JP4867326B2 - Plasma display panel - Google Patents

Description

  The present invention relates to a plasma display panel having high display quality, low display power, and less discharge abnormality.

  Plasma displays are attracting attention as displays that can be used in thin and large televisions. As shown in the schematic diagram of FIG. 5, for example, the glass substrate on the front plate side serving as the display surface has a plurality of pairs of sustain electrodes and scan electrodes made of silver, chromium, aluminum, nickel, or the like. The material is formed in stripes with the column direction being the longitudinal direction when the short side direction of the display region is the row direction and the long side direction is the column direction. The center position of the pair of sustain electrode and scan electrode corresponds to the center line of the cell in the row direction, and the middle position between the center lines of adjacent cells corresponds to the boundary line of the cell in the row direction. In order to maintain the contrast at the time of image display, a black stripe pattern is generally formed on the boundary line between cells adjacent in the row direction as shown in FIG.

  Further, a dielectric layer mainly composed of glass is formed by covering the sustain electrode with a thickness of 20 to 50 μm, and a protective layer made of MgO is formed by covering the dielectric layer.

  On the other hand, on the glass substrate on the back plate side, a plurality of address electrodes are formed in a stripe shape whose longitudinal direction is the row direction, and a dielectric layer mainly composed of glass is formed covering the address electrodes. . A partition for partitioning the discharge cells is formed on the dielectric layer, and a phosphor layer is formed in a discharge space formed by the partition and the dielectric layer. In a plasma display capable of full color display, the phosphor layer is configured to emit light in each color of red (R), green (G), and blue (B). Assuming that the center line of the partition walls adjacent in the column direction is the cell boundary line in the column direction, the cells corresponding to R, G, and B are collectively one pixel. The front plate and the back plate are sealed so that the sustain electrode of the glass substrate on the front plate side and the address electrode on the back plate side are orthogonal to each other, and helium, neon, xenon, etc. are formed in the gap between the substrates. A rare gas is enclosed to form a plasma display. The plasma display has a plurality of pixels and can display an image.

  When performing display on the plasma display, if a voltage higher than the discharge start voltage is applied between the sustain electrode and the address electrode from a state where no light is emitted in the selected cell, positive ions and electrons generated by ionization are stored in the pixel cell. Is a capacitive load and moves toward the opposite polarity electrode in the discharge space and charges the inner wall of the MgO layer. The inner wall charge is not attenuated due to the high resistance of the MgO layer, and becomes a wall charge. Remains.

  Next, a sustaining voltage is applied between the scan electrode and the sustain electrode. Where there is a wall charge, it can be discharged even at a voltage lower than the discharge start voltage. The xenon gas in the discharge space is excited by the discharge, and ultraviolet light having a wavelength of 147 nm is generated, and the ultraviolet light excites the phosphor, thereby enabling light emission display.

In such a plasma display, the address electrode pattern formed on the substrate is usually a strip-shaped electrode having a uniform thickness. However, in recent years, a part of the strip-shaped electrode has been stripped to improve discharge efficiency. Electrode patterns have been proposed (see, for example, Patent Documents 1 and 2). When a thick strip pattern is formed on the address electrode, the total area of the address electrode increases, which increases reactive power and power consumption. Therefore, it is large only in areas where discharge abnormalities such as non-lighting are likely to occur. A contrivance is made such that a thick strip pattern is formed and the other portions are not formed with a thick strip pattern or the size of the pattern is made as small as possible. However, with this method, at the part where the size of the thick band pattern changes, the light emission luminance of the panel suddenly changes and the display quality deteriorates, or the address electrode is inspected in the manufacturing process of forming the address electrode. In this case, there is a problem that a portion where the pattern size changes is erroneously detected as a defect.
JP 2001-126629 A JP 2005-85754 A

  The problem to be solved by the present invention is that the display quality of the display deteriorates because the brightness of the plasma display changes abruptly depending on the position, or erroneous detection frequently occurs during inspection in the manufacturing process of the member, thereby reducing the production efficiency. Accordingly, it is an object of the present invention to provide a plasma display panel with low display power and less discharge abnormality.

  That is, the present invention includes a plurality of address electrodes on a substrate, a dielectric layer covering the address electrodes, and a plurality of address electrodes on the dielectric layer between at least the address electrodes and partitioning a discharge space at least for each unit. A back plate having a partition wall, a plurality of sustain electrode and scan electrode pairs provided on the substrate in a direction substantially orthogonal to the address electrodes, and a dielectric layer covering the sustain electrode and scan electrode pairs; And a front panel having a protective layer on the dielectric layer, each address when the maximum value of the width of the address electrode in each cell is the maximum electrode width in the cell. There are two or more different types of maximum electrode width in a cell, and the difference between the maximum electrode widths in cells adjacent to each other in the row direction is all within the display area. It is an essence a plasma display panel, characterized in that 0μm or less.

  According to the present invention, the brightness of the plasma display changes suddenly depending on the position, the display quality of the display is lowered, and there are many false detections during inspection in the manufacturing process of the member, without reducing the production efficiency, It is possible to provide a plasma display panel that can obtain a plasma display with low display power and low abnormal discharge.

  Hereinafter, the configuration of the plasma display panel of the present invention, the configuration of the back plate used in the plasma display panel of the present invention, and the manufacturing method will be described.

  In the present invention, the cell refers to a region surrounded by a partition line and a center line of the auxiliary partition when the back plate has an auxiliary partition described later.

  Further, when the back plate does not have an auxiliary partition described later, it corresponds to the center line of the center cell of the sustain electrode and the scan electrode that make a pair, and the intermediate position of the center line of the adjacent cell is in the longitudinal direction of the address electrode. This corresponds to a cell boundary line, and the center line of the partition corresponds to a cell boundary line in a direction perpendicular to the longitudinal direction of the address electrode, and indicates a region surrounded by these boundary lines.

