JP2013149518A - Manufacturing method of plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method to prevent generation of non-core cissing in which MgO powder dispersed over a protection film is repelled in a process to apply prepared ink with a slit coater.SOLUTION: In a manufacturing method of a plasma display panel formed with an electrode, a dielectric layer and a protection layer over a substrate, the protection layer is formed by the steps of: (i) forming a first protection layer over the dielectric layer which is formed over the substrate using sputtering method or deposition method; (ii) forming an MgO raw material layer by applying MgO raw material over the first protection layer using slit coater method; and (iii) forming a second protection layer by drying the MgO raw material layer. The MgO raw material includes MgO powder and two or more kinds of solvents and any of the two kinds or more solvents is a water-soluble organic solvent having one or more hydroxy groups.

Description

  The present invention relates to a method for manufacturing a plasma display panel, which includes a step of spraying magnesium oxide crystal powder on a protective layer.

  As a display device for displaying a high-definition television image on a large screen, there is an increasing expectation for a display device using a plasma display panel (hereinafter also referred to as PDP).

  The PDP has a structure in which a front plate on the front side and a back plate on the back side as viewed from the viewer of an image are arranged to face each other and their peripheral portions are sealed with a sealing member. A discharge gas such as neon and xenon is sealed in a discharge space formed between the front plate and the back plate. The front plate includes a display electrode formed of a scan electrode and a sustain electrode formed on one surface of the glass substrate, and a dielectric layer and a protective layer that cover these electrodes. The back plate includes a plurality of address electrodes formed in a stripe shape in a direction orthogonal to the display electrodes on the glass substrate, a base dielectric layer that covers these address electrodes, and a partition that partitions the discharge space for each address electrode And red, green, and blue phosphor layers formed on the side surfaces of the barrier ribs and the underlying dielectric layer.

  The display electrodes and the address electrodes are orthogonal to each other, and the intersections form discharge cells. These discharge cells are arranged in a matrix, and three discharge cells having red, green, and blue phosphor layers are pixels for color display. In such a PDP, a predetermined voltage is sequentially applied between the scan electrode and the address electrode and between the scan electrode and the sustain electrode to generate gas discharge. A phosphor layer is excited by ultraviolet rays generated by such gas discharge to emit visible light, thereby realizing color image display.

  As a protective layer of such a PDP, in order to protect the dielectric layer from ion collisions caused by discharge and to promote phosphor emission by secondary electron emission, a “thin film layer having a wall charge holding function” and “initial stage” In some cases, a protective layer having a two-layer structure of “a crystal layer having an electron emission function” is employed. As a raw material for such a protective layer, generally, magnesium oxide (MgO) having excellent sputtering resistance and a high secondary electron emission coefficient is used.

  In Patent Document 1, an evaporation method or the like is used for forming the MgO thin film layer, while a slit coater method is used for forming the MgO crystal layer. In particular, in the first embodiment of Patent Document 1, MgO single crystal powder having a diameter of 0.5 to 10 μm is dispersed in a mixed solvent composed of 3-methoxy-3-methyl-1-butanol and α-terpineol. Therefore, the slit coater ink is prepared.

  When the MgO crystal layer is formed using the slit coater method with the ink produced in the first embodiment of Patent Document 1, as shown in FIG. 4, “MgO crystal powder is formed on the MgO thin film layer. There may occur a phenomenon (hereinafter referred to as a “repelling phenomenon”) in which a “non-existing region 53” or a “region 53 having a lower MgO crystal powder coverage than the surrounding region 52” is formed. FIG. 4 is a perspective view schematically showing a conventional “repelling phenomenon”.

  The “repellency phenomenon” is considered to be caused by the convex portion 51 of the MgO thin film layer. The convex portion 51 is generated during vapor deposition of (A) dielectric protrusion and (B) MgO thin film layer. MgO splash caused by MgO splash, (C) environmental foreign matter mixed in the MgO thin film layer forming process, and the like, may occur accidentally or unavoidably in the manufacturing process of the PDP front plate.

