JP2000323050A - Gas discharge display panel and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas discharge display panel of a long life provided with a negative electrode of good conductivity and excellent sputtering resistance capable of discharging stably with a low voltage on an entire screen. SOLUTION: This gas discharge display panel includes a positive electrode 11 and a negative electrode 12 exposed in a discharge space and oppositely arranged at a discharge interval, and seals the positive and negative electrodes in an air-tight container with gas capable of ionizing. At least one of the negative electrode 12 and the positive electrode 11 contains boride compound of a rear earth element and metal oxide. The boride compound of a rear earth element is at least one of hexaboride and tetraboride La, Gd, Y, Nd, and Ce, and the metal oxide contains at least one of MgO, Y2O3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a gas discharge display panel of a DC drive type and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in a gas discharge display panel of a DC drive type, a conductive material such as Ni or A1 has been used as a cathode. Recently, LaB ₆ and BaA1 _2, which is an insulator, are applied to the surface of a cathode substrate made of a conductive material by plasma spraying.
0 ₄ contaminating the cathode material covering the structure (JP-7-
No. 230770), a structure of a cathode in which an insulator such as MgO or Y ₂ O ₆ is formed in an island shape on the surface of a cathode base made of a conductive material (JP-A-7-85800), and a cathode base made of a conductive material. A structure of a cathode having a surface coated with a single element material of Al, Cr, Ta, and W (Japanese Patent Application Laid-Open No. 8-335439) has been proposed.

FIG. 3 is a schematic view showing the structure of the conventional gas discharge display panel. This gas discharge display panel is a plasma addressed display device (JP-A-1-217396), and shows an example in which a single-layer structure of Ni, which is a conductive material, is used for a cathode. This gas discharge display panel has a thickness of 50 μm interposed between the display cell 1 and the discharge cell 2.
It has a flat panel structure in which a common thin glass 3 made of m glass sheets is laminated.

The display cell 1 has a front plate 4 made of transparent glass.
A front plate 4 in which a color filter and a signal electrode 7 (not shown) are sequentially laminated on one surface;
The thin glass 3 provided on one side of the front plate 4 is adhered at a predetermined interval via a spacer 15, and the gap is filled with the liquid crystal layer 6. The signal electrode 7 has, for example, an ITO electrode material made of, for example, indium oxide / tin oxide, arranged in a direction orthogonal to the partition walls 8 of the discharge cell, immediately above each dye row of the color filter, and has substantially the same size as each dye row. As described above, after being formed on the color filter by, for example, an evaporation method or a sputtering method, it is patterned by photolithography.

The discharge cells 2 are made of a back plate 5 made of transparent glass.
The anode 11 and the cathode 12 are formed on the back plate 5 so as to be exposed in the discharge space 10. The partition 8 is formed along the anode 11. Further, in the state where one surface of the front plate 4 and one surface of the back plate 5 face each other at the peripheral portion, the thin glass 3 is used with the back plate 5 having a plurality of partitions 8, the anode 11, and the cathode 12 formed on one surface and a sealing material 9. And hermetically bonded.

On the other surface of the front plate 4 and the back plate 5 opposite to the one surface, polarizing plates (not shown) are provided which are orthogonal to each other.

As described above, in the gas discharge display panel, the back plate 5 and the front plate 4 are connected to each other via the thin glass 3, and a plurality of discharge spaces formed by the thin glass 3, the back plate 5, and the plurality of partition walls 8. It is manufactured by encapsulating an ionizable gas in 10. Further, for example, helium, neon, argon, xenon, and a mixed gas thereof are sealed as ionizable gas species.

In the above configuration, for example, the discharge space 1
When a predetermined voltage is applied to the anode 11 and the cathode 12 corresponding to 0, the anode 11 and the cathode 12 become the anode and the cathode 12, respectively.
Acting as a cathode, the gas in the discharge space 10 is selectively ionized to generate a plasma discharge, and the inside thereof is maintained at a substantially anode potential. When a data voltage is applied to the signal electrode 7 in this state, the data voltage is written to the liquid crystal layer 6 of the pixel corresponding to the discharge space 10 via the thin glass 3. When the plasma discharge ends, the discharge space 1
0 becomes a floating potential, and the voltage written in the liquid crystal layer 6 of the corresponding pixel is held until the next writing period (for example, after one frame). At this time, the discharge space 10 functions as a sampling switch, and the liquid crystal layer 6 of each pixel functions as a sampling capacitor. Since the liquid crystal operates with the data voltage written from the signal electrode 7 to the liquid crystal layer 6 of each pixel, display is performed in pixel units. Accordingly, a two-dimensional image can be displayed by sequentially scanning a pair of discharge spaces in which data voltages are written to the liquid crystal layers 6 of a plurality of pixels arranged in the column direction by generating a plasma discharge in the row direction. .