  On the glass substrate on the front plate side, a plurality of pairs of sustain electrodes and scan electrodes are made of a material such as silver, chromium, aluminum, or nickel. The short side direction of the display area is the row direction, and the long side direction is the column. It is formed in a stripe shape whose longitudinal direction is the column direction when the direction is set. As shown in the schematic diagram of FIG. 1, if the center position of the sustain electrode and the scan electrode that make a pair is the center line of the cell in the row direction, and the middle position of the center line of the adjacent cells is the boundary line of the cell in the row direction, A black stripe pattern may be formed on the boundary line between cells adjacent to each other in the row direction in order to maintain contrast during image display.

  Further, a dielectric layer mainly composed of glass is formed with a thickness of 20 to 50 μm by covering the sustain electrode, and an MgO layer is formed by covering the dielectric layer. On the other hand, on the glass substrate on the back plate side, a plurality of address electrodes are formed linearly with the row direction as the longitudinal direction, and a dielectric layer mainly composed of glass is formed covering the address electrodes. . A partition wall for partitioning cells is formed on the dielectric layer, and a phosphor layer is formed in a discharge space formed by the partition wall and the dielectric layer. In a plasma display capable of full color display, the phosphor layer is configured to emit light in each color of red (R), green (G), and blue (B). As shown in the schematic diagram of FIG. 1, if the center line of the partition walls adjacent in the column direction is the boundary line of the cells in the column direction, three cells corresponding to R, G, and B are collectively one pixel.

  Next, the configuration and manufacturing method of the back plate used in the plasma display panel of the present invention will be described. As the substrate of the back plate for plasma display used in the plasma display panel of the present invention, soda glass or the like can be used. Specifically, PD200 manufactured by Asahi Glass Co., Ltd., which is heat resistant glass for plasma display, or NEC Examples thereof include PP8 manufactured by Glass Co., Ltd.

  On the substrate, an address electrode is formed of a metal such as silver, aluminum, chromium, or nickel. As a forming method, a metal paste mainly composed of these metal powders and an organic binder is subjected to pattern printing by screen printing, and heated and baked at 400 to 600 ° C. to form a metal pattern, or on a glass substrate. There is an etching method in which a metal such as chrome or aluminum is sputtered, a resist is applied, the resist is subjected to pattern exposure / development, and unnecessary portions of the metal are removed by etching. In particular, after applying a photosensitive metal paste containing a metal powder and a photosensitive organic component, after pattern exposure using a photomask, unnecessary portions are dissolved and removed in a development step, and further heated and baked at 400 to 600 ° C. The photosensitive paste method for forming the metal pattern is preferable because the address electrode can be formed with a high yield because the manufacturing process is simple.

  The address electrodes are formed at a pitch corresponding to the cell. It is preferable to form at a pitch of 100 to 500 μm for a normal plasma display and 100 to 400 μm for a high definition plasma display.

  The electrode thickness is preferably 1 to 10 μm, and more preferably 1.5 to 8 μm. If the electrode thickness is too thin, the resistance value tends to be large and accurate driving tends to be difficult, and if it is too thick, a large amount of material is required, which tends to be disadvantageous in terms of cost.

  In the plasma display panel of the present invention, as shown in FIG. 2, when the maximum value of the address electrode width in each cell is defined as the maximum electrode width in the cell, the maximum value of the maximum electrode width in the cell in the display region is preferably It is preferable that it is 50-200 micrometers, More preferably, it is 80-180 micrometers. Maximum address electrode width If the maximum electrode width in the cell is too thin, the effect of accumulating charges in the cell will be small, and normal discharge will tend to be difficult.If it is too thick, reactive power will increase and power consumption will increase. It tends to increase. In the plasma display panel of the present invention, each address electrode in the display area needs to have two or more maximum cell electrode widths different in the row direction. Here, having two or more different in-cell electrode widths means that the difference between the maximum value and the minimum value of the maximum electrode width in the cell in the display area of each address electrode is 10 μm or more. By increasing the maximum electrode width in the cell only at a portion where discharge abnormality such as non-lighting is likely to occur and by forming it thin at other portions, it is possible to achieve both discharge abnormality suppression and power consumption increase suppression. When the difference between the maximum value and the minimum value of the maximum electrode width in the cell of each address electrode is smaller than 10 μm, a problem that discharge abnormality such as non-lighting occurs or the address electrode width is required to suppress abnormal discharge. If the thickness is increased, there arises a problem that power consumption increases.

  The difference between the cell maximum electrode widths in the cells adjacent to each other in the row direction in the display region needs to be 10 μm or less, and more preferably 7 μm or less. If the difference in the maximum electrode width in the cell between adjacent cells in the row direction exceeds 10 μm, the light emission luminance of the panel changes suddenly at the place where the maximum electrode width in the cell changes, and the display quality is lowered. Arise.

  Further, in all the address electrodes, it is preferable that the difference between the maximum value and the minimum value of the maximum cell electrode width of 10 cells continuous in the row direction is 50 μm or less. If the difference between the maximum and minimum maximum electrode widths in 10 cells in the row direction is too large, the light emission brightness of the panel changes rapidly at the place where the maximum value of the address electrode width changes, and the display quality is reduced. If the defect inspection is performed in the manufacturing process in which the address electrode is formed, the defect is erroneously detected as a defect, and the production efficiency tends to be lowered. There may be a portion in which the difference between the cell maximum electrode widths in cells adjacent in a row direction is 0 μm, or the maximum value and the minimum value of the cell maximum electrode widths in a certain 10 cells continuous in the row direction. There may be a portion where the difference is 0 μm.

