropane triacrylate PVA: polyvinyl alcohol Sudan: azo red dye, C ₂₄ H ₂₀ N ₄ O Yupi knurls D-50: benzophenone dye (Yupinaru _{D-50) C 13 H 10} O 5 MTPMP: 2- methyl-1- [4- (methylthio) phenyl] -2-morpholino propanone -1 EPA: p-dimethylamino Benzoic acid ethyl ester DET: 2,4-diethylthioxanthone γ-BL: γ-butyrolactone Polymer 1:

Embedded image (Weight average molecular weight: 23000, acid value: 90)

[0106]

According to the present invention, a plasma display having a high contrast can be provided by a simple manufacturing process while keeping the resistance of the bus electrode low.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a plasma display of the present invention.

FIG. 2 is a diagram showing an example of a conventional plasma display.

Claims (9)

[Claims] 1. A plasma display having a black electrode layer and a white electrode layer formed on a glass substrate, wherein a stimulus value Y1 of the black electrode layer and a stimulus value Y2 of the white electrode layer are:
A plasma display characterized by satisfying the following conditions. 1 ≦ Y1 ≦ 20 70 ≦ Y2 ≦ 100 2. The plasma display according to claim 1, wherein the thickness t1 of the black electrode layer and the thickness t2 of the white electrode layer satisfy the following condition. 1 μm ≦ t1 ≦ 10 μm 1 μm ≦ t2 ≦ 10 μm 3. A black electrode layer comprising Ru, Mn, Ni, Cr,
Fe and Co metals or their oxides in total
2. The plasma display according to claim 1, wherein the content is 15% by weight. 4. A black electrode layer comprising Ru, Mn, Ni, Cr,
Fe and Co metals or their oxides are added in a total amount of 0.1.
5 to 15% by weight, totaling 85 to 9 of silver or nickel
2. The plasma display according to claim 1, wherein the content is 9.5% by weight. 5. A black electrode layer comprising: ruthenium oxide 0.5
2. The plasma display according to claim 1, wherein the plasma display uses 10 to 10% by weight and 90 to 99.5% by weight of silver. 6. A step of applying a photosensitive black conductive paste on a glass substrate, a step of applying a photosensitive white conductive paste, a step of exposing, and a step of removing a portion dissolved in a developing solution by development. A method for manufacturing a plasma display in which electrodes are formed by baking at ~ 720 ° C. 7. A step of applying a photosensitive black conductive paste on a glass substrate, a step of exposing, a step of applying a photosensitive white conductive paste, a step of re-exposure, and a step of removing a portion dissolved in a developer by development. After passing through, 400-720
A method for manufacturing a plasma display in which electrodes are formed by baking at a temperature of ℃. 8. A photosensitive black conductive paste containing a photosensitive organic component and a metal of Ru, Mn, Ni, Cr, Fe, Co or an oxide thereof in a total amount of 2 to 15% by weight. 8. A method for manufacturing a plasma display according to claim 6, wherein: 9. The plasma according to claim 6, wherein a metal powder coated with a photosensitive organic component and Ru or its oxide in a total amount of 2 to 10% by weight is used as the photosensitive black conductive paste. Display manufacturing method.