JP2008057038A - VAPOR DEPOSITION MATERIAL FOR SURFACE TREATMENT, MgO PROTECTIVE FILM USING THE VAPOR DEPOSITION MATERIAL, AND METHOD FOR PRODUCING THE MgO PROTECTIVE FILM - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the discharge response properties and luminous efficiency of an FPD (Flat Panel Display) using an MgO protective film without deteriorating the durability of the MgO protective film. <P>SOLUTION: In the vapor deposition material 11 for surface treatment in which each cavity 13a is formed on the surface of an MgO protective film 13 for an FPD, and further, each particle 13b is stuck thereto, MgO is comprised as the main component, and the average particle diameter is 0.5 μm to 1 mm. By splashing the vapor deposition material 11 for surface treatment to the surface of the MgO protective film 13, each cavity 13a with the average hole diameter of 50 to 10,000 nm is formed, and also, each particle 13b with the average particle diameter of 50 to 10,000 nm is stuck thereto. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an evaporation material for treating the surface of an MgO protective film for FPD (Flat Panel Display) such as PDP (Plasma Display Panel), PALC (Plasma Addressed Liquid Crystal Display), and the like. The present invention relates to a MgO protective film whose surface has been treated using, and a method for producing a MgO protective film whose surface has been treated.

Conventionally, each of a front substrate and a rear substrate facing each other through a discharge space, a plurality of row electrode pairs between the front substrate and the rear substrate, and a row electrode pair extending in a direction intersecting the row electrode pair There has been disclosed a plasma display panel provided with a plurality of column electrodes each forming a unit light emitting region in a discharge space at an intersection (see, for example, Patent Document 1). In this plasma display panel, a magnesium oxide crystal that emits cathode luminescence having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam is formed on a portion facing a unit light emitting region between a front substrate and a back substrate. A magnesium oxide layer is provided. Further, the magnesium oxide crystal is generated by a gas phase oxidation method, and the particle size thereof is 2000 mm (200 nm) or more. Further, the magnesium oxide layer is formed by applying a paste containing a magnesium oxide crystal to the surface of the dielectric layer by a screen printing method, an offset printing method, a dispenser method, an ink jet method, a roll coating method, or the like. The powder is formed by adhering magnesium crystal powder to the surface of the dielectric layer by spraying or electrostatic coating.
In the plasma display panel thus configured, the magnesium oxide crystal contained in the magnesium oxide layer is excited by an electron beam at a position facing the discharge cell, and has a peak in the wavelength range of 200 to 300 nm. Since the luminescence emission is performed, the discharge generated in the discharge cell can be speeded up. For example, the priming effect by the reset discharge can be maintained for a long time, and the address discharge can be speeded up. As a result, discharge characteristics such as the discharge probability and discharge delay in the plasma display panel are improved, and good discharge characteristics can be obtained.
International Publication No. 2005/031782 (Claims 1, 2 and 4, Paragraph [0009], Paragraph [0084] to Paragraph [0086], FIGS. 19 and 20)

However, in the conventional plasma display panel disclosed in Patent Document 1, when a magnesium oxide layer containing magnesium oxide crystals is formed on the surface of the dielectric layer, a solvent is used or the magnesium oxide layer is opened to the atmosphere. Therefore, there is a problem that impurities are mixed.
In addition, the conventional plasma display panel disclosed in Patent Document 1 has a problem that the performance deteriorates due to long-term use because the adhesion strength of the magnesium oxide layer containing the magnesium oxide crystal to the dielectric layer is low. It was.
An object of the present invention is to provide a deposition material for surface treatment that can improve the discharge response characteristics and the light emission efficiency without impairing the durability as an MgO protective film.
Another object of the present invention is to provide a MgO protective film and a method for producing this MgO protective film that can improve discharge response characteristics and luminous efficiency without impairing durability.