  It is preferable that the maximum in-cell electrode width at any end in the row direction in the display region of the address electrode in the center in the column direction is larger than the maximum in-cell electrode width in the cell in the center in the row direction of the address electrode. . In other words, discharge abnormalities such as non-lighting are likely to occur near the edge of the display area in the row direction.Thus, the address electrode is formed thick in this area, and the power consumption is increased in the center of the display area where discharge abnormalities are unlikely to occur. In order to suppress, it is preferable to form thinly.

  In the display area, the difference between the maximum value and the minimum value of the maximum electrode width in the cell is preferably 11 to 150 μm, more preferably 11 to 100 μm. If the difference is too small, the effect of suppressing discharge abnormality is not sufficient, and if the difference is too large, power consumption tends to increase.

  The address electrode is a cell in the display region, and it is preferable that a part of the thin strip electrode is formed in a thick strip shape. Discharge abnormalities such as non-lighting can be suppressed by forming a part in a thick band, and the reactive power is increased unnecessarily and the power consumption is increased by leaving a thin band part. be able to.

  When the minimum value of the address electrode width in the cell is the minimum electrode width in the cell, the maximum value of the difference between the maximum electrode width in the cell and the minimum electrode width in the same cell is 30 to 150 μm in the display area. It is preferable, More preferably, it is 40-120 micrometers. If the maximum value of the difference between the maximum electrode width in the cell and the minimum electrode width in the cell is too small, the effect of suppressing discharge abnormality is not sufficient, and if the maximum value of the difference is too large, power consumption tends to increase.

  A dielectric layer is formed to cover the address electrodes. The dielectric layer can be formed by applying a glass paste containing glass powder and an organic binder as main components so as to cover the address electrodes, and then baking at 400 to 600 ° C. The glass paste used for the dielectric layer preferably contains at least one of lead oxide, bismuth oxide, zinc oxide and phosphorus oxide, and low melting point glass powder containing 10 to 80% by weight of these in total. it can. By making this blend 10% by weight or more, firing at 600 ° C. or less becomes easy, and by making it 80% by weight or less, crystallization is prevented and a decrease in transmittance is prevented.

  These low melting glass powders and an organic binder are kneaded to prepare a paste. As the organic binder to be used, cellulose compounds typified by ethyl cellulose, methyl cellulose and the like, acrylic compounds such as methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, methyl acrylate, ethyl acrylate and isobutyl acrylate can be used. Moreover, you may add additives, such as a solvent and a plasticizer, in glass paste. As the solvent, general-purpose solvents such as terpineol, butyrolactone, toluene and methyl cellosolve can be used. As the plasticizer, dibutyl phthalate, diethyl phthalate, or the like can be used. By adding a filler component having a high softening temperature and not softening during firing, in addition to the low-melting glass powder, a PDP having a high reflectance and a high luminance can be obtained. As the filler, titanium oxide, aluminum oxide, zirconium oxide and the like are preferable, and it is particularly preferable to use titanium oxide having a particle diameter of 0.05 to 3 μm. The filler content is preferably a glass powder: filler mass ratio of 1: 1 to 10: 1. By setting the filler content to 1/10 or more of the glass powder content, the effect of improving the luminance can be obtained. Moreover, sinterability can be maintained by setting it as the same amount or less as content of glass powder.

  Further, by adding conductive fine particles to the glass paste used for the dielectric layer, a plasma display with high reliability during driving can be produced. The conductive fine particles are preferably metal powders such as nickel and chromium, and the volume average particle diameter is preferably 1 to 10 μm. When the thickness is 1 μm or more, a sufficient effect can be exhibited, and when the thickness is 10 μm or less, unevenness on the dielectric can be suppressed, and formation of a partition wall described later on the dielectric layer can be facilitated. As content in which these electroconductive fine particles are contained in a dielectric material layer, 0.1-10 mass% is preferable. When the content is 0.1% by mass or more, conductivity can be obtained, and when the content is 10% by mass or less, a short circuit between adjacent address electrodes in the horizontal direction can be prevented. The thickness of the dielectric layer is preferably 3 to 30 μm, more preferably 3 to 15 μm. If the thickness of the dielectric layer is too thin, pinholes tend to occur frequently, and if it is too thick, the discharge voltage tends to be high and the power consumption tends to increase.

  In the plasma display member of the present invention, partition walls for partitioning pixels in the column direction are formed on the dielectric layer. An auxiliary partition may be formed in a direction perpendicular to the partition so as to partition the pixels in the row direction.

  The partition walls and the auxiliary partition walls are preferably mainly composed of low melting point glass. The main component referred to in the present invention means a component constituting 70% by weight or more, preferably 80% by weight or more, of all components constituting the partition wall.

  When the auxiliary partition is formed, the partition and the auxiliary partition are formed so as to be orthogonal to each other. By forming the auxiliary barrier ribs, when voltage is applied, it is possible to suppress the loss of charge to pixels adjacent in the vertical direction, and the distance between the sustain electrodes (main gap) that contributes to the light emission of the front plate is widened. can do. By widening the main gap, it is possible to increase the luminance because ultraviolet rays efficiently act on the phosphor screen.

  The cross-sectional shape of the partition wall and the auxiliary partition wall can be a trapezoid or a rectangle. The top width of the partition wall is preferably 25 to 80 μm, and more preferably 30 to 75 μm. If the top width of the partition walls is less than 25 μm, the strength is low, and problems such as collapse of the partition walls during sealing with the front plate tend to occur. On the other hand, when the thickness exceeds 80 μm, the formation area of the phosphor layer is reduced, and the luminance tends to be lowered. The bottom width of the partition wall is preferably 1 to 2.3 times the top width, more preferably 1.1 to 2 times.