JP 2009-295372 A

  As a conventional method, when the MgO crystal layer is formed using the slit coater method with the ink prepared in the first embodiment of Patent Document 1, as shown in FIG. Phenomenon (hereinafter referred to as “nuclear-free repelling phenomenon”) in which “region 53 where no MgO crystal powder exists” or “region 53 where the coverage of MgO crystal powder is lower than the surrounding region” occurs. Sometimes. When this phenomenon occurs, there is a problem that the uniformity of the coverage of the MgO crystal powder on the MgO thin film layer is reduced, and it becomes difficult to suppress the discharge delay and make the discharge probability uniform.

  Note that the “repelling phenomenon” described in Patent Document 1 and the above “nuclear-free repelling phenomenon” are similar but different. The “nuclear repelling phenomenon” occurs even without the presence of the convex portion 51.

  The present invention has been made in view of such circumstances. That is, an object of the present invention is to provide a method and an ink for suppressing the “nuclear-free repelling phenomenon” in the slit coater method.

  In order to solve the above-described problems, the present invention provides a method for manufacturing a PDP in which an electrode, a dielectric layer, and a protective layer are formed on a substrate, and the formation of the protective layer is (i) formed on the substrate. Forming a first protective layer on the formed dielectric layer by sputtering or vapor deposition, and (ii) forming an MgO raw material layer by applying an MgO raw material on the first protective layer by a slit coater method. And (iii) drying the MgO raw material layer to form a second protective layer, wherein the MgO raw material contains MgO powder and two or more solvents, and any of the two or more solvents are A water-soluble organic solvent having one or more hydroxy groups.

  Here, the two or more types of solvents include three types of solvent A, solvent B, and solvent C, and the ratio of the sum of solvent B and solvent C to the total amount of solvent is 3.5% by mass or more. It is desirable.

  The solvent A is an alcoholic organic solvent, and the solvents B and C are preferably glycol ether organic solvents or glycol ether derivatives.

  In the manufacturing method of the present invention, the “nuclear-free repelling phenomenon” of the MgO raw material can be suppressed when forming the second protective layer. In other words, an MgO crystal layer having a uniform in-plane coverage can be formed, and the discharge delay can be suppressed and the discharge probability can be made uniform. As a result, it is possible to obtain a PDP having good discharge characteristics with no selection failure.

The perspective view which shows the structure of PDP typically Sectional drawing which represented the front plate of PDP obtained with the manufacturing method of this invention typically Perspective view schematically showing the mode of repelling without a nucleus Perspective view schematically showing the mode of the repelling phenomenon

  Embodiments of the present invention will be described below with reference to the drawings. Below, the manufacturing method of PDP of this invention is demonstrated in detail.

[Configuration of PDP]
First, the PDP finally obtained through the manufacturing method of the present invention will be briefly described. FIG. 1 is a diagram schematically showing a configuration of a PDP by a cross-sectional perspective view.

  In the front plate 1 of the PDP 100, a plurality of display electrodes 11 including scan electrodes 12 and sustain electrodes 13 are formed on a smooth, transparent and insulating substrate 10 (for example, a glass substrate), and covers the display electrodes 11. A dielectric layer 15 is formed as described above, and a protective layer 16 is further formed on the dielectric layer 15. Scan electrode 12 and sustain electrode 13 are each composed of a transparent electrode and a bus electrode made of Ag or the like electrically connected to the transparent electrode. A light shielding layer 14 can also be formed on the substrate 10.

  In the back plate 2 disposed to face the front plate 1, a plurality of address electrodes 21 are formed on an insulating substrate 20, and a dielectric layer 22 is formed so as to cover the address electrodes 21. A partition wall 23 is provided at a position corresponding to the space between the address electrodes 21 on the dielectric layer 22. Between the adjacent partition walls 23 on the surface of the dielectric layer 22, fluorescence of red, green, and blue colors is provided. Each body layer 25 is provided.