As shown in FIGS. 1 to 3, the invention according to claim 1 is a surface treatment vapor deposition material 11 for forming a depression 13 a on the surface of an MgO protective film 13 for FPD 30 and attaching particles 13 b, and includes MgO Is a vapor deposition material for surface treatment, characterized by having an average particle size of 0.5 μm to 1 mm.
In the vapor deposition for surface treatment described in claim 1, since the average particle diameter of the vapor deposition material 11 is relatively small, 0.5 μm to 1 mm, the vapor deposition material 11 is cracked or peeled during the vapor deposition to become fine particles. These particles float due to a vapor flow or the like and come into contact with the surface of the MgO protective film 13, and a recess 13 a is formed on the surface of the MgO protective film 13, or the particles 13 b adhere as they are. Thus, the presence of the depression 13a and the particle 13b on the surface of the MgO protective film 13 increases the surface area of the MgO protective film 13, and the electrons easily stay on the periphery of the depression 13a and the surface of the particle 13b. Due to the presence of the depression 13a and the particle 13b, the sharp portion is increased, and the density of electrons to the sharp portion is increased, and electrons are easily emitted from the periphery of the depression 13a and the surface of the particle 13b.

In the invention according to claim 2, as shown in FIGS. 1 and 2, the surface treatment vapor deposition material 11 according to claim 1 is splashed on the surface to form a recess 13a having an average hole diameter of 50 nm to 10000 nm. And an MgO protective film to which particles 13b having an average particle diameter of 50 nm to 10000 nm are attached.
In the MgO protective film according to the second aspect, since the depressions 13a and particles 13b having a predetermined size are present on the surface of the MgO protective film 13, the surface area of the MgO protective film 13 is increased, and the depressions 13a Electrons are likely to stay on the periphery and the surface of the particle 13b, and the presence of the depression 13a and the particle 13b increases the sharp portion, and the density of electrons to the sharp portion increases, and the periphery of the depression 13a and the surface of the particle 13b. It becomes easy to emit electrons from.

As shown in FIGS. 1 to 3, the invention according to claim 3 is a laminate mainly composed of MgO having an average particle diameter of 5 to 30 mm on the surface of the substrate 12 for FPD 30 in a chamber 23 maintained at a predetermined degree of vacuum. The surface treatment according to claim 1, wherein the surface of the MgO protective film 23 is formed on the surface of the MgO protective film 13 while the inside of the chamber 23 is continuously maintained at a predetermined degree of vacuum. A step of forming a recess 13a having an average hole diameter of 50 nm to 10000 nm and adhering particles 13b having an average particle diameter of 50 nm to 10000 nm to the surface of the MgO protective film 13 by causing the evaporation material 11 to be splashed by a vacuum evaporation method. This is a method for manufacturing a protective film.
In the manufacturing method of the MgO protective film described in claim 3, after forming the MgO protective film 13 using the MgO vapor deposition material 14 having an average particle diameter of 5 to 30 mm in the chamber 23 maintained at a predetermined degree of vacuum, In a state where the inside of the chamber 23 is continuously maintained at a predetermined degree of vacuum, the surface treatment vapor deposition material 11 having an average particle size of 0.5 μm to 1 mm is splashed on the surface of the MgO protective film 13 to form a predetermined recess 13a and a predetermined value. Since the particles 13b are attached, a solvent is not used or opened to the atmosphere as in the conventional case, and impurities are not mixed into the MgO protective film 13.