  The height of the partition walls is preferably 80 to 180 μm, and more preferably 90 to 150 μm. By setting the thickness to 80 μm or more, the phosphor and the scan electrode can be prevented from being too close to each other, and the phosphor can be prevented from being deteriorated by discharge. Further, by setting the thickness to 180 μm or less, the distance between the discharge at the scan electrode and the phosphor can be reduced, and sufficient luminance can be obtained.

  The height of the partition wall is preferably higher than the height of the auxiliary partition wall, and the difference between the height of the partition wall and the height of the auxiliary partition wall is preferably 2 to 40 μm, more preferably 3 to 30 μm. When the difference between the height of the partition wall and the height of the auxiliary partition wall is less than 2 μm, the exhaust path of the gas component remaining in the cell surrounded by the front plate, the back plate, the partition wall, and the auxiliary partition wall when sealing and exhausting the panel Therefore, impure gas tends to remain, and as a result, panel characteristics may be adversely affected. On the other hand, when the thickness exceeds 40 μm, the charge accumulated in the cell due to the voltage application tends to easily escape to the adjacent cell in the vertical direction, and the function as an auxiliary partition tends not to be performed.

  The positions and pitches for forming the auxiliary barrier ribs are preferably formed at positions where the pixels are divided when the plasma display is combined with the front plate from the viewpoint of gas discharge and light emission efficiency of the phosphor layer.

  Next, the formation method of the partition and the auxiliary partition in this invention is demonstrated. The partition walls and the auxiliary partition walls are known using screen paste, sand blasting, photosensitive paste method (photolithography method), mold transfer method, lift-off method, etc., using paste made of insulating inorganic and organic components on the substrate. It is formed by forming a pattern with this technique and baking it, but for the reason that high shape control and uniformity can be obtained, the photosensitive paste is applied to the substrate and dried to form a photosensitive paste film. The so-called photosensitive paste method (photolithographic method) in which exposure and development are performed through a photomask is preferably applied in the present invention.

  Hereinafter, the partition formation by the photosensitive paste method preferably applied in the present invention will be described in detail.

  The photosensitive paste used in the present invention contains inorganic fine particles and a photosensitive organic component as main components, and if necessary, a photopolymerization initiator, a light absorber, a sensitizer, an organic solvent, a sensitization aid, and a polymerization inhibitor. contains.

  As the inorganic fine particles of the photosensitive paste, glass, ceramic (alumina, cordierite, etc.) and the like can be used. In particular, glass or ceramics containing silicon oxide, boron oxide, or aluminum oxide as an essential component is preferable.

The particle diameter of the inorganic fine particles is selected in consideration of the shape of the partition wall pattern to be produced, but the volume average particle diameter is preferably 1 to 10 μm, and more preferably 1 to 5 μm. By setting the volume average particle diameter to 10 μm or less, it is possible to prevent surface irregularities from occurring. Moreover, the viscosity adjustment of a paste can be made easy by setting it as 1 micrometer or more. Furthermore, it is particularly preferable in the pattern formation to use glass fine particles having a specific surface area of 0.2 to ³ m ² / g.

Since the partition walls and the auxiliary partition walls are preferably patterned on a glass substrate having a low heat softening point, inorganic particles containing 60% by mass or more of low melting glass particles having a thermal softening temperature of 350 to 600 ° C. are used as the inorganic particles. It is preferable. Moreover, by adding a filler component composed of high melting point glass fine particles or ceramic fine particles having a heat softening temperature of 600 ° C. or more, the shrinkage rate during firing can be suppressed, but the amount is equal to the total amount of inorganic fine particles. The amount is preferably 40% by mass or less. The low-melting glass fine particles have a linear expansion coefficient of 50 × 10 ⁻⁷ ° C. ^{−1 to} 90 × 10 ⁻⁷ ° C. ¹ , or 60 × 10 ⁻⁷ ° C. so as not to cause warping of the glass substrate during firing. It is preferable to use low melting point glass fine particles of ^{−1 to} 90 × 10 ⁻⁷ ° C. ⁻¹ .

  As the low-melting glass fine particles, glass containing silicon and / or boron oxide is preferably used.

  The silicon oxide is preferably blended in the range of 3 to 60% by mass. By setting the content to 3% by mass or more, the denseness, strength and stability of the glass layer are improved, and the thermal expansion coefficient is set within a desired range to prevent the problem of warpage due to the difference in thermal expansion coefficient with the glass substrate. be able to. Moreover, by setting it as 60 mass% or less, there exists an advantage that a thermal softening point becomes low and baking to a glass substrate is attained.

  Boron oxide can improve electrical, mechanical, and thermal characteristics such as electrical insulation, strength, thermal expansion coefficient, and denseness of the insulating layer by blending in the range of 5 to 50% by mass. The stability of glass can be maintained by setting it as 50 mass% or less.