  The front plate 1 and the back plate 2 are arranged to face each other with the partition wall 23 therebetween so that the display electrodes 11 and the address electrodes 21 are orthogonal to each other and the discharge space 30 is formed. The discharge space 30 is filled with a rare gas such as helium, neon, argon or xenon as a discharge gas. In the PDP 100 having such a configuration, the discharge space 30 that is partitioned by the partition wall 23 and intersects the display electrode 11 and the address electrode 21 functions as the discharge cell 32.

[General manufacturing method of PDP]
Next, a typical manufacturing method of such a PDP 100 will be briefly described. The manufacture of the PDP 100 is divided into a front plate 1 forming step and a back plate 2 forming step. First, in the step of forming the front plate 1, the display electrode 11 is formed on the glass substrate 10 by forming a transparent electrode by, for example, a sputtering method and forming a bus electrode by a firing method or the like. Next, a dielectric material is applied on the glass substrate 10 so as to cover the display electrodes 11 and heat-treated to form the dielectric layer 15. Next, a protective layer 16 is formed on the dielectric layer 15 by forming a film made of MgO or the like by the method described above or later, and the front plate 1 is obtained.

  In the step of forming the back plate 2, the address electrode 21 is formed on the glass substrate 20 by, for example, a firing method, and a dielectric material is applied thereon to form the dielectric layer 22. Next, the barrier ribs 23 made of low melting point glass are formed in a predetermined pattern, and the phosphor layer 25 is formed by applying a phosphor material between the barrier ribs 23 and baking it. Next, for example, a low melting point frit glass material is applied to the peripheral portion of the substrate and baked to form a sealing member (not shown in FIG. 1), whereby the back plate 2 is obtained.

  The obtained front plate 1 and back plate 2 are aligned so as to face each other, and the front plate 1 and the back plate 2 are joined in an airtight manner by heating in a fixed state and softening the sealing member. A so-called panel sealing step is performed. Subsequently, after performing a so-called exhaust baking process in which the gas in the discharge space 30 is exhausted while being heated, the discharge gas is enclosed in the discharge space 30 to complete the PDP 100.

[Production method of the present invention]
The production method of the present invention relates to the production of a front plate, particularly the production of a protective layer formed on the front plate, in producing the above-mentioned PDP.

  An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 2 is a cross-sectional view schematically showing a front plate of a PDP obtained by the manufacturing method of the present invention. First, in carrying out the present invention, a substrate on which an electrode and a dielectric layer are formed is prepared. More specifically, a “glass substrate on which a display electrode and a dielectric layer are formed” is prepared. Therefore, first, a substrate in which the display electrode 11 including the scan electrode 12 and the sustain electrode 13 is formed on the substrate 10 is prepared. The substrate 10 is preferably an insulating substrate made of soda lime glass, high strain point glass, or various ceramics, and preferably has a thickness of about 1.0 mm to 3 mm. Transparent electrodes 12a and 13a (thickness of about 50 nm to 500 nm) made of ITO or the like are formed on the scanning electrode 12 and the sustain electrode 13 of the display electrode 11, respectively, and the resistance value of the display electrode is formed on the transparent electrode. The bus electrodes 12b and 13b (thickness of about 1 μm to 8 μm) containing silver are formed (see FIG. 2). Therefore, after forming the transparent electrode by a thin film process or the like, the transparent electrode is formed through a bus electrode firing process or the like. In particular, when forming the bus electrode, first, a conductive paste mainly composed of silver is formed in a stripe shape by a screen printing method. In addition, the bus electrode is formed in a stripe shape by applying a photosensitive paste mainly composed of silver by a die coating method or a printing method, drying at 100 ° C. to 200 ° C., and then patterning by a photolithography method that exposes and develops. You may form in. Further, it may be formed by a dispensing method or an ink jet method. And finally, after subjecting to drying, a bus electrode is obtained by subjecting to baking at 400 ° C. to 600 ° C. On the transparent electrode, a metal electrode made of a metal such as Al, Cu or Cr or a laminate such as Cr / Cu / Cr may be formed.