According to the present invention, since the deposition material for surface treatment has MgO as a main component and the average particle size is 0.5 μm to 1 mm, the deposition material is cracked or peeled during deposition to form fine particles. It floats by a flow or the like and comes into contact with the surface of the MgO protective film, so that depressions are formed on the surface of the MgO protective film or particles adhere as they are. Thus, the presence of depressions and particles on the surface of the MgO protective film increases the surface area of the MgO protective film, making it easier for electrons to stay on the periphery of the depressions and the surface of the particles, and the presence of depressions and particles. The sharp portion increases, the electron density to the sharp portion increases, and it becomes easier to emit electrons from the periphery of the depression and the surface of the particle. As a result, it is possible to improve the discharge response characteristic and the light emission efficiency of the FPD using this MgO protective film.
In addition, the surface treatment vapor deposition material is splashed on the surface, so that depressions with an average hole diameter of 50 nm to 10000 nm can be formed in the MgO protective film, and particles with an average particle diameter of 50 nm to 10000 nm can be attached to the surface of the MgO protective film. For example, the presence of depressions and particles on the surface of the MgO protective film increases the surface area of the MgO protective film, making it easier for electrons to stay on the periphery of the depressions and the surface of the particles, and the presence of depressions and particles to sharpen the edges. And the density of electrons at the pointed portion increases, and electrons are easily emitted from the periphery of the depression and the surface of the particles. As a result, similarly to the above, the discharge response characteristic and the light emission efficiency of the FPD using this MgO protective film can be improved.
Further, an MgO protective film is formed on the substrate surface in a chamber maintained at a predetermined degree of vacuum by a vacuum evaporation method using a deposition material mainly composed of MgO having an average particle diameter of 5 to 30 mm, and the chamber is continuously subjected to a predetermined level. A predetermined depression is formed on the surface of the MgO protective film by spraying a surface treatment vapor deposition material having an average particle size of 0.5 μm to 1 mm on the surface of the MgO protective film with a vacuum degree while maintaining the degree of vacuum. If predetermined particles are attached, no solvent is used or the air is not opened to the atmosphere as in the conventional case, so that impurities are not mixed in the MgO protective film. As a result, the durability of the MgO protective film is not impaired.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
As shown in FIG. 1, the deposition material 11 for surface treatment forms a recess 13a on the surface of the MgO protective film 13 of the windshield substrate 12 for a plasma display panel (hereinafter referred to as PDP) and attaches particles 13b. It is used for surface treatment of the MgO protective film 13. This vapor deposition material 11 has MgO as a main component. Specifically, the MgO purity of the vapor deposition material 11 is 98% or more, preferably 99.0 to 99.9%, and contains extremely small amounts of Y, La, Ce, and the like. The average particle size of the vapor deposition material 11 is 0.5 μm to 1 mm, preferably 5 μm to 0.1 mm, and the relative density of the vapor deposition material 11 is 70 to 90%, preferably 80 to 90%. Here, the reason why the purity of the vapor deposition material 11 is limited to 98% or more is that if it is less than 98%, the discharge response time becomes long and the reproducibility of the data of the discharge response time is inferior. The reason why a very small amount of Y, La, Ce, and the like is contained is that the PDP having the MgO protective film 13 that has been subjected to the above surface treatment obtains good discharge responsiveness over a wide temperature range. Further, the average particle size of the vapor deposition material 11 is limited to the range of 0.5 μm to 1 mm because if it is less than 0.5 μm, it is too fine and difficult to handle, and if it exceeds 1 mm, splash may occur during the surface treatment of the MgO protective film 13. It is because it becomes difficult to generate. Furthermore, the reason why the relative density of the vapor deposition material 11 is limited to a range of 70 to 90% is to efficiently generate a predetermined amount of splash during the surface treatment of the MgO protective film 13.

  On the other hand, it is preferable that the components of the stacking vapor deposition material 14 (FIG. 2A) for forming the MgO protective film 13 on the surface of the front glass substrate 12 are configured in the same manner as the surface treatment vapor deposition material 11. However, the average particle diameter of the vapor deposition material 14 for lamination is 5 mm to 30 mm, preferably 5 mm to 15 mm, and the relative density of the vapor deposition material 14 for lamination is 90% or more, preferably 95% or more. Here, the average particle diameter of the vapor deposition material 14 for laminating was limited to the range of 5 mm to 30 mm. If the thickness was less than 5 mm, the MgO protective film 13 was too small during the film formation, and splash was likely to occur. This is because a flat MgO protective film 13 cannot be obtained, and if it exceeds 30 mm, it becomes difficult to handle in the actual manufacturing process. Further, the relative density of the vapor deposition material 14 is limited to 90% or more. When the deposition density is less than 90%, the splash increases when the MgO protective film 13 is formed, and the MgO protective film 13 having a dense and relatively flat surface is formed. It is because it cannot be obtained. As shown in FIGS. 1 and 2, electrodes 16 such as a sustain electrode and a scan electrode are formed on the surface of the front glass substrate 12, and a dielectric glass layer 17 is formed so as to cover these electrodes 16. It is formed. Thereby, the MgO protective film 13 is formed on the surface of the dielectric glass layer 17.

