JP4741420B2 - Back plate for AC type plasma display panel - Google Patents

Description

  The present invention relates to a back plate for an AC type plasma display panel.

An AC type plasma display panel (hereinafter also referred to as AC type PDP) generally includes a front plate on which discharge electrodes are formed via a discharge space filled with a discharge gas containing Xe (xenon) gas, a vacuum ultraviolet ray, and the like. And a back plate on which a phosphor layer made of a phosphor that emits blue, green, or red light is formed so that the discharge electrode and the phosphor layer face each other. ing. In the AC type PDP having such a structure, each color phosphor layer is irradiated with Xe resonance lines (wavelength 147 nm) and Xe ₂ molecular beams (wavelength 172 nm) generated by the discharge of the discharge electrode on the front plate. By exciting the phosphors, visible light of blue, green, and red is emitted, and an image is displayed by the combination thereof.

As a blue light emitting phosphor used for the back plate of the AC type PDP, a blue light emitting phosphor represented by a composition formula of BaMgAl ₁₀ O ₁₇ : Eu ²⁺ (usually referred to as BAM: Eu ²⁺ ) is generally used. It is. However, BAM: Eu ²⁺ blue-emitting phosphor is another red-emitting phosphor (for example, (Y, Gd) BO ₃ : Eu ³⁺ ) or green-emitting phosphor used for the back plate of AC type PDP. Compared with (for example, Zn ₂ SiO ₄ : Mn ²⁺ ), the decrease in emission luminance over time due to irradiation with vacuum ultraviolet rays is large, so that the AC type PDP using the BAM: Eu ²⁺ blue light emitting phosphor is not used. There is a problem that the white color balance tends to be lost as time passes.

For the above reasons, as a blue light emitting phosphor, CaMgSi ₂ O ₆ : Eu ²⁺ (usually CMS) is less likely to cause a decrease in emission luminance over time due to irradiation with vacuum ultraviolet rays than BAM: Eu ²⁺ blue light emitting phosphor. : Blue luminescent phosphors represented by the composition formula (referred to as Eu ²⁺ ) have been studied. However, the CMS: Eu ²⁺ blue-emitting phosphor has a problem that the emission luminance at the initial stage of use is lower than that of the BAM: Eu ²⁺ blue-emitting phosphor (particularly, the emission luminance due to Xe ₂ molecular beam excitation is low). is there.

Patent Document 1, CMS: As a method for improving the blue light brightness of the AC-type PDP using the Eu ²⁺ blue-emitting phosphor, CMS: Eu ²⁺ blue-emitting phosphor layer comprising a blue-emitting phosphor (No. The Xe resonance line and the Xe molecular beam are absorbed under a single phosphor layer, and ultraviolet rays having a longer wavelength range (wavelength of 210 to 400 nm) than the Xe resonance line and the Xe molecular beam are generated. A method of disposing a wavelength conversion layer (described as a second phosphor layer) made of a second phosphor is disclosed. In Patent Document 1, gadolinium-praseodymium co-activated fluorescent material such as gadolinium-praseodymium co-activated fluoride phosphor (Y, Gd, Pr) F ₃ is used as a wavelength conversion layer material (second phosphor). Praseodymium-activated alumina borate phosphor (Y, Pr) Al ₃ (BO ₃ ) ₄ , praseodymium-activated fluoride phosphor (Y, Pr) F _3, etc., gadolinium-activated alumina borate A gadolinium activated fluorescent material such as a fluorescent material (Y, Gd) Al ₃ (BO ₃ ) ₄ , gadolinium co-activated fluoride fluorescent material (Y, Gd) F ₃ is described.
JP 2006-93075 A