Subsequent to the formation of the display electrode 11, a dielectric layer 15 is formed. The dielectric layer 15 can be obtained by a firing method or a sol-gel method used in general production of a PDP front plate. For example, a dielectric raw material paste formed by mixing glass powder containing SiO ₂ , B ₂ O ₃ , ZnO, Bi ₂ O ₃ , an organic solvent, and a binder resin is applied by screen printing, and then subjected to heat treatment. Thus, a dielectric layer can be formed. The thickness of the dielectric layer 15 is preferably about 5 to 30 μm, more preferably about 10 to 20 μm. Examples of the organic solvent include alcohols (for example, isopropyl alcohol) and ketones (for example, methyl isobutyl ketone), and examples of the binder resin include cellulose resins and acrylic resins.

  Subsequent to the formation of the dielectric layer 15, a protective layer is formed. Therefore, step (i) of the manufacturing method of the present invention is performed. In other words, the first protective layer 16a is formed on the dielectric layer by sputtering (sputtering) or vapor deposition. Preferably, the first protective layer 16a (that is, MgO thin film layer) containing magnesium oxide (MgO) is formed. The thickness of the first protective layer to be formed is preferably about 0.1 to 2 [mu] m, more preferably about 0.5 to 1 [mu] m. As the vapor deposition method, CVD or PVD may be used. In addition, it is not limited to a sputtering method or a vapor deposition method, As long as a desired MgO thin film layer can be formed, you may use another method as needed.

  Next, step (ii) of the production method of the present invention is performed. That is, the MgO raw material layer is formed by applying the MgO raw material on the first protective layer (preferably the MgO thin film layer). The MgO raw material used includes MgO powder and solvent A and solvent B or solvent A, solvent B and solvent C. The MgO powder is preferably MgO crystal powder (MgO microcrystal powder), more preferably MgO single crystal powder. The particle diameter of the MgO crystal powder or MgO single crystal powder is preferably about 0.2 to 20 μm, more preferably about 0.5 to 10 μm. The amount of the MgO powder contained in the MgO raw material is preferably 0.3 to 20% by mass (based on MgO raw material), more preferably 0.3 to 10% by mass (based on MgO raw material), and still more preferably 0.8. 3 to 5% by mass (based on MgO raw material), for example, about 1% by mass (based on MgO raw material).

  The solvent contained in the MgO raw material is solvent A and solvent B, or solvent A, solvent B and solvent C. In order to suppress convection during drying, the vapor pressures of solvent A, solvent B and solvent C are separated to some extent. Need to be. The ratio of the sum of solvent B and solvent C to the total solvent is 3.5% by mass or more, the vapor pressure of solvent A at 20 ° C. is 50 Pa or more, and the vapor pressure of solvent B / C at 20 ° C. is 20 Pa or less. It is.

  The ratio of the sum of the solvent B and the solvent C to the total solvent contained in the MgO raw material (that is, the content ratio of the solvent B and the solvent C) is 3.5% by mass or more. Here, “total solvent” as used in this specification means “solvent A and solvent B” substantially when the solvent is composed of solvent A and solvent B, and the solvent is the other solvent. In the case of additionally containing (that is, at least one other solvent), it means substantially “solvent A, solvent B and other solvents”. In addition, the ratio of the solvent B with respect to the total solvent becomes like this. Preferably it is 3.5 to 20 mass%, More preferably, it is 3.5 to 12 mass%. The solvent A is a water-soluble alcohol solvent, and examples thereof include organic solvents such as 3-methoxy-3-methyl-1-butanol, 2-ethoxyethanol, and 2-methoxyethanol. The solvent B and the solvent C are water-soluble glycol solvents having a hydroxy group or derivatives thereof, such as propylene glycol, 1,3-butylene glycol, 1,5-pentanediol, diethylene glycol monoethyl ether 2- (2 -Ethoxyethoxy) ethanol, diethylene glycol monoethyl ether acetate 2- (2-ethoxyethoxy) ethyl acetate, diethylene glycol monomethyl ether, 1,3-butanediol-3-methyl-1-acetate and the like.