A method for forming the MgO protective film 13 and a surface treatment method will be described.
First, as shown in FIG. 2A, the MgO protective film 13 is formed on the surface of the front glass substrate 12 by the vacuum deposition method on the surface of the front glass substrate 12 in the chamber 23 maintained at a predetermined degree of vacuum. Here, examples of the vacuum evaporation method include an electron beam evaporation method and an ion plating method. The electron beam evaporation method is a method in which the stacking vapor deposition material 14 is irradiated with an electron beam and heated to evaporate and eject MgO particles and deposit the MgO particles on the surface of the dielectric glass layer 17. In the ion plating method, the front glass substrate 12 is used as a cathode, glow discharge is caused, and MgO particles evaporated and ejected from the deposition material 14 are accelerated by being ionized or excited and then collided with the dielectric glass layer 17. This is a method of depositing. As a specific method for forming the MgO protective film 13, first, the front glass substrate 12 on which the electrode 16 and the dielectric glass layer 17 are formed is held by the holding means 24 of the vacuum vapor deposition apparatus 20, and the first hearth 21. The vapor deposition material 14 for laminating is put in. Next, the chamber 23 is maintained at a predetermined degree of vacuum, that is, 5 × 10 ⁻⁵ to 1 × 10 ⁻³ Pa, preferably 5 × 10 ^{−5 to} 5 × 10 ⁻⁴ Pa. The stacking vapor deposition material 14 is evaporated by an electron beam or glow discharge and deposited on the surface of the dielectric glass layer 17. As a result, a dense MgO protective film 13 having a relatively flat surface is formed on the surface of the dielectric glass layer 17 (FIG. 2A). Here, the ^reason why the degree of vacuum in the chamber 23 is limited to the range of 5 × 10 ⁻⁵ to 1 × 10 ⁻³ Pa is that if it is less than 5 × 10 ⁻⁵ Pa, the inside of the chamber 23 is made more airtight than necessary. This is because the power of the pump is required, and when it exceeds 1 × 10 ⁻³ Pa, the quality of the MgO protective film 13 formed on the surface of the dielectric glass layer 17 is deteriorated. The oxygen partial pressure in the chamber 23 is set to 5 × 10 ^{−3 to} 5 × 10 ⁻¹ Pa, preferably 0.7 × 10 ⁻³ to 2 × 10 ⁻² Pa. Here, the oxygen partial pressure in the chamber 23 is limited to the range of 5 × 10 ^{−3 to} 5 × 10 ⁻¹ Pa. When the oxygen partial pressure is less than 5 × 10 ⁻³ Pa, the discharge responsiveness is delayed due to excessive oxygen deficiency. This is because, if it exceeds 5 × 10 ⁻¹ Pa, the required discharge voltage increases due to excess oxygen.

Next, as shown in FIG. 2B, the surface treatment vapor deposition material 11 is splashed on the surface of the MgO protective film 13 by a vacuum vapor deposition method while the chamber 23 is kept at a predetermined degree of vacuum. Thus, the predetermined depression 13a is formed and the predetermined particles 13b are attached. Specifically, the chamber 23 is kept at a predetermined degree of vacuum, that is, 5 × 10 ⁻⁵ to 1 × 10 ⁻³ Pa, preferably 5 × 10 ^{−5 to} 5 × 10 ⁻⁴ Pa. The surface treatment vapor deposition material 11 in the second hearth 22 is splashed on the surface of the protective film 13 by electron beam or glow discharge, and the average hole diameter of 50 nm to 10000 nm, preferably 100 nm to 500 nm is formed on the surface of the MgO protective film 13. The depression 13a is formed, and particles 13b having an average particle diameter of 50 nm to 10000 nm, preferably 100 nm to 500 nm are attached (FIG. 2B). Here, the reason why the average hole diameter of the recess 13a is limited to the range of 50 nm to 10000 nm is that when it is less than 50 nm, it becomes smaller than the recess generated when the MgO protective film 13a is formed by using the deposition material 11 for stacking, and the discharge response. This is because the effect of improving the characteristics and light emission efficiency is not manifested, and when the thickness exceeds 10,000 nm, the variation in the discharge rate increases. Moreover, the reason why the average particle size of the adhering particles 13b is limited to the range of 50 nm to 10000 nm is that sufficient discharge cannot be performed if the particle diameter is less than 50 nm, and speeding up of electron emission is hindered if the particle diameter exceeds 10,000 nm. . When the surface treatment vapor deposition material 11 is irradiated with an electron beam or a glow discharge is generated in the surface treatment vapor deposition material 11, the surface treatment vapor deposition material 11 having a relatively small average particle size is cracked or peeled off and becomes fine. These particles float by the vapor flow in the chamber 23 and come into contact with the surface of the MgO protective film 13. When the contacted particles are peeled off from the MgO protective film 13, a recess 13 a is formed on the surface of the MgO protective film 13. When the contacted particles are not peeled off from the MgO protective film 13, the particles are left as they are on the surface of the MgO protective film 13. To attach particles 123b.