As disclosed in Patent Document 1, a wavelength conversion layer is disposed under a blue light-emitting phosphor layer made of CMS: Eu ²⁺ blue light-emitting phosphor, and Xe ₂ that has passed through the blue light-emitting phosphor layer If the molecular beam is converted into ultraviolet light in a long wavelength region that can be excited by the CMS: Eu ²⁺ blue light-emitting phosphor in the wavelength conversion layer and irradiated to the blue light-emitting phosphor layer, the blue light emission luminance is improved. However, all of the materials for the wavelength conversion layer (second phosphor) described in Patent Document 1 are expensive materials using a rare earth metal as an activator.
Therefore, the object of the present invention is improved by using a material that can be easily obtained and can be industrially manufactured at low cost for the emission luminance of a blue light emitting phosphor layer made of CMS: Eu ²⁺ blue light emitting phosphor. The purpose of this technology is to provide an AC type PDP having a high blue light emission luminance and a small decrease in the light emission luminance over time.

In the present invention, the purity of magnesium oxide is 99.8% by mass or more containing fluorine in the range of 0.01 to 10% by mass on the substrate (however, the purity of magnesium oxide is in the total amount excluding the contained fluorine). The basic composition formula is CaMgSi ₂ O ₆ : Eu through a wavelength conversion layer made of fluorine-containing magnesium oxide having a BET specific surface area in the range of 0.1 to 30 m ² / g. It is a back plate for an AC type plasma display panel in which a blue light emitting phosphor layer made of a blue light emitting phosphor represented by ²⁺ is formed.

Preferred embodiments of the back plate of the present invention are as follows.
(1) The wavelength conversion layer has a thickness in the range of 1 to 10 μm.
(2) The blue light emitting phosphor layer has a thickness in the range of 1 to 30 μm.
(3) The fluorine content of the fluorine-containing magnesium oxide is in the range of 0.03 to 5% by mass.
(4) The magnesium oxide purity of the fluorine-containing magnesium oxide is 99.9% by mass or more.
(5) The BET specific surface area of the fluorine-containing magnesium oxide is in the range of 0.1 to 12 m ² / g.
(6) An address electrode is formed on the substrate, and a blue light emitting phosphor layer is formed on the address electrode via a wavelength conversion layer.
(7) An address electrode and a dielectric layer covering the address electrode are formed on the substrate, and a blue light emitting phosphor layer is formed on the dielectric layer via a wavelength conversion layer.
(8) A partition wall is formed on the substrate, and a blue light emitting phosphor layer is also formed on the wall surface of the partition wall via a wavelength conversion layer.

  The present invention also includes a front plate on which a discharge electrode is formed through a discharge space filled with a discharge gas containing Xe gas, and the back plate of the present invention, wherein the discharge electrode, the blue light emitting phosphor layer, There are also AC type plasma display panels that are arranged so as to face each other.

In the AC type PDP using the back plate of the present invention, blue light emission is stably generated over a long period of time with high luminance, so that the white color balance formed together with other light emission is not easily lost.
Further, in the present invention, by using a material that is easily available instead of a special material and can be manufactured industrially at a low cost, the blue light emission luminance can be increased, and the light emission luminance can be reduced over time. Therefore, the AC type PDP having such excellent performance can be advantageously provided economically.

FIG. 1 of the accompanying drawings is a perspective view of an example of an AC type PDP according to the present invention. FIG. 2 is a cross-sectional view taken along line AA of the AC type PDP shown in FIG.
In FIG. 1, the AC type PDP is composed of a front plate 20 and a back plate 30 which are arranged to face each other through a discharge space 10 filled with a discharge gas containing Xe gas.

As the discharge gas filled in the discharge space 10, a mixed gas of Xe gas and Ne gas is usually used. The concentration of Xe gas in the discharge gas is generally in the range of 5 to 20% by volume. As the Xe gas concentration in the discharge gas, which is a recent trend, increases, the amount of molecular beam of Xe ₂ generated by the discharge of the discharge electrode of the front plate 20 tends to increase. However, in the Xe gas concentration range described above, the vacuum ultraviolet rays generated by the discharge of the discharge electrode of the front plate 20 usually have more Xe resonance lines than Xe ₂ molecular beams.