  A slit coater method is preferably used for coating the MgO raw material. The “slit coater method” is a method in which a pasty raw material is applied to a predetermined surface by pumping and discharging a pasty raw material from a wide nozzle. When such a slit coater method is used, the MgO raw material preferably has a viscosity of about 7 mPa · s or less from the viewpoint of preventing aggregation of the MgO powder. Here, it should be noted that the viscosity used herein substantially means “viscosity at a shear rate of 100 s −1 and a temperature of 25 ° C.” since MgO raw materials can generally be non-Newtonian fluids. The viscosity of the MgO raw material is preferably 3 mPa · s or more and 7 mPa · s or less, more preferably 4 mPa · s or more and 7 mPa · s or less. This is because a raw material viscosity of 7 mPa · s or less is required from the slit coater, and 3 mPa · s or more is desirable from the viewpoint of suppressing the precipitation of MgO powder, and depends on the particle diameter of MgO powder, but 4 mPa · s. -It is because the direction more than s has the big effect which suppresses sedimentation of MgO powder.

  When the slit coater method is used, the thickness of the MgO raw material layer formed by application of the MgO raw material (hereinafter also referred to as “Wet film thickness”) is preferably about 5 μm to about 13 μm.

  When the formation of the MgO raw material layer is completed, step (iii) of the manufacturing method of the present invention is then performed. That is, the MgO raw material layer is dried to obtain the second protective layer 16b (that is, MgO crystal layer) from the MgO raw material layer. Here, “drying” substantially means that the solvent (more specifically, solvent A, solvent B, solvent C) contained in the MgO raw material layer is vaporized and removed from the MgO raw material layer. doing. For example, the MgO raw material layer may be placed under a reduced pressure of 7 to 0.1 Pa or under vacuum, or may be subjected to a heat treatment at about 100 ° C. to 400 ° C. under atmospheric pressure. If necessary, “under reduced pressure or under vacuum” and “heat treatment” may be combined. The thickness of the second protective layer 16b obtained after drying can be reduced from the thickness of the MgO raw material layer to about 0.1 to 5 μm due to the removal of the solvent.

  Through the above steps (i) to (iii), a protective layer having a two-layer structure composed of the first protective layer 16a (preferably MgO thin film layer) and the second protective layer 16b (MgO crystal layer) is formed. 1 will be completed.

In contrast to the production of the front plate 1, the back plate 2 is produced as follows. First, a method of screen-printing a paste containing silver (Ag) material on a glass substrate 20 or a photolithography method of exposing and developing after forming a metal film mainly composed of silver on the entire surface is used. Then, a precursor layer is formed by a method such as patterning, and the address electrode 21 is formed by baking the precursor layer at a desired temperature (for example, about 400 ° C. to about 700 ° C.). Next, a dielectric layer 22 serving as a base dielectric layer is formed on the substrate 20 on which the address electrodes 21 are formed. First, a “dielectric material paste mainly composed of a glass component (a material formed from SiO ₂ , B ₂ O _3, etc.) and a vehicle component” is applied by a die coating method or the like to form a dielectric paste layer. Thereafter, the dielectric layer 22 can be formed by firing the dielectric paste layer. Next, the partition walls 23 are formed at a predetermined pitch. Specifically, a partition wall forming raw material paste is applied on the dielectric layer 22 and patterned into a predetermined shape to form a partition wall material layer, which is then baked to form the partition wall 23. . For example, by a photolithography method in which a raw material paste mainly composed of a low-melting glass material, a vehicle component and a filler is applied by a die coating method or a printing method, dried at about 100 ° C. to 200 ° C., and then exposed and developed. The partition wall 23 is formed by patterning and then baking at about 400 ° C. to about 700 ° C. The partition wall 23 is formed by forming a partition wall material film by screen printing and then drying, and after pattern formation by exposure / development processing using a dry film containing a photosensitive resin, excavation is performed by sandblasting, and the dry film is peeled off. It can also be formed by firing. Next, the phosphor layer 25 is formed. A phosphor raw material paste containing a phosphor material is applied on the dielectric layer 22 between the adjacent barrier ribs 23 and on the side surfaces of the barrier ribs 23 and fired to form the phosphor layer 25. More specifically, the phosphor layer 25 is formed by applying a raw material paste mainly composed of phosphor powder and a vehicle component by a nozzle discharge method or the like, and then subjecting to drying at about 100 ° C.