FIG. 4 is a schematic view showing the structure of the conventional gas discharge display panel. This gas discharge display panel is D
C-drive type plasma display panel (JP-A-8-3
No. 35439, hereinafter referred to as DC-PDP), in which Ag is used for a lower layer and Al is used for an upper layer as a cathode material.
2 shows an example of a layer structure. In this gas discharge display panel, a flat back plate 5 and a front plate 4 made of glass are disposed parallel to and opposed to each other, and the substrates 4 and 5 are separated at a predetermined interval by a partition wall 8 provided therebetween. Is held.
Further, a cathode 12 is provided on the back side of the front plate 4, and the cathode is a bus electrode 13 and a coating electrode 14.
It has a layered structure. An anode 11 is provided on the front side of the back plate 5 so as to be perpendicular to the cathode 12. Further, phosphors 16 corresponding to the respective emission colors are formed on the wall surfaces of the back plate 5 and the partition walls 8. Therefore, front panel 4
, A discharge space 10 surrounded by the back plate 5 and the partition 8, and an ionizable gas is sealed in the discharge space 10.
Further, for example, helium, neon, argon, xenon, and a mixed gas thereof are sealed as ionizable gas species.

In this DC-PDP, a discharge is performed by applying a predetermined voltage from a DC power supply (not shown) between a cathode and an anode. Then, the phosphor 16 is excited by the ultraviolet light generated by the discharge, and light having a luminescent color corresponding to the type of the phosphor is transmitted through the front plate 4 and emitted to the outside. As a result, a two-dimensional image is displayed on the front panel 4 as a display surface.

[0011]

The structure of a discharge cell of a conventional DC-driven gas discharge display panel has the following problems.

(1) In a single-layer structure in which a conductive material such as Ni, Al, or Ag is used for the cathode (Japanese Patent Application Laid-Open No. 1-217396), the resistance of the cathode can be reduced due to the problem of voltage drop when voltage is applied. Since it is necessary, it is difficult to select a material having excellent sputter resistance and secondary electron emission efficiency. Therefore, since the above-mentioned material is weak to ion bombardment, spattering at the time of discharge is intense, and the change over time in discharge characteristics due to spatter is large. Further, the metal and glass components of the cathode are scattered by the ion bombardment on the back plate and the thin glass, resulting in a decrease in transmittance. The above problems caused by sputtering can be reduced by adding mercury, but it is hard to say that sufficient characteristics such as local spattering due to uneven distribution of mercury have been obtained. Also, mercury is harmful and cannot be used because environmental pollution at the time of disposal is a problem particularly when the gas discharge panel is enlarged.

(2) The cathode has a two-layer structure of a bus electrode and a coating electrode, and the bus electrode is made of a conventional low-resistance material such as Ni, Al, Ag or the like, and the coating electrode is excellent in sputter resistance and secondary electron emission efficiency. In a structure using a material (JP-A-7-230770 and JP-A-8-335439), when the material of the coated electrode is a boride compound of a rare earth element such as LaB ₆ , LaB ₆ particles have conductivity. Although good, the resistance of the coated electrode layer is close to the insulating state because an insulating oxide film is easily formed on the particle surface. Therefore, the LaB ₆ particles are locally activated during the initial aging, and the localization of the discharge is apt to occur. In the localized portion of the discharge, deterioration of the cathode due to sputtering is promoted.

Recently, it has been disclosed that a material in which LaB ₆ is mixed with BaAL ₂ O ₄ as an insulator is used for a coated electrode (Japanese Patent Application Laid-Open No. 7-230770). This reduces the discharge current by lowering the conductivity of the entire coated electrode, thereby suppressing the influence of sputtering. In particular, the mixed material when coated by plasma spraying method, since the BaAl ₂ O ₄ is an insulating material to produce a superior BaO and Ba in the secondary electron emission efficiency than LaB _6, it consists only of LaB ₆ The discharge voltage is lower than that of the cathode.