  The front plate 20 includes a transparent glass substrate 21, a discharge electrode 25 comprising two column electrodes 24a and 24b formed on the surface of the transparent glass substrate 21 on the back plate side, a dielectric layer 26 covering the discharge electrode 25, and a dielectric It consists of a dielectric protective layer 27 formed on the surface of the layer 26 on the back plate side.

  The two column electrodes 24 a and 24 b constituting the discharge electrode 25 are each composed of a wide transparent electrode 22 and a narrow bus electrode 23. The transparent electrode 22 is generally made of a conductive metal oxide film such as an ITO (indium tin oxide) film or a tin oxide film. The transparent electrode 22 can be formed by a method of patterning a conductive metal oxide film formed by a film forming method such as a CVD method or a sputtering method by a patterning method such as an etching method or a lift-off method. The thickness of the transparent electrode 22 is generally in the range of 0.1 to 0.2 μm. The bus electrode 23 is made of a single layer metal film such as aluminum, copper and silver, or a laminated metal film such as chromium / copper / chromium. The bus electrode 23 is formed by a method of applying a metal paste (silver paste) by a screen printing method or a method of patterning a metal film formed by a film forming method such as a sputtering method by a patterning method such as an etching method or a lift-off method. Can be formed. The thickness of the bus electrode 23 is generally in the range of 1 to 10 μm.

  The dielectric layer 26 of the front plate is generally made of low melting point glass. The front plate dielectric layer 26 is formed by applying a dielectric paste by a screen printing method or a coating method using various coaters such as a reverse coater, a curtain coater, a die coater, and a slot coater, and drying and baking the coated film. can do. The thickness of the front plate dielectric layer 26 is generally in the range of 5-20 μm.

  The dielectric protective layer 27 is generally made of magnesium oxide. The dielectric protective layer made of magnesium oxide can be formed by EB vapor deposition. The dielectric protective layer 27 generally has a thickness in the range of 0.5 to 1.0 μm.

  The back plate 30 includes a substrate 31, an address electrode 32 formed on the surface of the substrate 31 on the front plate 20 side, a dielectric layer 33 covering the address electrode 32, and a surface on the front plate side of the dielectric layer 33. The stripe-shaped barrier ribs 34, the blue light-emitting phosphor layer 35B, the green light-emitting phosphor layer 35G and the red light-emitting phosphor layer 35R, and the blue light-emitting phosphor layer 35B and the dielectric layer filled between the barrier ribs 34 are formed. 33 and a wavelength conversion layer 36 inserted between the partition wall 34 and the partition wall 34.

The substrate 31 of the back plate is generally made of a transparent glass substrate.
Address electrodes (also referred to as row electrodes) 32 are arranged in a direction perpendicular to the discharge electrodes 25 of the front plate 20. The address electrode 32 is generally made of a single layer metal film such as aluminum, copper and silver, or a laminated metal film such as chromium / copper / chromium. The address electrode 32 is formed by a method of applying a metal paste (silver paste) by a screen printing method or a method of patterning a metal film formed by a film forming method such as a sputtering method by a patterning method such as an etching method or a lift-off method. Can be formed. The thickness of the address electrode 32 is generally in the range of 1 to 10 μm.

  The dielectric layer 33 of the back plate is generally made of low melting point glass. The back plate dielectric layer 33 is formed by applying a dielectric paste by a screen printing method or a coating method using various coaters such as a reverse coater, curtain coater, die coater, slot coater, etc., and drying and baking the coated film. can do. The thickness of the back plate dielectric layer 33 is generally in the range of 5-20 μm. A white pigment such as titanium oxide may be dispersed in the back plate dielectric layer 33 as a white reflector.

  The partition wall 34 is generally made of low-melting glass. The partition wall 34 can be formed by using a method such as a sandblasting method, an additive method, a photosensitive partition wall forming method (photo method), a lamination printing method, a stamping method, or a transfer method. The size of the partition wall 34 is generally in the range of 100 to 150 μm in height and in the range of 50 to 80 μm in width. The pitch of the partition walls 34 is usually in the range of 110 to 360 nm.