  Thus, the presence of the depression 13a and the particles 13b on the surface of the MgO protective film 13 increases the surface area of the MgO protective film 13, and the electrons easily stay on the periphery of the depression 13a and the surface of the attached particles 13b. The sharp portion increases due to the presence of the depression 13a and the adhering particles 13b, and the density of electrons to the sharp portion increases, and electrons are easily emitted from the periphery of the depression 13a and the surface of the adhering particles 13b. As a result, it is possible to improve the discharge response characteristics and light emission efficiency of the PDP using the MgO protective film 13. Further, the front glass substrate 12 is not opened to the atmosphere between the step of forming the MgO protective film 13 on the surface of the dielectric glass layer 17 and the step of forming the depression 13a on the surface of the MgO protective film 13 and attaching the particles 13b. In addition, the step of forming the MgO protective film 13 on the surface of the dielectric glass layer 17 and the step of forming the depression 13a on the surface of the MgO protective film 13 and attaching the particles 13b have the same components as the same vacuum vapor deposition apparatus 20. Since the vapor deposition material is used, impurities are not mixed into the MgO protective film 13, and the adhesive force between the MgO protective film 13 and the attached particles 13b can be strengthened. As a result, the MgO protective film 13 hardly deteriorates even when the PDP using the MgO protective film 13 is used for a long period of time.

FIG. 3 shows the internal structure of the PDP 30 using the MgO protective film 13 thus formed and surface-treated.
In the surface discharge AC type PDP 30, the sustain electrode 31 and the scan electrode 32 are usually arranged in parallel in a horizontal direction of the screen of the windshield substrate 12. An address electrode 34 is arranged in the vertical direction of the screen of the rear glass substrate 33. The gap between the sustain electrode 31 and the scan electrode 32 is called a discharge gap, and this gap is selected to be about 80 μm. The front glass substrate 12 and the rear glass substrate 33 are separated by a partition wall 36 having a height of about 100 to 150 μm, and phosphor powder is applied to the wall surface and the bottom of the partition wall 36. In the case of color display, three colors (R, G, B) of phosphors 38G, 38B, and 38R are respectively applied to the back and bottom of the barrier rib 36 that forms three discharge spaces 37 arranged in the line direction. Sub-pixels (unit light-emitting regions) are formed, and these are defined as one pixel. Gas is sealed in the discharge space 37 formed by the front glass substrate 12, the rear glass substrate 33, and the barrier ribs 36. As this sealed gas, a mixed gas of an inert gas such as Ne (neon) or Xe (xenon) is used.
A protective film 13 having high sputtering resistance is provided on the surface of the dielectric glass layer 17 covering the sustain electrode 31 and the scan electrode 32 in order to reduce ion bombardment caused by the discharge gas during discharge. In the PDP 30, since the material, film quality and shape of the protective film 13 have a great influence on the discharge characteristics, the protective film 13 acts as a discharge electrode. As this protective film 13, the MgO protective film of the present invention, which is an insulator having excellent sputtering resistance and a high secondary electron emission coefficient, is used.

  In the matrix type AC type PDP 30 configured as described above, the sustain electrode 31, the scan electrode 32, and the address electrode 34 facing each other in the discharge space 37 provided between the front glass substrate 12 and the rear glass substrate 33 are arranged. Plasma display is generated in the meantime, and display is performed by applying ultraviolet rays generated from the gas sealed in the discharge space 37 to the phosphors 38G, 38B, and 38R provided in the discharge space 37. A memory effect is used for maintaining (sustaining) the lighting state of a cell as a display element. When displaying, first, the wall charge of the entire screen is erased (reset) from the end of sustain of one image to the addressing (writing) of the next image. Next, line-sequential addressing (writing) for accumulating wall charges only in the cells to be lit (emitted) is performed. Thereafter, a voltage (sustain voltage) lower than the discharge start voltage having an alternating polarity is applied to all the cells simultaneously. In a cell in which wall charges exist, the wall voltage is superimposed on the sustain voltage, so that the effective voltage applied to the cell exceeds the discharge start voltage and discharge occurs. By increasing the application frequency of the sustain voltage, an apparently continuous lighting state can be obtained.