However, the formation by the plasma spraying method requires a special apparatus, and the process becomes complicated because patterning by photolithography is required for lift-off. In the plasma spraying method, LaB ₆ and BaAL ₂ O ₄ are used because an inert gas flows into a plasma spray gun to generate an arc discharge to form a high-speed jet and supply the electrode material in the jet to adhere to the substrate. When a mixture of two types of electrode materials is applied as described above, the distribution of both particles on the coated surface is uneven, and the uniformity of discharge is lacking. These problems can be solved by the screen printing method. However, in a screen printing method, the mixed substance composed of LaB ₆ and BaAL ₂ O _{4 has a} disadvantage that the B
Since aO and Ba are not generated and BaAL ₂ O ₄ itself does not have a large difference in secondary electron emission efficiency as compared with LaB ₆ , the effect of lowering the discharge voltage is smaller than that of LaB ₆ alone. Not much different. Therefore, there is a case where there is no effect of lowering the discharge voltage due to the process of applying the coated electrode.

Since BaAL ₂ O ₄ is inferior to MgO or Y ₂ O ₃ in spatter resistance, when the occupation ratio of the coating electrode is increased, MgO or Y ₂ O ₄ is substituted for BaAL ₂ O _4.
Compared to a coated electrode mixed with O ₃ , it is more susceptible to sputtering. As a result, a change with time in the discharge characteristics is large, and the metal or glass component of the cathode is scattered to the back plate or the thin glass, which tends to lower the transmittance.

When the material of the coated electrode as disclosed in JP-A-8-335439 is a single element material of Al, Cr, Ta, and W, the above material is compared with other single element materials such as Ag, Au, and Ni. and although excellent sputtering resistance and secondary electron emission efficiency, when compared to compounds such as LaB ₆ and GdB ₆ described above, the voltage reduction of the discharge voltage for poor sputtering resistance and secondary electron emission efficiency Less effective and easily affected by sputtering.

(3) A structure in which an insulating material having excellent sputter resistance or secondary electron emission efficiency is formed in an island shape on a conventional bus electrode made of a low-resistance material such as Ag, Ni, or Al ( Japanese Unexamined Patent Publication No. 7-85800) has a structure in which a crack is generated in an insulating material due to a difference in thermal expansion coefficient between a low-resistance material and an insulating material. In addition, when the manufacturing apparatus is formed by a screen printing method which is inexpensive and the process is easy, it is very difficult to form cracks finely and uniformly like a thin film formed by plasma spraying or vapor deposition due to the property of a thick film. It is. Furthermore, in the printing method, local discharge at the exposed portion of the bus electrode, which is considered to be caused by the non-uniformity of cracks, has been confirmed, and deterioration of the cathode due to sputtering has been promoted at the location where the local discharge has occurred.

The present invention has been made in view of the above problems, and has as its object the purpose of BaAL ₂ O _4.
Insulation material itself has high secondary electron emission efficiency and excellent sputter resistance characteristics instead of exhibiting excellent secondary electron emission efficiency by generating BaO or Ba as in And a mixed material of a boride compound of a rare earth element having good conductivity by applying a conventional method (Japanese Unexamined Patent Publication No.
No. 30770), it is effective in lowering the discharge voltage irrespective of the coating process while reducing the discharge current and suppressing the influence of sputtering, and has excellent sputter resistance as compared with the conventional cathode. As a result, it is possible to provide a long-life gas discharge display tube that discharges the entire screen stably at a low voltage without adding mercury into the discharge cells.

[0020]

According to the gas discharge display panel of the present invention, an anode and a cathode exposed in a discharge space are arranged opposite to each other with a discharge interval therebetween, and sealed together with an ionizable gas in an airtight container. Gas discharge display panel
At least one of the cathode and the anode contains a mixed substance of a boride compound of a rare earth element and a metal oxide, and the boride compound of the rare earth element is hexaboride and tetraboride of La, Gd, Y, Nd, and Ce. And the metal oxide contains at least one of MgO and Y ₂ O ₃ , and the above-mentioned problem is solved.

Preferably, the particle size of the boride compound of the rare earth element and the metal oxide is in the range of 0.5 to 15 μm.

Preferably, the gas discharge display panel is a plasma addressed display panel having a liquid crystal layer.

Preferably, at least one of the cathode and the anode is a paste containing the boride compound and the metal oxide, and an electrode is formed by a screen printing method.

Preferably, in the production of the gas discharge display panel by the screen printing method, the content of the organic metal or the glass frit functioning as a binder is in the range of 1 to 30% by weight based on the paste.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a gas discharge display panel according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the dimensional ratio of each part in the drawings is not always accurate.

FIG. 1 shows a first embodiment in which the present invention is applied to a plasma addressed display device. A method for forming a discharge cell according to the present invention will be described. Although display cells actually exist on the thin glass 3, FIG. 1 omits the display cells.