The blue light emitting phosphor layer 35B is made of a CMS: Eu ²⁺ blue light emitting phosphor whose basic composition formula is represented by CaMgSi ₂ O ₆ : Eu ²⁺ . The CMS: Eu ²⁺ blue-emitting phosphor emits blue light when excited by vacuum ultraviolet rays having a wavelength of 220 to 270 nm generated in the wavelength conversion layer 36. The CMS: Eu ²⁺ blue light emitting phosphor has a light emission luminance due to ultraviolet irradiation as compared with the BAM: Eu ²⁺ blue light emitting phosphor widely used as a material of the blue light emitting phosphor layer in the conventional AC type PDP. There is an advantage that the decrease is less likely to occur. The CMS: Eu ²⁺ blue light emitting phosphor is a compound in which a part of calcium of diopside (CaMgSi ₂ O ₆ ) is substituted with europium. The CMS: Eu ²⁺ blue-emitting phosphor preferably has a europium content in the range of 0.005 to 0.1 mol% with respect to the total amount.

The CMS: Eu ²⁺ blue-emitting phosphor comprises a calcium source powder, a europium source powder, a magnesium source powder, and a silicon source powder in a molar ratio of calcium: europium: magnesium: silicon of 0.900 to 0.995: 0. The powder mixture obtained by mixing at a ratio of 100 to 0.005: 1: 1.90 to 2.10 (Ca: Eu: Mg: Si) is brought to a temperature of 1000 to 1500 ° C. in a reducing atmosphere. It can be manufactured by heating and baking.

As an example of the green light emitting phosphor forming the green light emitting phosphor layer 35G, the basic composition formula is Zn ₂ SiO: Mn ²⁺ , (Ba, Sr, Mg) O.αAl ₂ O ₃ : Mn ²⁺ , YBO _3. And phosphors represented by: Tb ³⁺ , (Y, Gd) BO ₃ : Tb ³⁺ , BaAl ₁₂ O ₁₉ : Mn ²⁺ and BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ²⁺ . As an example of the red light-emitting phosphor forming the red light-emitting phosphor layer 35R, the basic composition formulas are YBO ₃ : Eu ³⁺ , (Y, Gd) BO ₃ : Eu ³⁺ , Y ₂ O ₃ : Eu ³⁺ and A phosphor represented by (Y, Gd) ₂ O ₃ : Eu ³⁺ can be given.

  The blue light-emitting phosphor layer 35B, the green light-emitting phosphor layer 35G, and the red light-emitting phosphor layer 35R are pastes in which phosphors of various colors are dispersed by various methods such as screen printing, reverse coater, curtain coater, die coater, and slot coater. It can be formed by coating by a coating method using a coater and drying the coating film. The thickness of each color phosphor layer 35B, 35G, 35R is generally in the range of 1 to 30 μm, preferably in the range of 5 to 20 μm. The green light-emitting phosphor forming the green light-emitting phosphor layer 35G and the red light-emitting phosphor forming the red light-emitting phosphor layer 35R are phosphors that emit light when excited by vacuum ultraviolet rays having a wavelength of 220 to 270 nm. In this case, a wavelength conversion layer made of fluorine-containing magnesium oxide may be interposed between the green light-emitting phosphor layer and the red light-emitting phosphor layer and the dielectric layer 33 and the partition wall 34.

In the present invention, the wavelength conversion layer 36 contains fluorine in the range of 0.01 to 10% by mass, and the magnesium oxide purity is 99.8% by mass or more (provided that the magnesium oxide purity is the total amount excluding the contained fluorine). And a fluorine-containing magnesium oxide having a BET specific surface area in the range of 0.1 to 30 m ² / g. The fluorine-containing magnesium oxide preferably has a fluorine content in the range of 0.03 to 5% by mass, preferably has a magnesium oxide purity of 99.9% by mass or more, and has a BET specific surface area of 0.1 to 0.1%. It is preferably in the range of 12 m ² / g. The purity of magnesium oxide is a value obtained by subtracting from 100 the total content of elements, excluding fluorine and magnesium, contained in 0.001% by mass or more with respect to the total amount of fluorine-containing magnesium oxide powder.