Furthermore, by containing at least one of bismuth oxide, lead oxide, and zinc oxide in a total amount of 5 to 50% by mass, a glass paste having temperature characteristics suitable for patterning on a glass substrate can be obtained. it can. In particular, when glass fine particles containing 5 to 50% by mass of bismuth oxide are used, advantages such as a long pot life of the paste can be obtained. As the bismuth-based glass fine particles, glass powder containing the following composition is preferably used.
Bismuth oxide: 10 to 40% by mass
Silicon oxide: 3-50 mass%
Boron oxide: 10 to 40% by mass
Barium oxide: 8-20% by mass
Aluminum oxide: 10-30% by mass
Moreover, you may use the glass fine particle which contains 3-20 mass% of at least 1 sort (s) among lithium oxide, sodium oxide, and potassium oxide. By adding the alkali metal oxide in an amount of 20% by mass or less, preferably 15% by mass or less, the stability of the paste can be improved. Of the above three types of alkali metal oxides, lithium oxide is particularly preferred from the viewpoint of paste stability. As the lithium glass fine particles, for example, glass powder containing the following composition is preferably used.
Lithium oxide: 2 to 15% by mass
Silicon oxide: 15-50 mass%
Boron oxide: 15-40% by mass
Barium oxide: 2 to 15% by mass
Aluminum oxide: 6-25% by mass
In addition, if glass fine particles containing both metal oxides such as lead oxide, bismuth oxide and zinc oxide and alkali metal oxides such as lithium oxide, sodium oxide and potassium oxide are used, with a lower alkali content, The thermal softening temperature and linear expansion coefficient can be easily controlled.

  Also, workability is improved by adding aluminum oxide, barium oxide, calcium oxide, magnesium oxide, titanium oxide, zinc oxide, zirconium oxide, etc., especially aluminum oxide, barium oxide, zinc oxide, etc. to the glass fine particles. However, from the viewpoint of the thermal softening point and the thermal expansion coefficient, the content is preferably 40% by mass or less, more preferably 25% by mass or less.

  The photosensitive organic component preferably contains at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer.

  The photosensitive monomer is a compound containing a carbon-carbon unsaturated bond. Specific examples thereof include acrylics such as monofunctional and polyfunctional (meth) acrylates, vinyl compounds, and allyl compounds. It is preferable to use a system monomer. These can be used alone or in combination of two or more.

  As the photosensitive oligomer and photosensitive polymer, an oligomer or polymer obtained by polymerizing at least one of monomers having a carbon-carbon double bond can be used. Preferably, an oligomer or a polymer obtained by polymerizing at least one of the acrylic monomers can be used. In the polymerization, the monomer can be copolymerized with another photosensitive monomer so that the content of the monomer is 10% by mass or more, more preferably 35% by mass or more. By copolymerizing an unsaturated acid such as an unsaturated carboxylic acid with a polymer or oligomer, the developability after exposure can be improved. 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 acid value (AV) of the polymer or oligomer having an acidic group such as a carboxyl group in the side chain thus obtained is preferably in the range of 50 to 180, and more preferably in the range of 70 to 140. By adding a photoreactive group to the side chain or molecular end of the polymer or oligomer shown above, it can be used as a photosensitive polymer or photosensitive oligomer having photosensitivity. Preferred photoreactive groups are those having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, an acrylic group, and a methacryl group.

  Specific examples of the photopolymerization initiator include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamino) benzophenone, 4,4-bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4- Examples include benzoyl-4-methylphenyl ketone, dibenzyl ketone, fluorenone, 2,3-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, and the like. One or more of these can be used. The photopolymerization initiator is preferably added in a range of 0.05 to 10% by mass, and more preferably in a range of 0.1 to 5% by mass with respect to the photosensitive component. If the amount of the polymerization initiator is too small, the photosensitivity tends to decrease, and if the amount of the photopolymerization initiator is too large, the residual ratio of the exposed portion tends to be too small.

  It is also effective to add a light absorber. By adding a compound having a high absorption effect of ultraviolet light or visible light, a high aspect ratio, high definition, and high resolution can be obtained. As the light absorber, those composed of organic dyes are preferably used. Specifically, azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, anthraquinone dyes, benzophenone dyes, diphenylcyanoacrylate dyes are used. Dyes, triazine dyes, p-aminobenzoic acid dyes, and the like can be used. Since organic dye does not remain in the insulating film after baking, it is preferable because the deterioration of the insulating film characteristics due to the light absorber can be reduced. Among these, azo dyes and benzophenone dyes are preferable. The addition amount of the organic dye is preferably 0.05 to 5% by mass, and more preferably 0.05 to 1% by mass. When the addition amount is less than the above range, the effect of adding the light absorber tends to be reduced, and when it is more than the above range, the insulating film characteristics after firing tend to be lowered.

  A sensitizer is added in order to improve sensitivity. Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone, 2,3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone, and the like. Is mentioned. One or more of these can be used. When adding a sensitizer to a photosensitive paste, the addition amount is 0.05-10 mass% normally with respect to the photosensitive component, More preferably, it is 0.1-10 mass%. When the amount of the sensitizer is less than the above range, the effect of improving the photosensitivity tends not to be exhibited, and when the amount of the sensitizer is larger than the above range, the residual ratio of the exposed portion tends to be small.

  Examples of the organic solvent include methyl cellosolve, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether acetate, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, and γ-butyllactone. , N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, bromobenzene, chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid and the like, and one or more of these An organic solvent mixture is used.

  The photosensitive paste is usually prepared by mixing the above-mentioned inorganic fine particles and organic components so as to have a predetermined composition, and then uniformly mixing and dispersing them with a three roller or kneader. Next, a photosensitive paste is applied, dried, exposed, developed, and the like.

  In these series of forming steps, a screen printing method, a bar coater, a roll coater, a die coater, a blade coater, or the like can be used as a method for applying the photosensitive paste. The coating thickness can be adjusted by selecting the number of coatings, screen mesh, and paste viscosity.

  In addition, a drying oven, a hot plate, an IR furnace, or the like can be used for drying after application.

Examples of the active light source used for exposure include visible light, near ultraviolet light, ultraviolet light, electron beam, X-ray, and laser light. Among these, ultraviolet rays are most preferable, and as the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a halogen lamp, or a germicidal lamp can be used. Among these, an ultrahigh pressure mercury lamp is suitable. Exposure conditions vary depending on the coating thickness, but exposure is performed for 0.1 to 10 minutes using an ultrahigh pressure mercury lamp with an output of 1 to 100 mW / cm ² .