In the method of forming a discharge cell of a gas discharge display tube shown in FIG. 1, first, an anode 11 and a bus electrode 13 are formed on an electrode paste (DuPont) containing Ni as a main component on a back plate 5 which has been cleaned and annealed. 9538)
After forming by screen printing method, 1
Hold at 40 ° C. for 10 minutes and dry. In this embodiment, two-layer printing is performed, and the bus electrode has a width of 100 μm and a thickness of 40 μm.
m, the anode had a width of 400 μm and a film thickness of 40 μm. Although Ni is used as the material, a conventional conductive material such as aluminum, silver, and silver-palladium can also be used. Note that the bus electrode may be formed by forming a thin film by a vapor deposition method, a sputtering method, or the like, and then using a conventional forming method such as patterning by photoetching or sandblasting.

Further, after forming the anode 11 and the bus electrode 13, the coating electrode 14 is coated with a screen printing method and then dried at 140 ° C. for 10 minutes in a belt type drying furnace. In this embodiment, two-layer printing is performed and the width 1
50 μm and a film thickness of 20 μm were obtained. As the material, the metal particle component is composed of a mixture of a rare earth element boride compound and a metal oxide, and the rare earth element boride compound is
It is possible to use a mixed material comprising at least one of hexaboride or tetraboride of La, Gd, Y, Nd and Ce, and wherein the metal oxide is at least one of MgO or Y ₂ O _3. Here, a mixture of the above-mentioned rare earth element boride compound, which is a mixture of GdB ₆ having excellent sputter resistance and Y ₂ O ₃ which is a metal oxide having a low deliquescent property, is used.

In the method of forming the coated electrode 14, this embodiment does not require an expensive and complicated apparatus, and can be formed by a simple process, and the mixed substance can be uniformly dispersed. However, the embodiment of the present invention is not limited to this, in addition to screen printing, sandblasting, vapor deposition, electrodeposition, sputtering, using a conventional forming method such as thermal spraying method Good. In this embodiment, the cathode 12 is composed of the bus electrode 13 and the covering electrode 14.
, But the anode 11 may have a similar structure. Hereinafter, the paste composition of the above mixed substance by the screen printing method will be described.

The paste comprises a mixture of a metal particle component, an organic metal which functions as a binder and becomes a metal oxide by firing, or a glass frit, a solvent, and an organic additive of a resin.

The metal particles are made of a mixture of a rare earth element boride compound and a metal oxide, and the rare earth element boride compound is La, Gd, Y, Nd, Ce hexaboride or tetraboride. At least one kind, wherein the metal oxide is a mixture of at least one kind of MgO or Y ₂ O ₃ . The mixing ratio of the above mixture is not particularly limited as long as the cathode after firing has a sufficient conductivity. The content of the mixture of metal particles with respect to the paste may be within a range that functions as a cathode.

As the organic metal, an alkoxide or carboxylate of an alkaline earth metal element, an alkali metal element, or a rare earth element can be selected, and a metal oxide formed by firing the organic metal functions as a binder. In addition, it may also serve as a cathode.

The above-mentioned glass frit is made of various glasses such as lead borosilicate glass or bismuth borosilicate glass containing borate and silicate as main components and containing at least one kind of lead, sulfur, selenium, bismuth and the like. Can be used. The metal particles or glass frit preferably has a particle size of several tens of microns to sub-micron. In general, the particle size of metal particles, printability by screen printing (FIG. 5A), adhesion (FIG. 5B), and resistance change due to oxidation of a rare earth element boride compound in a firing atmosphere (FIG. 5C) are shown in FIG. The relationship is shown in If the particle size of the metal particles is 15 μm or more, especially when the pattern width is reduced to 5 μm or more, clogging of the printing plate becomes easy to occur, and the reproducibility of the shape deteriorates (FIG. 5A).
Regarding the adhesion, if the thickness is 0.5 μm or less or 15 μm or more, the film quality becomes brittle and the adhesion is impaired (FIG. 5).
B). As a result of considering these conditions, the particle size of the metal particles was selected in the range of 0.5 to 15 μm. Further, as can be understood from FIG. 5, the boride compound of a rare earth element having a particle size of 6 μm or more does not easily cause an increase in resistance due to oxidation even at the temperature of the firing atmosphere (FIG. 5C), and the initial conditioning is easy. 6 when thinning is not considered
The range of about 15 μm is more desirable. Since the organic metal exists in a liquid state in the paste, the dispersibility of the particles is superior to that in which glass frit is mixed. When the content of the organic metal and the glass frit is 1% by weight or less with respect to the paste, the adhesion between the particles or between the particles and the back plate is impaired. The content is desirably in the range of 1 to 30% by weight because of the reduction and the impairment of the characteristics as a cathode.