When the wavelength conversion layer 36 made of fluorine-containing magnesium oxide is excited by the Xe resonance line (wavelength 147 nm) and the Xe ₂ molecular beam (wavelength 172 nm) generated by the discharge of the discharge electrode 25 of the front plate 20, the wavelength conversion layer 36 has a wavelength of 220˜. A vacuum ultraviolet ray showing a light emission pattern having a maximum peak in a range of 270 nm is generated. That is, the wavelength conversion layer 36 is not absorbed by the CMS: Eu ²⁺ blue light-emitting phosphor, but the Xe resonance line and the Xe ₂ molecular beam that have passed through the blue light-emitting phosphor layer 35B are vacuum ultraviolet rays having a wavelength of 220 to 270 nm. The blue light emitting phosphor layer 35B is irradiated with the light, and the blue light emitting phosphor layer 35B is excited to emit blue light.

  The wavelength conversion layer 36 is obtained by applying a paste in which fluorine-containing magnesium oxide is dispersed by a screen printing method or a coating method using various coaters such as a reverse coater, a curtain coater, a die coater, or a slot coater, and drying the coated film. Can be formed. The thickness of the wavelength conversion layer 36 is generally in the range of 1 to 10 μm, preferably in the range of 2 to 8 μm.

The fluorine-containing magnesium oxide forming the wavelength conversion layer 36 has a purity of 99.95% by mass or more and a BET specific surface area of 5 to 150 m ² / g, preferably 7 to 50 m ² / g. The raw material powder can be produced by a method comprising firing in the presence of a fluorine source or in an atmosphere of a fluorine-containing gas.

  The magnesium oxide raw material powder used for producing the fluorine-containing magnesium oxide is preferably a magnesium oxide powder produced by a gas phase synthetic oxidation method. The vapor phase synthetic oxidation method is a method for producing a magnesium oxide powder by bringing a metal magnesium vapor and an oxygen-containing gas into contact with each other in the gas phase and oxidizing the metal magnesium vapor.

  As the fluorine source, magnesium fluoride powder is preferably used. The magnesium fluoride powder used as the fluorine source preferably has a purity of 99% by mass or more. When the magnesium oxide raw material powder is fired in the presence of the fluorine source, it is preferable to mix the magnesium oxide raw material powder and the fluorine source before firing.

  As the fluorine-containing gas, it is preferable to use hydrogen fluoride gas or gas obtained by heating and vaporizing magnesium fluoride powder.

  When magnesium oxide raw material powder is baked at a temperature of 850 ° C. or higher for 10 minutes or more in the presence of a fluorine source or in a fluorine-containing gas atmosphere, the primary particles of the magnesium oxide raw material powder grow while incorporating fluorine into the crystal To do. For this reason, the BET specific surface area of the fluorine-containing magnesium oxide powder obtained is lower than that of the magnesium oxide raw material powder. The BET specific surface area of the obtained fluorine-containing magnesium oxide powder is preferably in the range of 1 to 50%, particularly preferably in the range of 3 to 30% with respect to the magnesium oxide raw material powder.

  The firing temperature when firing the magnesium oxide raw material powder in the presence of a fluorine source or in an atmosphere of a fluorine-containing gas is 850 ° C. or higher, preferably 900 to 1500 ° C., particularly preferably 1000 to 1500 ° C. It is in. The firing time is 10 minutes or longer, preferably 20 minutes to 1 hour.

  1 and 2, an example of an AC type PDP in which the wavelength conversion layer 36 is inserted between the blue light emitting phosphor layer 35B, the dielectric layer 33, and the partition wall 34 is shown. In the present invention, It is sufficient that the wavelength conversion layer is interposed between the blue light emitting phosphor layer and the substrate. For example, the wavelength conversion layer may be provided on the address electrode. FIG. 3 shows a cross-sectional view of an example of an AC type PDP according to the present invention in which a wavelength conversion layer is provided on the address electrode. In FIG. 3, the same components as those of the AC type PDP shown in FIGS. 1 and 2 are denoted by the same reference numerals as those in FIGS. 1 and 2, and the description thereof is omitted.