  Here, the distance between the photomask and the surface of the photosensitive paste coating film (hereinafter referred to as the gap amount) is preferably adjusted to 50 to 500 μm, more preferably 70 to 400 μm. By setting the gap amount to 50 μm or more, more preferably 70 μm or more, contact between the photosensitive paste coating film and the photomask can be prevented, and destruction or contamination of both can be prevented. Moreover, sharp patterning is attained by setting it as 500 micrometers or less, More preferably, it is 400 micrometers or less.

  Development is performed using the difference in solubility in the developer between the exposed portion and the non-exposed portion. Development can be performed by a dipping method, a spray method, a brush method, or the like.

  Developer can dissolve organic components in the photosensitive paste, that is, photosensitive organic components before exposure in the case of negative photosensitive paste, and organic components after exposure in the case of positive photosensitive paste. Is used. When a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, it can be developed with an alkaline aqueous solution. As the alkaline aqueous solution, an inorganic alkaline aqueous solution such as sodium hydroxide, sodium carbonate, sodium carbonate aqueous solution, calcium hydroxide aqueous solution or the like can be used. However, the use of the organic alkaline aqueous solution facilitates removal of alkali components during firing. preferable. As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, and diethanolamine. The density | concentration of aqueous alkali solution is 0.01-10 mass% normally, More preferably, it is 0.1-5 mass%. If the alkali concentration is too low, the soluble portion tends not to be removed. If the alkali concentration is too high, the pattern portion tends to be peeled off or the insoluble portion tends to be corroded. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Next, the partition / auxiliary partition pattern obtained by development is fired in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a roller hearth-type continuous firing furnace can be used. The firing temperature is preferably 400 to 800 ° C. In the case where the partition wall is directly formed on the glass substrate, it is preferable to perform baking while maintaining the temperature at 450 to 620 ° C. for 10 to 60 minutes.

  Next, a phosphor layer that emits light of each color of red (R), green (G), and blue (B) is formed between barrier ribs formed in a direction parallel to a predetermined address electrode. The phosphor layer can be formed by applying a phosphor paste containing phosphor powder, an organic binder, and an organic solvent as main components between predetermined partitions, drying, and firing as necessary.

  As a method of applying the phosphor paste between predetermined partitions, a screen printing method in which a pattern is printed using a screen printing plate, a dispenser method in which the phosphor paste is discharged from the tip of a discharge nozzle, or a phosphor paste The phosphor paste of each color can be applied to a predetermined place by the above-described photosensitive paste method using the photosensitive organic component, but the screen printing method and the dispenser method are preferably applied in the present invention for cost reasons. .

When the thickness of the red phosphor layer is Tr (μm), the thickness of the green phosphor layer is Tg (μm), and the thickness of the blue phosphor layer is Tb (μm), the expressions (2) and (3) are satisfied. It is preferable.
10 ≦ Tr ≦ Tb ≦ 50 (2),
10 ≦ Tg ≦ Tb ≦ 50 (3)
That is, a plasma display having a better color balance (high color temperature) can be produced by making the thickness of blue with low emission luminance thicker than green and red. A sufficient luminance can be obtained by setting the thickness of the phosphor layer to 10 μm or more. Further, by setting the thickness to 50 μm or less, a wide discharge space can be obtained and high luminance can be obtained. The thickness of the phosphor layer in this case is measured as the thickness after firing at the midpoint between the adjacent partition walls. That is, it is measured as the thickness of the phosphor layer formed at the bottom of the discharge space (in the pixel cell surrounded by the barrier ribs and the auxiliary barrier ribs).

  By baking the coated phosphor layer at 400 to 550 ° C. as necessary, the back plate for plasma display of the present invention can be produced.

  Using this back plate for plasma display, after sealing with the front plate, the discharge circuit composed of helium, neon, xenon, etc. is sealed in the space formed between the front and back substrates, and the drive circuit is installed. Can produce plasma displays. The front plate is a member in which a transparent electrode, a bus electrode, a dielectric, and a protective film (MgO) are formed on a substrate in a predetermined pattern. You may form a color filter layer in the part corresponding to the RGB each color phosphor layer formed on the back plate. Further, a black stripe may be formed in order to improve contrast.

  Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to this.

  The evaluation method will be described.

<Defect inspection evaluation>
The substrate on which the address electrode was formed was inspected for defects using an image inspection machine (Neptune 9000, manufactured by Vu Technology). The case where no defect was detected falsely was marked with ◎, and the case where a false detection occurred was marked with ×.

<Display unevenness evaluation>
The produced front plate and back plate were sealed with sealing glass, and Ne gas containing Xe 12% was sealed so as to have an internal gas pressure of 66500 Pa. Further, a plasma display panel was manufactured by mounting a drive circuit. A scan voltage of 120 V, a sustain voltage of 180 V, and a data voltage of 70 V are applied to the scan electrode, the sustain electrode, and the address electrode of the obtained plasma display panel, respectively, and a white still image is lit on the entire surface. Measured by MCPD-7000 manufactured by Denshi Co. Display unevenness was evaluated according to the following evaluation criteria.
In-plane brightness variation is less than ± 5%:
In-plane brightness variation is ± 5 to ± 10%: ○
In-plane brightness variation is greater than ± 10%: ×
<Evaluation of power consumption>
A scan voltage of 120 V, a sustain voltage of 180 V, and a data voltage of 70 V are applied to the plasma display panel used for the display unevenness evaluation to light a white still image on the entire surface, power consumption is measured, and the plasma display panel of Example 1 is measured. Relative comparison was performed with power consumption as 1.