  In the addressing (writing), wall charges are accumulated by performing address discharge between the address electrode of the rear glass substrate and the scan electrode of the front glass substrate. For example, in a conventional PDP with a resolution of VGA (Visual Graphics Array) and 256 gradations (8 subfields), if address discharge is performed at 3 μs, it is necessary to sequentially write 480 lines. Therefore, about 10% of the driving time is consumed for erasing the wall charges and about 70% is written for writing the image data, and the time for actually displaying the image is only about the remaining 20%. In the case of PDP, the brightness of the panel is recognized brighter as the image display time is longer. In order to improve panel brightness, the number of address ICs that drive the address electrodes is doubled, and the upper and lower parts of the image are written separately (dual scan), thereby shortening the writing time and extending the image display time. . However, when this method is used, there is a problem that the circuit cost increases.

  On the other hand, the MgO protective film 13 of the present invention can hold electrons at a high density on the periphery of the recess 13a and the surface of the adhering particles 13b. Can be achieved. As a result, the PDP 30 using the MgO protective film 13 of the present invention can display a high-definition and stable image, can suppress the applied voltage, and can contribute to energy saving. In addition, since the PDP 30 using the MgO protective film 13 of the present invention can extend the image display time, the panel brightness can be improved. On the other hand, the number of address ICs can be greatly reduced without lowering the panel brightness.

Next, examples of the present invention will be described in detail together with comparative examples.
<Example 1>
As shown in FIG. 2A, the stacking vapor deposition material 14 has a MgO purity of 99.95%, a relative density of 98%, and a diameter and thickness of 5 mm and 1.6 mm, respectively. Shaped pellets were prepared, and the vapor deposition material 14 was placed in the first hearth 21. A rectangular plate-shaped glass substrate 12 having a length, width and thickness of 150 mm, 150 mm and 2.8 mm, respectively, was prepared. On the surface of the glass substrate 12, an ITO (Indium Tin Oxide) electrode 16 for a discharge gap having a thickness of 80 μm and a dielectric glass layer 17 covering the ITO electrode 16 were formed in advance. The glass substrate 12 was adsorbed to the holding plate 24a of the holding means 24. On the dielectric glass layer 17 formed on the glass substrate 12, the stacking vapor deposition material 14 in the first hearth 21 was heated and evaporated by an electron beam heating means to form an MgO protective film 13 having a thickness of 800 nm. (FIG. 2 (a)). The film formation conditions at this time were an ultimate vacuum of 1.0 × 10 ⁻⁴ Pa, an oxygen partial pressure of 1.0 × 10 ⁻² Pa, and a substrate temperature of 200 ° C. Next, the surface treatment vapor deposition material 11 having an average particle diameter of 100 μm in the second hearth 22 is heated and evaporated by the electron beam heating means under the same film formation conditions as the above film formation conditions, and a depression is formed on the surface of the MgO protective film 13. 13a was formed and particles 13b were attached (FIGS. 1 and 2B). The glass substrate 12 in which the depression 13a was formed on the surface of the MgO protective film 13 and the particles 13b were adhered was taken as Example 1.

<Example 2>
A depression was formed on the surface of the MgO protective film of the glass substrate and the particles were adhered in the same manner as in Example 1 except that the vapor deposition material for surface treatment having an average particle diameter of 0.5 μm was used. This glass substrate was referred to as Example 2.
<Example 3>
Except that a vapor deposition material for surface treatment having an average particle diameter of 2 μm was used, in the same manner as in Example 1, depressions were formed on the surface of the MgO protective film of the glass substrate and particles were adhered. This glass substrate was referred to as Example 3.
<Example 4>
A depression was formed on the surface of the MgO protective film of the glass substrate and the particles were adhered in the same manner as in Example 1 except that the vapor deposition material for surface treatment having an average particle diameter of 10 μm was used. This glass substrate was referred to as Example 4.
<Example 5>
Except that a vapor deposition material for surface treatment having an average particle diameter of 500 μm was used, a depression was formed on the surface of the MgO protective film of the glass substrate and particles were adhered in the same manner as in Example 1. This glass substrate was referred to as Example 5.
<Example 6>
A recess was formed on the surface of the MgO protective film of the glass substrate and the particles were adhered in the same manner as in Example 1 except that the vapor deposition material for surface treatment having an average particle diameter of 1000 μm was used. This glass substrate was referred to as Example 6.
In addition, the measurement of the average particle diameter of the vapor deposition material for surface treatment of Examples 1-6 is by measuring the particle diameter of the powder of each vapor deposition material with a particle size distribution measuring device (LEED & NORTHRUP company make: MICROTRAC FRA). went. As the measurement conditions, the solvent was pure water, the dispersant was sodium hexametaphosphate (Na), and the powder of each vapor deposition material was dispersed for 3 minutes, and then the particle size of the powder of each vapor deposition material was measured.