Further, examples of the organic additives to be added to the above-mentioned paste include urea resin, melamine resin, phenol resin, epoxy resin, unsaturated polyester, alkyd resin, urethane resin, ebonite, and polysiloxy silicate. The content of the organic additive is required to prevent the viscosity from increasing in order to maintain the fluidity and moldability of the mixture with the glass or metal particles, while the content is not sufficient during curing after drying. It is desirable to have shape retention. From such a point, the content of the organic additive is 0.5% by weight or more based on the above-mentioned paste, and 20% by weight or more.
% By weight or less is desirable.

The solvent to be added to the paste is not particularly limited as long as it is compatible with the organic additive. For example, aromatic solvents such as toluene, xylene, benzene and phthalic acid ester can be used. Solvents, higher alcohols such as hexanol, octanol, decanol and oxyalcohol, and esters such as acetic acid ester and glyceride can be used. Furthermore, in order to volatilize the solvent slowly, it is also possible to use two or more of the above solvents in combination. In addition, the content of the solvent is required to be 0.1% by weight or more based on the above-mentioned paste, and in order to maintain the fluidity and moldability of the mixture with glass or metal particles, a glass frit or an organic metal and It is desirable to reduce the viscosity of the mixture of particles and organic additives to some extent. From such a point, it is desirable that the content of the solvent is 0.1% by weight or more and 35% by weight or less based on the paste.

From the above, the composition of the above-mentioned first strike is GdB having an average particle diameter of 6 μm as a metal component with respect to the above-mentioned first strike.
₆ powder 20% by weight, average particle diameter 6 μm Y ₂ O ₃ powder 4
A glass frit containing 0% by weight, 5% by weight of bismuth borosilicate glass having an average particle size of 8 μm, 12.5% by weight of terpineol and diethylene glycol dibutyl ether, and 10% by weight of a cellulose resin is used.

Next, the partition wall 8 is made of a thick-film insulating paste containing a low-melting glass and an appropriate filler (Okuno Pharmaceutical Co., Ltd. G3-21).
25), and after forming by screen printing method,
It is dried by holding at 140 ° C. for 10 minutes in a belt type drying furnace. In this embodiment, eight-layer printing was performed to obtain a film thickness of 160 μm. The partition may be formed by a conventional method such as a sand blast method.

After that, the front plate 4 and the back plate 5 are baked at a predetermined temperature in a range that does not cause thermal deformation, here 585 ° C., so that the partition wall 8, the anode 11 and the cathode 12 are formed. However, the arrangement, film thickness, and dimensions of the anode, the cathode, and the partition wall are not limited to these, and may be the same as conventional discharge cell shapes having various structures. In addition, here, the firing is performed all at once after forming the cathodes, anodes, and partition walls, which are the discharge cell components. However, firing may be performed individually each time each discharge cell component is formed.

Thereafter, the thin glass 3 which has been washed and annealed is overlaid, and the periphery thereof is sealed with a sealing material 9 such as a low-melting glass.
And airtightly joined. Further, an ionizable gas is sealed in the discharge space 10 to complete the discharge cell 2. In this embodiment, xenon is used as the ionizable gas species, but helium, neon, argon, xenon, or a mixed gas thereof may be filled. This discharge cell has D
Although it becomes a C-drive type plasma addressed display device, it is manufactured in the same manner as the prior art except for the cathode structure and manufacturing method for the discharge cell described above.

As a second embodiment, an example in which the present invention is applied to a DC-PDP will be described. In the manufacturing method of the gas discharge display panel shown in FIG. 2, the bus electrode 13 was formed on the front plate 4 which had been washed and annealed by using a screen paste method using an electrode paste containing Ag as a main component (Namics XFP5392). After that, 140 in belt type drying furnace
Hold at 0 ° C. for 10 minutes and dry. In this embodiment, two-layer printing was performed to obtain a width of 100 μm and a film thickness of 40 μm. Other bus electrode materials such as aluminum, nickel,
Conventional conductive materials such as silver and silver-palladium can also be used. Note that the bus electrode may be formed by forming a thin film by a vapor deposition method, a sputtering method, or the like, and then using a conventional forming method such as patterning by photoetching or sandblasting. After that, the coating electrode 14 is formed by forming a coating by a screen printing method after forming the bus electrode 13, and then dried by holding at 140 ° C. for 10 minutes in a belt-type drying furnace. In this embodiment, two-layer printing is performed and the width is 150 μm.
m and a film thickness of 20 μm. As the material, the metal particle component is composed of a mixture of a boride compound of a rare earth element and a metal oxide, and the boride compound of the rare earth element is La, G
d, Y, Nd, Ce, at least one of hexaboride or tetraboride, and the metal oxide is Mg
A mixture of at least one of O and Y ₂ O ₃ can be used. In this case, the above-mentioned rare earth element boride compound has excellent sputter resistance GdB ₆ and the above metal oxide has low deliquescent property Y _A mixture of ₂ O ₃ is used.