<Discharge abnormality evaluation>
A scan voltage of 120 V, a sustain voltage of 170 V, and a data voltage of 60 V were applied to the plasma display panel used for the display unevenness evaluation to light a white still image on the entire surface, and the number of unlit cells was counted. The discharge abnormality was evaluated according to the following evaluation criteria.
0 unlit cells: ◎
1-3 unlit cells: ○
4 or more unlit cells: ×
(Examples 1-4, Comparative Examples 1-3)
A 42-inch AC (alternating current) plasma display panel was fabricated and evaluated. The manufacturing method will be described in order.

Example 1
As a glass substrate, PD-200 (manufactured by Asahi Glass Co., Ltd.) having a size of 590 × 964 × 2.8 mm and 42 inches was used. On this substrate, as an address electrode, 70 parts by weight of silver powder having an average particle diameter of 2.0 μm, Bi ₂ O ₃ / SiO ₂ / Al ₂ O ₃ / B ₂ O ₃ = 69/24/4/3 (mass 2 parts by weight of glass powder having an average particle size of 2.2 μm, 8 parts by weight of a copolymer of acrylic acid, methyl methacrylate and styrene, 7 parts by weight of trimethylolpropane triacrylate, 3 parts by weight of benzophenone, butyl carbitol A photosensitive silver paste consisting of 7 parts by weight of acrylate and 3 parts by weight of benzyl alcohol was applied to a thickness of 10 μm using a screen printer, and then dried at 120 ° C. for 10 minutes in a clean oven to form a coating film. A gap between the formed coating film and a photomask having a predetermined pattern was 150 μm, and exposure was performed at an exposure amount of 500 mJ. The exposed substrate formed as described above was developed with a 0.5 mass% ethanolamine aqueous solution to form an address electrode pattern. The address electrode was formed so as to satisfy the following values. A schematic diagram is shown in FIGS.
Pitch: 240 μm
Number of cells in part A row direction: 650
Maximum electrode width in cell: 90 μm
Minimum electrode width in cell: 70 μm
Number of cells in B part row direction: 29
Maximum electrode width in cell: 93 to 180 μm (93 μm for the cell closest to the A portion, 3 μm thicker toward the C portion, and 180 μm for the cell closest to the C portion)
Minimum electrode width in cell: 70 μm
Number of cells in row C: 30
Maximum electrode width in cell: 180 μm
Minimum electrode width in cell: 70 μm
The prepared address electrode substrate was subjected to defect inspection using an image inspection machine (Neptune 9000, manufactured by Buoy Technology Co., Ltd.).

Low melting point glass fine particles having a volume average particle diameter of 2 μm, comprising Bi ₂ O ₃ / SiO ₂ / Al ₂ O ₃ / ZnO / B ₂ O ₃ = 78/14/3/3/2 (mass%) on this substrate. A dielectric paste consisting of 60 parts by weight, 10 parts by weight of titanium oxide powder having an average particle size of 0.3 μm, 15 parts by weight of ethyl cellulose, and 15 parts by weight of terpineol was applied and baked at 580 ° C. to form a dielectric having a thickness of 10 μm. A body layer was formed.

  The photosensitive paste for partition formation used the following composition.

The following components were blended and used.
Glass powder: Bi ₂ O ₃ / SiO ₂ / Al ₂ O ₃ / ZnO / B ₂ O ₃ = 82/5/3/5/3/2 (mass%), glass powder having an average particle diameter of 2 μm 67 weight Part filler: Titanium oxide having an average particle size of 0.2 μm 3 parts by weight Polymer: “Cyclomer” P (ACA250, manufactured by Daicel Chemical Industries) 10 parts by weight Organic solvent (1): Benzyl alcohol 4 parts by weight Organic solvent (2) : Butyl carbitol acetate 3 parts by weight Monomer: Dipentaerythritol hexaacrylate 8 parts by weight Photopolymerization initiator: Benzophenone 3 parts by weight Antioxidant: 1,6-hexanediol-bis [(3,5-di-t-butyl -4-hydroxyphenyl) propionate] 1 part by weight Organic dye: Basic Blue 26 0.01 part by weight thixotropic agent: N, N′-12 -Butyrylenediamine hydroxystearate: 0.5 part by weight Surfactant: Polyoxyethylene cetyl ether: 0.49 part by weight.

  The partition wall forming photosensitive paste was applied to a thickness of 250 μm using a die coater, and then dried in a clean oven at 100 ° C. for 40 minutes to form a coating film. Further, the barrier rib forming photosensitive paste was applied to a thickness of 50 μm using a die coater, and then dried at 100 ° C. for 30 minutes in a clean oven to form a coating film. A gap between the formed coating film and a predetermined photomask was set to 150 μm with respect to the formed coating film, and exposure of the partition walls and the auxiliary partition walls was performed at an exposure amount of 300 mJ. The partition wall width was 50 μm, the pitch was 240 μm, the auxiliary partition wall width was 50 μm, and the pitch was 700 μm.

  The exposed substrate formed as described above was developed with a 0.5% by mass aqueous ethanolamine solution to form a partition pattern. The substrate on which pattern formation was completed was baked at 560 ° C. for 15 minutes.

  Each color phosphor paste was applied to the formed barrier ribs using a screen printing method and baked (500 ° C., 30 minutes) to form phosphor layers on the side and bottom portions of the barrier ribs.