  The AC type PDP shown in FIG. 3 has a dielectric layer formed on the address electrode of the AC type PDP shown in FIGS. 1 and 2 as a wavelength conversion layer, a blue light emitting phosphor layer, a dielectric layer, a partition wall, The wavelength conversion layer inserted between the layers is omitted. In the AC type PDP shown in FIG. 3, the wavelength conversion layer 40 made of fluorine-containing magnesium oxide formed so as to cover the address electrode layer may be formed of fluorine-containing magnesium oxide alone, or fluorine-containing magnesium oxide and You may form as a mixture with white pigments, such as a titanium oxide. Moreover, you may form the wavelength conversion layer 40 in the form which disperse | distributed fluorine-containing magnesium oxide to the low melting glass. When a wavelength conversion layer is formed by dispersing fluorine-containing magnesium oxide in a low-melting glass, the content of fluorine-containing magnesium oxide in the wavelength conversion layer is generally in the range of 1 to 30% by mass, preferably 5 to 20% by mass. It is in the range.

  The wavelength conversion layer 40 is obtained by applying a paste in which fluorine-containing magnesium oxide is dispersed by a screen printing method or a coating method using various coaters such as a reverse coater, a curtain coater, a die coater, or a slot coater, and drying the coated film. Can be formed. The thickness of the wavelength conversion layer 40 is generally in the range of 5 to 20 μm.

[Example 1]
(1) Production of Fluorine-Containing Magnesium Oxide Paste Magnesium oxide produced by a gas phase synthetic oxidation method (2000A, manufactured by Ube Materials Co., Ltd., purity: 99.98% by mass, BET specific surface area: 8.7 m ² / g ) 5 g and magnesium fluoride (purity: 99.1 mass%, BET specific surface area: 6.4 m ² / g) were mixed to obtain a powder mixture. The obtained powder mixture was put into an alumina crucible having a capacity of 25 mL, covered and placed in an electric furnace, heated to 1200 ° C. at a heating rate of 240 ° C./hour, and then baked at the temperature for 30 minutes. Thereafter, the furnace temperature was cooled to room temperature at a temperature lowering rate of 240 ° C./hour. The obtained fired product was fluorine-containing magnesium oxide having a BET specific surface area of 1.81 m ² / g, a fluorine content of 0.0496% by mass, and a purity of magnesium oxide of 99.9% by mass or more.

  2.5 g of the fluorine-containing magnesium oxide obtained as described above was added to a paste prepared by adding 21 g of ethyl cellulose to 300 mL of isopropyl alcohol and stirred for 15 hours with a magnetic stirrer. Mixing for minutes, a fluorine-containing magnesium oxide paste was prepared.

(2) Production of CMS: Eu ²⁺ blue light emitting phosphor paste Calcium carbonate powder (purity: 99.99% by mass, average particle diameter measured by laser diffraction scattering method: 3.87 μm), europium oxide powder (purity: 99.9% by mass, average particle diameter measured by laser diffraction scattering method: 2.71 μm, magnesium oxide (produced by gas phase oxidation reaction, purity 99.99% by mass, average converted from BET specific surface area Particle diameter: 0.05 μm), and silicon dioxide powder (purity: 99.9 mass%, average particle diameter measured by laser diffraction scattering method: 3.87 μm), and the molar ratio of Ca: Eu: Mg: Si is 0.98: 0.02: 1: 2.00, respectively, and wet-mixed in an ethanol solvent for 24 hours using a ball mill. The resulting powder mixture was dried and the ethanol was evaporated. The dried powder mixture was put in an alumina crucible and fired at a temperature of 1050 ° C. for 3 hours in a mixed gas atmosphere of 2 volume% hydrogen-98 volume% argon. The obtained fired product was further heated in the atmosphere at a temperature of 600 ° C. for 1 hour while being put in an alumina crucible. The obtained fired product was a CMS: Eu ²⁺ blue-emitting phosphor having a diopside crystal structure.