In the method of forming the coated electrode 14, this embodiment does not require an expensive and complicated apparatus, can be formed by a simple process, and can uniformly disperse the mixed substance. Although formed, the embodiment of the present invention is not limited to this, in addition to screen printing, sandblasting, vapor deposition, electrodeposition, sputtering, using a conventional forming method such as thermal spraying Is also good. In this embodiment, the cathode 12 is composed of the bus electrode 13 and the covering electrode 14.
, But the anode 11 may have a similar structure. Hereinafter, the paste composition of the above mixed substance by the screen printing method will be described.

The paste comprises a mixture of a metal particle component, an organic metal which functions as a binder and becomes a metal oxide upon firing, or a glass frit, a solvent, and an organic additive of a resin.

The metal particles are composed of a mixture of a rare earth element boride compound and a metal oxide, and the rare earth element boride compound is composed of La, Gd, Y, Nd, Ce hexaboride or tetraboride. At least one kind, wherein the metal oxide is a mixture of at least one kind of MgO or Y ₂ O ₃ . The mixing ratio of the above mixture is not particularly limited as long as the cathode after firing has a sufficient conductivity. The content of the mixture of metal particles with respect to the paste may be within a range that functions as a cathode.

As the organic metal, an alkoxide or carboxylate of an alkaline earth metal element, an alkali metal element, or a rare earth element can be selected, and a metal oxide produced by firing the organic metal functions as a binder. In addition, it may also serve as a cathode.

The above-mentioned glass frit is made of various glasses such as lead borosilicate glass or bismuth borosilicate glass containing borate and silicate as main components and containing at least one kind of lead, sulfur, selenium, bismuth and the like. Can be used. The metal particles or glass frit preferably has a particle size of several tens of microns to sub-micron. In general, the particle size of metal particles, printability by screen printing (FIG. 5A), adhesion (FIG. 5B), and resistance change due to oxidation of a rare earth element boride compound in a firing atmosphere (FIG. 5C) are shown in FIG. The relationship is shown in If the particle size of the metal particles is 15 μm or more, especially when the pattern width is reduced to 5 μm or more, clogging of the printing plate becomes easy to occur, and the reproducibility of the shape deteriorates (FIG. 5A).
Regarding the adhesion, if the thickness is 0.5 μm or less or 15 μm or more, the film quality becomes brittle and the adhesion is impaired (FIG. 5).
B). As a result of considering these conditions, the particle size of the metal particles was selected in the range of 0.5 to 15 μm. Further, as can be understood from FIG. 5, the boride compound of a rare earth element having a particle size of 6 μm or more does not easily cause an increase in resistance due to oxidation even at the temperature of the firing atmosphere (FIG. 5C), and the initial conditioning is easy. 6 when thinning is not considered
The range of about 15 μm is more desirable. Since the organic metal exists in a liquid state in the paste, the dispersibility of the particles is superior to that in which glass frit is mixed. When the content of the organic metal and the glass frit is 1% by weight or less with respect to the paste, the adhesion between the particles or between the particles and the back plate is impaired. The content is desirably in the range of 1 to 30% by weight because of the reduction and the impairment of the characteristics as a cathode.

Further, examples of the organic additives to be added to the above-mentioned paste include urea resin, melamine resin, phenol resin, epoxy resin, unsaturated polyester, alkyd resin, urethane resin, ebonite, and polysiloxy silicate. The content of the organic additive is required to prevent the viscosity from increasing in order to maintain the fluidity and moldability of the mixture with the glass or metal particles, while the content is not sufficient during curing after drying. It is desirable to have shape retention. From such a point, the content of the organic additive is 0.5% by weight or more based on the above-mentioned paste, and 20% by weight or more.
% By weight or less is desirable.