  Through the above steps, the address electrode 21, dielectric layer 22, partition wall 23, and phosphor layer 25, which are predetermined constituent members, are formed on the substrate 20, and the back plate 2 is completed.

  In this way, the front plate 1 and the back plate 2 provided with predetermined constituent members are arranged to face each other so that the display electrodes 11 and the address electrodes 21 are orthogonal to each other. Next, the periphery of the front plate 1 and the back plate 2 is sealed with glass frit. Then, after evacuating the discharge space 30 to be formed, the PDP 100 is finally completed by enclosing a discharge gas (such as helium, neon and / or xenon) preferably at a pressure of 55 kPa to 80 kPa.

  Although the embodiments of the present invention have been described above, those skilled in the art will readily understand that the present invention is not limited thereto and various modifications can be made. For example, the “two-layer structure” of the protective layer composed of the first protective layer and the second protective layer is not limited to the mode in which the first protective layer and the second protective layer can be clearly distinguished, but also the first protective layer. And a mode in which the second protective layer cannot be clearly distinguished (for example, a mode in which the interface between the first protective layer and the second protective layer is unclear) may be used.

[Example]
A test was conducted to investigate the effect of the solvent properties of the ink on the repellent phenomenon without nuclei. In the tests described below, the MgO raw material is called “ink” for convenience.

  An MgO ink containing the following materials was used.

Example 1
MgO crystal powder: 0.5-10 μm MgO single crystal powder Solvent A: 3-methoxy-3-methyl-1-butanol (93 wt%)
・ Solvent B: Propylene glycol (7wt%)
(Example 2)
MgO crystal powder: 0.5-10 μm MgO single crystal powder Solvent A: 3-methoxy-3-methyl-1-butanol (93 wt%)
Solvent B: propylene glycol (3.5 wt%)
Solvent C: Diethylene glycol monoethyl ether acetate 2- (2-ethoxyethoxy) ethyl acetate (3.5 wt%)
(Comparative example)
MgO crystal powder: 0.5-10 μm MgO single crystal powder Solvent A: 3-methoxy-3-methyl-1-butanol (93 wt%)
Solvent B: α-terpineol (7 wt%)
Table 1 shows typical physical properties of the solvents used in this test. The table shows the representative physical properties of the solvents in the examples and comparative examples. Here, the MgO powder concentration was 0.7% by mass.

  In preparing the MgO ink, 2000 g of the mixture composed of the above materials was sonicated for 30 minutes with an amplitude of 20 μm so as not to cause lattice defects such as chipping on the surface of the MgO crystal powder, and the MgO crystal powder was dispersed in the solvent. It was.

  The obtained MgO ink was applied on a MgO thin film layer (thickness of about 0.7 μm) formed by a vapor deposition method. Specifically, MgO ink was applied by a slit coater method so that the wet film thickness was 12 μm (use of slit coater equipment manufactured by the applicant). Next, the atmosphere was reduced in pressure to 1 Pa and subjected to vacuum drying, whereby the solvent was vaporized and an MgO crystal layer (thickness of about 1.0 μm) was formed.

  The substrate used was a substrate stored for about two months in a clean room in order to promote water absorption to the substrate after deposition of the MgO thin film layer.