Add 2.5 g of CMS: Eu ²⁺ blue-emitting phosphor obtained as described above to a paste prepared by adding 21 g of ethylcellulose to 300 mL of isopropyl alcohol and stirring for 15 hours with a magnetic stirrer, and defoaming A CMS: Eu ²⁺ blue-emitting phosphor paste was prepared by mixing for 7 minutes using a machine.

(3) Manufacture of a laminate having a CMS: Eu ²⁺ blue light-emitting phosphor layer formed on a substrate via a fluorine-containing magnesium oxide layer on a quartz substrate having a diameter of 19.8 mm and a thickness of 2.0 mm. The magnesium oxide paste was applied with a screen printer, dried at a temperature of 70 ° C., and then annealed at a temperature of 580 ° C. for 1 hour to form a fluorine-containing magnesium oxide layer having a thickness of 4 μm. Next, a CMS: Eu ²⁺ blue light emitting phosphor paste is applied on the fluorine-containing magnesium oxide layer by a screen printer, dried at a temperature of 70 ° C., and then annealed at a temperature of 580 ° C. for 1 hour. A CMS: Eu ²⁺ blue light-emitting phosphor layer having a thickness of 6 μm was formed (the total layer thickness of the fluorine-containing magnesium oxide layer and the CMS: Eu ²⁺ blue light-emitting phosphor layer was 10 μm).

CMS: Eu ²⁺ blue light emitting phosphor layer of the obtained laminated plate is irradiated with vacuum ultraviolet rays having a wavelength of 146 nm and a wavelength of 172 nm and excited by vacuum ultraviolet rays having a wavelength of 146 nm and a wavelength of 172 nm using a spectrofluorometer. The emission spectrum of blue light was measured. Table 1 below shows the maximum peak value of the obtained emission spectrum as the maximum luminance.

[Comparative Example 1]
The CMS: Eu ²⁺ blue light-emitting phosphor paste prepared in Example 1 was applied to a quartz substrate having a diameter of 19.8 mm and a thickness of 2.0 mm with a screen printer, dried at a temperature of 70 ° C., and then 580 ° C. A laminated plate in which a CMS: Eu ²⁺ blue light emitting phosphor layer having a thickness of 10 μm was formed on a substrate was manufactured by annealing at a temperature of 1 hour.

The CMS: Eu ²⁺ blue light-emitting phosphor layer of the obtained laminated plate was irradiated with vacuum ultraviolet rays having a wavelength of 146 nm and a wavelength of 172 nm in the same manner as in Example 1, and blue light generated by vacuum ultraviolet excitation at a wavelength of 146 nm and a wavelength of 172 nm was emitted. The emission spectrum was measured. Table 1 below shows the maximum peak value of the obtained emission spectrum as the maximum luminance.

[Reference Example 1]
Add 2.5 g of BAM: Eu ²⁺ blue-emitting phosphor to 300 ml of isopropyl alcohol, add 21 g of ethylcellulose, and stir with a magnetic stirrer for 15 hours, and mix for 7 minutes using a defoamer. A BAM: Eu ²⁺ blue-emitting phosphor paste was prepared.
A BAM: Eu ²⁺ blue light-emitting phosphor paste prepared as described above was applied to a quartz substrate having a diameter of 19.8 mm and a thickness of 2.0 mm with a screen printer, and dried at a temperature of 70 ° C. Annealing was performed at a temperature of 1 ° C. for 1 hour to produce a laminate having a 10 μm thick BAM: Eu ²⁺ blue light emitting phosphor layer formed on the substrate.

The BAM: Eu ²⁺ blue light-emitting phosphor layer of the obtained laminated plate was irradiated with vacuum ultraviolet rays having a wavelength of 146 nm and a wavelength of 172 nm in the same manner as in Example 1, and the blue light generated by the vacuum ultraviolet excitation at the wavelengths of 146 nm and 172 nm was irradiated. The emission spectrum was measured. Table 1 below shows the maximum peak value of the obtained emission spectrum as the maximum luminance.