The solvent to be added to the paste is not particularly limited as long as it is compatible with the organic additive. For example, aromatic solvents such as toluene, xylene, benzene and phthalic acid ester can be used. Solvents, higher alcohols such as hexanol, octanol, decanol and oxyalcohol, and esters such as acetic acid ester and glyceride can be used. Furthermore, in order to volatilize the solvent slowly, it is also possible to use two or more of the above solvents in combination. Further, the content of the solvent is required to be 0.1% by weight or more based on the paste, and the glass frit or the organic metal and the metal particles are used to maintain the fluidity and moldability of the mixture with the glass or metal particles. It is desirable to lower the viscosity of the mixture of the organic additives and the organic additives to some extent. From such a point, it is desirable that the content of the solvent is 0.1% by weight or more and 35% by weight or less based on the paste.

As described above, the composition of the above-mentioned paste is YB _{6 having an} average particle size of 6 μm as a metal component with respect to the above-mentioned paste.
20% by weight of powder and 40% of Y ₂ O ₃ powder having an average particle size of 6 μm.
A glass frit containing 5% by weight of bismuth borosilicate glass having an average particle diameter of 8 μm, 12.5% by weight of terpineol and diethylene glycol dibutyl ether, and 10% by weight of a cellulose resin is used.

An anode 11 is formed on the back plate 5 that has been washed and annealed, in a direction perpendicular to the cathode 12 of the front plate 4. The anode 11 is formed by screen printing using an electrode paste containing Ag as a main component (NFP XFP5392), and then heated to 140 ° C. in a belt drying furnace at 10 ° C.
Hold for a minute and let dry. In this embodiment, two-layer printing was performed to obtain a width of 100 μm and a film thickness of 20 μm. Other conductive materials such as aluminum, nickel, silver, and silver-palladium can be used as other anode materials.
The anode may be formed into a thin film by an evaporation method, a sputtering method, or the like, and then may be formed by a conventional forming method such as patterning by photoetching or sandblasting.

Next, the partition walls 8 are formed on the back plate between the anodes 11 by screen printing using a thick film insulating paste (Okuno Pharmaceutical Co., Ltd. G3-2125) containing low melting glass and a suitable filler. After forming, 14
Hold at 0 ° C. for 10 minutes and dry. In this embodiment, 10-layer printing was performed to obtain a width of 150 μm and a film thickness of 200 μm.
The partition 8 may be formed by a conventional method such as a sand blast method. Next, phosphors corresponding to the respective display colors are applied to the side surfaces of the back plate 5 and the partition walls 8 by screen printing.

Thereafter, the front panel 4 and the rear panel 5 are baked at a predetermined temperature in a range that does not cause thermal deformation, here 585 ° C., thereby forming the partition 8, the anode 11 and the cathode 12. However, the arrangement, film thickness, and dimensions of the anode, the cathode, and the partition wall are not limited to these, and may be the same as conventional discharge cell shapes having various structures. In addition, here, firing is performed all at once after forming the cathode, anode, partition, and phosphor as discharge cell components, but firing may be performed individually each time each discharge cell component is formed.

Thereafter, the cathode 12 on the front panel 4 and the rear panel 5
The front plate 4 and the back plate 5 are overlapped so that the upper anodes 11 face each other, and the periphery is hermetically bonded with a sealing material 9 such as low-melting glass. Further, an ionizable gas is sealed in the discharge space 10 to complete the gas discharge display panel in this embodiment. In this embodiment, Xe is used as an ionizable gas type.
However, helium, neon, argon, xenon, and a mixed gas thereof may be filled.

[0053]

[Table 1]

Table 1 shows panel characteristics using each cathode material in DC discharge.

(1) From Table 1, according to the present invention, a conductive path is secured by mixing a conductive material with an insulating metal oxide having excellent sputter resistance and secondary electron emission efficiency, thereby enabling DC discharge. In particular, the present invention in which a boride compound of a rare earth element is mixed as a conductive material has excellent characteristics such as spatter resistance and high secondary electron emission efficiency as compared with a case where a conductive material such as Ag or Al is mixed. By enabling the DC discharge, the driving voltage can be reduced, the cost of the driving circuit can be reduced, and the spatter energy can be reduced to improve the panel life.

(2) From Table 1, it can be seen from JP-A-7-230770.
Material BaAl in Japanese Patent Application Publication _TwoO_FourCompared with
Since the metal oxide mixed in the light has excellent spatter resistance,
The coated electrode to which the mixed substance according to the present invention is applied is a conventional method.
(Disclosed in JP-A-7-230770).
While decreasing, the spatter resistance improves, and the
When the change over time in the discharge characteristics due to sputtering is suppressed,
In addition, the transmission of the back plate and thin glass by sputter deposits
The rate can be prevented from lowering. Therefore, the panel
The life can be improved.