<Comparative Example 1>
A depression was formed on the surface of the MgO protective film of the glass substrate and the particles were adhered in the same manner as in Example 1 except that the vapor deposition material for surface treatment having an average particle diameter of 5000 μm was used. This glass substrate was designated as Comparative Example 1.
<Comparative example 2>
An ITO electrode, a dielectric glass layer, and a dielectric glass layer were formed on the surface of the glass substrate in the same manner as in Example 1 except that no depression was formed on the surface of the MgO protective film using the deposition material for surface treatment and particles were not attached. A MgO protective film was formed. This glass substrate was designated as Comparative Example 2.

<Comparison test and evaluation>
The glass substrate on which the MgO protective films of Examples 1 to 6 and Comparative Examples 1 and 2 were formed was used as a front glass substrate. A rear glass substrate was prepared, and partition walls (ribs) having a height of 150 μm were formed on the rear glass substrate at a pitch of 360 μm. After arranging the front glass substrate and the rear glass substrate to face each other, a Ne-4% Xe mixed gas was injected as a discharge gas into a discharge space formed by the front glass substrate, the rear glass substrate, and the barrier ribs. As a result, a test substrate was obtained. Using this test substrate, a pseudo address discharge test, that is, a counter discharge test between two glass substrates, was performed under each temperature condition of −20 ° C., 30 ° C., and 90 ° C. The test conditions were a discharge gas pressure of 500 Torr, an applied voltage of 200 V, and a frequency of 1 kHz. The test was conducted under such conditions, and the near infrared ray emitted by the discharge was detected by a photomultiplier tube, and the time from the application of voltage to the end of light emission was evaluated as the discharge response time. The discharge response time includes statistical emission variations. The results are shown in Table 1.

  As is apparent from Table 1, when the temperature condition was −20 ° C., the discharge response time was long as 16.4 μsec and 14.7 μsec in Comparative Examples 1 and 2, whereas 6 was as short as 2.0 to 13.8 μsec. When the temperature condition was 30 ° C., the discharge response time was as long as 3.1 μsec and 2.8 μsec in Comparative Examples 1 and 2, whereas in Examples 1-6, 1.1-2. It shortened to 6 μs. Further, when the temperature condition was 90 ° C., the discharge response time was as long as 1.3 μsec and 1.6 μsec in Comparative Examples 1 and 2, whereas in Examples 1-6, 0.7-1. It shortened to 4 μs.

It is principal part cross-section block diagram which shows the state which forms the dent on the surface of a MgO protective film using the deposition material for surface treatment of this invention embodiment, and is making the particle adhere. It is a figure which shows the process of forming a dent on the surface of this MgO protective film, and attaching a particle | grain after forming an MgO protective film on the surface of a front glass board | substrate through an ITO electrode and a dielectric glass layer. It is a principal part cross-sectional perspective view which shows the internal structure of PDP using the MgO protective film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Surface treatment vapor deposition material 12 Front glass substrate 13 MgO protective film 13a Dimple 13b Particle 14 Lamination vapor deposition material 23 Chamber 30 PDP (FPD)

Claims (3)

A surface treatment vapor deposition material (11) for forming depressions (13a) on the surface of an MgO protective film (13) for FPD (30) and attaching particles (13b),
A vapor deposition material for surface treatment, comprising MgO as a main component and an average particle diameter of 0.5 μm to 1 mm.   The surface treatment vapor deposition material (11) according to claim 1 is splashed on the surface to form depressions (13a) having an average hole diameter of 50 nm to 10000 nm, and particles (13b) having an average particle diameter of 50 nm to 10000 nm are formed. Adhered MgO protective film. In a chamber (23) kept at a predetermined degree of vacuum, vacuum deposition is performed on the surface of the substrate (12) for the FPD (30) using a deposition material (14) mainly composed of MgO having an average particle diameter of 5 to 30 mm. Forming a MgO protective film (13) by a method;
The surface treatment vapor deposition material (11) according to claim 1 is splashed by a vacuum vapor deposition method on the surface of the MgO protective film (13) in a state where the inside of the chamber (23) is continuously maintained at a predetermined degree of vacuum. Forming a recess (13a) having an average hole diameter of 50 nm to 10000 nm and adhering particles (13b) having an average particle diameter of 50 nm to 10000 nm on the surface of the MgO protective film (13).

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