  FIG. 3 is a perspective view schematically showing an embodiment of the “nuclear-free repelling phenomenon”. When the MgO crystal layer is formed by the slit coater method, the “region 53 where the MgO crystal powder does not exist in the MgO thin film layer” or “the region 53 having a lower coverage than the surrounding region 52” as shown in FIG. A “nuclear repellency phenomenon” such as formation may occur.

  Therefore, the “nuclear-free repelling phenomenon” generated in each example and comparative example was observed visually and with an optical microscope, and the number of occurrences was counted. As a result, the “nuclear-free repelling phenomenon” occurred in Example 1 and Example 2. The number of "" significantly decreased from the number of "nuclear-free repelling phenomenon" that occurred in the comparative example.

  Here, the mechanism by which the “nuclear repellency phenomenon” occurs will be described. When MgO ink is applied using a slit coater, a certain amount of moisture is adsorbed on the surface of the MgO thin film layer. When the MgO ink applied to the MgO thin film layer is vacuum-dried, the solvent A having a high vapor pressure evaporates preferentially, so there is a period in which the ratio of the solvent B and the solvent C in the MgO ink is high. At this time, when the solvent B or the solvent C is water-insoluble, it is considered that the moisture adsorbed on the surface of the MgO thin film layer and the MgO ink are repelled and a “nuclear repelling phenomenon” occurs. The reason why the number of “nuclear-free repelling phenomenon” generated in the comparative example was larger than those in Example 1 and Example 2 was because α-terpineol, which is a water-insoluble solvent, was included in the MgO ink used in the comparative example. It is expected to be.

  From the above results, it was found that all the solvents constituting the MgO ink must be water-soluble in order to suppress the “nuclear repellency phenomenon”.

  Since the PDP finally obtained through the manufacturing method of the present invention has good discharge characteristics, it can be suitably used as a plasma television for commercial use and a commercial plasma television, and also suitable as various other display devices. Can be used.

  Moreover, the manufacturing method of this invention is not limited to PDP, It can utilize also in another product field. For example, in the field of batteries, electronic components, etc., it can be applied to applications in which a polymer / dispersant-free ink is applied to a substrate by a slit coater method to form a powder layer with a very uniform coverage. .

DESCRIPTION OF SYMBOLS 1 Front plate 2 Back plate 10 Front board side board 11 Front board side electrode (display electrode)
12 Scan electrode 12a Transparent electrode 12b Bus electrode 13 Sustain electrode 13a Transparent electrode 13b Bus electrode 14 Black stripe (light shielding layer)
15 Dielectric layer on the front plate side 16 Protective layer 16a First protective layer (MgO thin film layer)
16b Second protective layer (MgO crystal layer or MgO powder layer)
51 Projection of MgO thin film layer 52 Region where MgO powder is present at a predetermined coverage 53 Region where MgO powder is not present or coverage is lower than the peripheral region 52

Claims (3)

A method of manufacturing a plasma display panel in which an electrode, a dielectric layer, and a protective layer are formed on a substrate,
Forming the protective layer,
(I) forming a first protective layer on the dielectric layer formed on the substrate by sputtering or vapor deposition;
(Ii) forming a MgO raw material layer by applying an MgO raw material on the first protective layer by a slit coater method, and (iii) drying the MgO raw material layer to form a second protective layer. ,
The method for producing a plasma display panel, wherein the MgO raw material contains MgO powder and two or more kinds of solvents, and each of the two or more kinds of solvents is a water-soluble organic solvent having one or more hydroxy groups. The two or more kinds of solvents include three kinds of a solvent A, a solvent B, and a solvent C, and a ratio of the sum of the solvent B and the solvent C to the total amount of the solvent is 3.5% by mass or more. 2. A method for producing a plasma display panel according to 1. The method for manufacturing a plasma display panel according to claim 1 or 2, wherein the solvent A is an alcohol-based organic solvent, and the solvent B and the solvent C are glycol ether-based organic solvents or glycol ether-based derivatives.

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