  Next, the front plate was produced by the following steps. First, a PD-200 (manufactured by Asahi Glass Co., Ltd.) of 590 × 964 × 2.8 mm having a size of 590 × 964 × 2.8 mm was used, ITO was formed on this glass substrate by sputtering, resist was applied, exposure and development A transparent electrode having a thickness of 0.1 μm and a line width of 200 μm was formed by the treatment and the etching treatment. Further, a bus electrode having a thickness of 5 μm after firing was formed by photolithography using a photosensitive silver paste made of black silver powder. Electrodes with a pitch of 375 μm and a line width of 100 μm were produced.

  Next, a glass paste obtained by kneading 70 parts by weight of low melting point glass powder containing 75% by weight of lead oxide, 20 parts by weight of ethyl cellulose, and 10 parts by weight of terpineol was screen-printed to obtain a bus electrode for the display part. After coating with a thickness of 50 μm so as to be covered, firing was performed at 570 ° C. for 15 minutes to form a front dielectric.

  A front plate was produced by forming a 0.5 μm thick magnesium oxide layer as a protective film by electron beam evaporation on the substrate on which the dielectric was formed.

  The obtained front glass substrate was bonded and sealed to the rear glass substrate, and then a discharge gas was sealed, and a driving circuit was joined to produce a plasma display.

(Example 2)
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes were formed as follows.
Pitch: 240 μm
Number of cells in row A: 680
Maximum electrode width in cell: 90 μm
Minimum electrode width in cell: 70 μm
Number of cells in row B row: 14
Maximum electrode width in the cell: 96 to 174 μm (96 μm for the cell closest to the A portion, thicker by 6 μm toward the C portion, and 174 μm for the cell closest to the C portion)
Minimum electrode width in cell: 70 μm
Number of cells in row C: 30
Maximum electrode width in cell: 180 μm
Minimum electrode width in cell: 70 μm
(Example 3)
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes were formed as follows.
Pitch: 240 μm
Number of cells in row A: 700
Maximum electrode width in cell: 75 μm
Minimum electrode width in cell: 70 μm
Number of cells in row B row: 4
Maximum electrode width in the cell: 78 to 87 μm (78 μm for the cell closest to the A portion, thicker by 3 μm toward the C portion, and 87 μm for the cell closest to the C portion)
Minimum electrode width in cell: 70 μm
Number of cells in row C: 30
Maximum electrode width in cell: 90 μm
Minimum electrode width in cell: 70 μm
Example 4
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes were formed as follows.
Pitch: 240 μm
Number of cells in row A: 608
Maximum electrode width in cell: 75 μm
Minimum electrode width in cell: 70 μm
Number of cells in row B: 50
Maximum electrode width in cell: 78 to 225 μm (78 μm for the cell closest to the A portion, 3 μm thicker toward the C portion, and 225 μm for the cell closest to the C portion)
Minimum electrode width in cell: 70 μm
Number of cells in row C: 30
Maximum electrode width in cell: 230 μm
Minimum electrode width in cell: 70 μm
(Comparative Example 1)
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes have a stripe shape with a constant pitch of 240 μm and a width of 80 μm in the display area.

(Comparative Example 2)
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes have a stripe shape with a constant pitch of 240 μm and a width of 200 μm in the display area.

(Comparative Example 3)
A plasma display panel was produced in the same manner as in Example 1. However, the address electrodes were formed as follows.
Pitch: 240 μm
Number of cells in row A: 708
Maximum electrode width in cell: 75 μm
Minimum electrode width in cell: 70 μm
Number of cells in B section row direction: 0
Number of cells in row C: 30
Maximum electrode width in cell: 230 μm
Minimum electrode width in cell: 70 μm

  The evaluation results of Examples 1 to 4 and Comparative Examples 1 to 3 are shown in Table 1. In each of Examples 1 to 4, plasma display panels were obtained that were not erroneously detected by defect inspection, had good display quality, and did not significantly increase power consumption. On the other hand, the display quality is not good in Comparative Example 1, and the power consumption is increased in Comparative Example 2. In Comparative Example 3, not only the display quality was not good, but also erroneous detection of defects occurred.

It is a schematic diagram of the plasma display panel of the present invention. It is a schematic diagram of the backplate used for the plasma display panel of this invention. It is a schematic diagram of the backplate used for the plasma display panel of this invention. It is a schematic diagram of the backplate used for the plasma display panel of this invention. It is a schematic diagram of a plasma display panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Partition 2 Auxiliary partition 3 Address electrode 4 Scan electrode 5 Sustain electrode 6 Cell 7 Pixel 8 In-cell maximum electrode width 9 Cell boundary line 10 Display area 11 In-cell minimum electrode width 12 Glass substrate 13 Black stripe 14 Dielectric layer 15 Protection Layer (MgO layer)
16 Glass substrate 17 Dielectric layer 18 Phosphor (R)
19 Phosphor (G)
20 Phosphor (B)

Claims (3)

A display electrode, a front plate having a dielectric layer, and an address electrode, a dielectric layer, and a rear plate having a partition wall are arranged to face each other.
The barrier ribs define discharge cells,
The width of the address electrode is different within the region of the discharge cell, and the width of the address electrode is the maximum (maximum electrode width in the cell) at the center of the discharge cell.
In the back plate surface, the maximum electrode width in the cell is different,
In the end portion of the back plate than the center portion of the back plate , the maximum electrode width in the cell is larger,
The difference between the maximum electrode widths in the adjacent discharge cells is 10 μm or less,
Plasma display panel. 2. The plasma display panel according to claim 1, wherein a difference between a maximum value and a minimum value of the maximum electrode width in the cell in ten adjacent and continuous discharge cells is 50 μm or less. 2. The plasma display panel according to claim 1 , wherein a difference between the maximum value of the width of the address electrode and the minimum value of the width in the discharge cell region is 11 to 150 μm .

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