(3) By generating BaO or Ba from BaA1 ₂ O _{4 by} plasma spraying, the insulating material itself exhibits high secondary electron emission efficiency instead of exhibiting excellent secondary electron emission efficiency. The use of a material having excellent characteristics is effective in lowering the discharge voltage without depending on the deposition process of the coated electrode. In addition, it is possible to apply the screen printing method, which requires no special equipment, and the process is easy, so that the work efficiency and the yield rate can be improved compared to the plasma spraying method, and the capital investment can be greatly reduced. is there. This is particularly noticeable when manufacturing a plasma discharge cell of 40 inches or more. Furthermore, when two or more types of metal particles are applied and formed, the screen printing method is more excellent in dispersibility of the metal particles than the plasma spraying method, so that the metal particles forming the coated electrode are uniformly dispersed and, as a result, stable. A uniform discharge is obtained.

(4) Since the insulating material used in the present invention is a metal oxide, there is no influence of the oxidation due to the atmosphere in the process or the heat process, so that the initial aging is easy.

(5) By setting the particle size of the boron compound of the rare earth element and the metal oxide to 0.5 to 15 μm,
Desirable printability in screen printing, adhesion to a substrate, and resistance change characteristics due to oxidation of a rare earth element boride compound in a firing atmosphere can be obtained. As a result, more stable discharge can be obtained.

(6) In the screen printing method, when the content of the organic metal or glass frit functioning as a binder is in the range of 1 to 30% by weight with respect to the paste, the distance between each particle and between the particle and the back plate is reduced. Has good adhesion, does not decrease the conductivity, and has good characteristics as a cathode, so that a stable discharge can be obtained.

[0061]

As described above, according to the present invention, there is provided a gas discharge display tube having a long life and a gas discharge display tube having a stable and low voltage discharge without adding mercury into a discharge cell, and a plasma display device having a liquid crystal layer. Provision is possible.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view for explaining a plasma addressed display device and a method of manufacturing the same in a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a DC-driven plasma display panel according to a second embodiment of the present invention.

FIG. 3 is a schematic sectional view showing the structure of a conventional plasma addressed display device.

FIG. 4 is a schematic cross-sectional view showing the structure of a conventional DC-driven plasma display panel.

FIG. 5A is a correlation diagram of the particle size of metal particles and printability in a screen printing method.

FIG. 5B is a correlation diagram of the particle size of metal particles and the adhesion to a substrate.

FIG. 5C is a correlation diagram between the particle size of metal particles and a change in resistance due to oxidation of a rare earth element boride compound.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display cell 2 Discharge cell 3 Thin glass 4 Front plate 5 Back plate 6 Liquid crystal layer 7 Signal electrode 8 Partition wall 9 Seal material 10 Discharge space 11 Anode 12 Cathode 13 Bus electrode 14 Cover electrode 15 Spacer 16 Phosphor

Continued on the front page F term (reference) 5C027 AA02 AA03 5C040 FA02 FA04 FA09 GB03 GB06 GB08 GB09 GC03 GC04 GC12 GC18 GC19 JA07 JA12 JA15 KA04 KA05 KA09 KB02 KB04 KB17 MA03 MA10 MA17 MA26

Claims (6)

[Claims] 1. A gas discharge display panel comprising an anode and a cathode which are exposed in a discharge space and opposed to each other with a discharge interval therebetween, and which are sealed together with an ionizable gas in an airtight container. At least one includes a boride compound of a rare earth element and a metal oxide, wherein the boride compound of the rare earth element is at least one of hexaboride and tetraboride of La, Gd, Y, Nd, Ce, and A gas discharge display panel, wherein the metal oxide contains at least one of MgO and Y ₂ O ₃ . 2. The gas discharge display panel according to claim 1, wherein said rare earth element boride compound and said metal oxide have a particle size in the range of 0.5 to 15 μm, respectively. 3. The gas discharge display panel according to claim 1, wherein the gas discharge display panel is a plasma addressed display device having a liquid crystal layer. 4. A method for manufacturing a gas discharge display panel, comprising: an anode and a cathode exposed to a discharge space, opposed to each other with a discharge interval therebetween, and sealed together with an ionizable gas in an airtight container. And a method for manufacturing a gas discharge display panel, wherein at least one of the anodes is formed by a screen printing method using a paste containing a boride compound and a metal oxide. 5. The gas discharge display according to claim 4, wherein the paste contains an organic metal or a glass frit functioning as a binder in a range of 1 to 30% by weight based on the paste. Panel manufacturing method. 6. The method of manufacturing a gas discharge display panel according to claim 4, wherein the gas discharge display panel is a plasma addressed display device having a liquid crystal layer.