Table 1
────────────────────────────────────────
Excitation wavelength 146 nm Excitation wavelength 172 nm
Maximum brightness at Maximum brightness at ─────────────────────────────────────────
Example 1 (CMS: Eu ²⁺ + MgO: F) 129 152
────────────────────────────────────────
Comparative Example 1 (CMS: Eu ²⁺ ) 100 100
Reference Example 1 (BAM: Eu ²⁺ ) 105 200
────────────────────────────────────────
The values in Table 1 are relative values with the maximum luminance obtained in Comparative Example 1 as 100.

Table as 1 to indicate apparent from the results, CMS formed via a fluorine-containing magnesium oxide layer: Eu ²⁺ blue-emitting phosphor layer (Example 1), CMS: Eu ²⁺ blue-emitting phosphor layer alone It can be seen that the luminance is improved in any vacuum ultraviolet ray having a wavelength of 146 nm and a wavelength of 172 nm as compared with (Comparative Example 1). Compared with the BAM: Eu ²⁺ blue light emitting phosphor layer alone (Reference Example 1), the luminance is high for vacuum ultraviolet rays having a wavelength of 146 nm, which is mainly generated from the discharge gas in the normal AC type PDP. You can see that

It is a perspective view of an example of AC type PDP according to the present invention. It is the sectional view on the AA line of AC type PDP shown in FIG. It is sectional drawing of another example of AC type PDP according to this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Discharge space 20 Front plate 21 Transparent glass substrate 22 Transparent electrode 23 Bus electrode 24a, 24b Column electrode 25 Discharge electrode 26 Dielectric layer 27 Dielectric protective layer 30 Back plate 31 Substrate 32 Address electrode 33 Dielectric layer 34 Partition 35B Blue light emission Phosphor layer 35G Green light emitting phosphor layer 35R Red light emitting phosphor layer 36 Wavelength conversion layer 40 Wavelength conversion layer

Claims (10)

On the substrate, fluorine is contained in the range of 0.01 to 10% by mass, and the purity of magnesium oxide is 99.8% by mass or more (however, the purity of magnesium oxide includes magnesium oxide in the total amount excluding the contained fluorine) The basic composition formula is expressed as CaMgSi ₂ O ₆ : Eu ²⁺ through a wavelength conversion layer made of fluorine-containing magnesium oxide having a BET specific surface area in the range of 0.1 to 30 m ² / g. A back plate for an alternating current plasma display panel in which a blue light emitting phosphor layer made of a blue light emitting phosphor is formed.   The back plate according to claim 1, wherein the wavelength conversion layer has a thickness in the range of 1 to 10 μm.   The back plate according to claim 1, wherein the blue light emitting phosphor layer has a thickness in the range of 1 to 30 μm.   The back plate according to claim 1, wherein the fluorine content of the fluorine-containing magnesium oxide is in the range of 0.03 to 5 mass%.   The back plate according to claim 1, wherein the magnesium oxide purity of the fluorine-containing magnesium oxide is 99.9% by mass or more. The back plate according to claim 1, wherein the fluorine-containing magnesium oxide has a BET specific surface area of 0.1 to 12 m ² / g.   The back plate according to claim 1, wherein an address electrode is formed on the substrate, and a blue light emitting phosphor layer is formed on the address electrode via a wavelength conversion layer.   The address electrode and a dielectric layer covering the address electrode are formed on the substrate, and a blue light emitting phosphor layer is formed on the dielectric layer via a wavelength conversion layer. The back plate as described.   The back plate according to claim 1, wherein a partition wall is formed on the substrate, and a blue light emitting phosphor layer is also formed on a wall surface of the partition wall via a wavelength conversion layer.   A front plate on which a discharge electrode is formed via a discharge space filled with a discharge gas containing Xe gas, and the back plate according to any one of claims 1 to 9, comprising a discharge electrode, An AC type plasma display panel which is disposed so that the blue light emitting phosphor layers face each other.

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