JP3029972B2 - Image display device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device such as a plasma display or a fluorescent display tube and a method for manufacturing the same, and more particularly to a structure and a method for manufacturing a rib-like wall provided in an airtight space.

[0002]

2. Description of the Related Art For example, a PDP (Plasma Display Panel) is used as an image display device of a type in which an image of a desired character, symbol, figure, or the like is displayed by selectively emitting light from a part of an airtight space. ) And V
FD (fluorescent display tube: Va cu um Fluorescent Display) and the like are known.

[0003] In the above-mentioned PDP, for example, a rib-like wall for dividing an airtight space formed between a pair of parallel flat plates into a plurality of discharge spaces, and selectively generating a discharge in the plurality of discharge spaces. And a plurality of discharge electrodes for emitting light using plasma generated by discharge in a selected predetermined discharge space. For example, in a single-color display PDP, light emission of neon orange or the like accompanying the generation of plasma is used for display as it is, while in a color display PDP, a phosphor is provided in a discharge space, and ultraviolet light generated by the plasma causes The excited light emission of the phosphor is used for display. Such a PDP is relatively easy to have a thin large display surface, and has a relatively wide viewing angle and a fast response speed comparable to a cathode-ray tube. Therefore, it is considered as an image display device replacing the cathode-ray tube.

The above-mentioned VFD has a plurality of anodes and a phosphor layer fixed on the anode on one surface of a flat plate facing the airtight space, and is located at a position separated from the one surface in the airtight space. In addition, a cathode is provided, and electrons generated from the cathode collide with the phosphor layer to selectively emit light from the phosphor layer. In such a VFD, the operating voltage is low and the display is clear because the surface of the phosphor layer on which electrons generated from the cathode collide is located on the display side, and a phosphor layer having a different emission color is prepared. Therefore, it is often used as a display component of an audio device or a display panel of an automobile because it has a feature of enabling color display.

In the above-described VFD, a grid electrode for controlling light emission of the phosphor layer on the anode is provided for each control unit of the phosphor layer. When a positive voltage is applied to a predetermined grid electrode, electrons generated from the cathode are accelerated by the grid electrode and collide with the phosphor layer on the anode located at a position corresponding to the grid electrode, thereby causing The phosphor layer emits light, but when a negative voltage is applied to a predetermined grid electrode, electrons generated from the cathode are shielded, and the phosphor on the anode at a position corresponding to the grid electrode is shielded. The layer does not emit light.

Various structures are considered for the grid electrode. For example, one used for a VFD described in Japanese Patent Application Laid-Open No. Sho 62-290050 is one example. In this VFD, a rib-like wall is provided around a phosphor layer, and a grid electrode is formed on the top of the rib-like wall.
Light emission is controlled for each phosphor layer located inside the grid electrode. According to this technology, a relatively high luminance can be obtained because the light emission from the phosphor layer is not blocked unlike the conventionally used mesh grid electrode, and the grid electrode is provided at a relatively high position as in the past. Since it is positioned between the cathode and the anode, there is a feature that a sufficient acceleration shielding effect can be obtained.

[0007]

The above-mentioned conventional PDP and VF
D includes a flat plate having one surface facing the airtight space, and a rib-like wall standing on the one surface of the flat plate to partition the one surface. This rib-like wall is formed, for example, by the following method. A screen printing method in which a thick film insulating paste is printed and laminated using a thick film screen having a predetermined pattern. A dry etching method in which a mask having a predetermined pattern is formed on a thick film insulating paste which is entirely printed and laminated by a blade or the like, and unnecessary portions of the thick film insulating paste are removed by glass bead blasting or the like. A lift-off method in which a thick-film insulating paste is filled into recesses between photoresist films formed in a reverse pattern of rib-like walls, and then the photoresist film is removed. A photolithography method in which a thick film insulating paste to which a photosensitive material (photoresist) is added is coated on the entire surface by printing and laminating or coated with a blade to form a pattern.

As the above thick film insulating paste, for example, an inorganic binder such as a low melting point glass, a suitable filler (ie, a filler such as alumina, zirconia, lead titanate, barium titanate, etc., or a sintering temperature) To which glass having a high softening point is added. This filler is added for the following purpose. The rheology of the thick insulating paste is controlled to absorb variations in film forming conditions, drying conditions, firing conditions, and the like. The thick film pattern shrinkage due to the softening of the inorganic binder at the time of baking is suppressed, and the variation in the baking residual ratio (for rib-shaped walls, [volume after baking / volume after printing / drying and before baking]) is reduced. Thereby, a predetermined dimensional accuracy for uniform display in an airtight space (for example, a discharge gap in PDP, an anode-grid gap in VFD)
In addition, the cross-sectional shape accuracy for making the viewing angle uniform can be secured, and display characteristics can be obtained. In the screen printing method, shape retention of a printed pattern is obtained and the number of laminations is reduced. In the dry etching method, the removal efficiency by blasting is increased. In the lift-off method, the paste can be uniformly filled by adjusting the viscosity of the paste or the adhesive strength with the substrate. In the photolithography method, the resolution is controlled.

In the above-mentioned thick film insulating paste, the higher the proportion of the filler added, the higher the firing residual ratio and the higher the material efficiency. This effect is particularly remarkable in the case of the screen printing method, but the manufacturing efficiency is also improved in other manufacturing methods. However, on the other hand, a large number of fine openings are formed in the fired rib-shaped wall in proportion to the addition ratio of the filler, and the surface area thereof becomes large.

In an image display device such as the PDP or VFD, which emits electrons in an airtight space and emits light directly or indirectly, when an impurity gas is present in the airtight space,
In a PDP, the purity of an inert gas for discharge is reduced, and
In FD, the degree of vacuum decreases. In any case, the electrodes and the phosphor are deteriorated, and the light emission / display quality is deteriorated. Therefore, it is necessary to reduce impurity gas in the hermetic space as much as possible. However, if the rib-like wall is formed porous as described above,
Binder components (that is, unburned components) in the thick-film printing paste that have not been decomposed during the firing process are included, and gases such as moisture and carbon dioxide are adsorbed, and unburned after filling with an inert gas or vacuum processing. There is a problem that the gas contained in the components and the adsorbed gas (that is, the impure gas) are gradually released into the hermetic space through the fine openings. Therefore, in the process of forming the hermetic space, it is necessary to remove them by heating, for example, but it is not possible to heat them to a temperature at which degassing can be sufficiently performed due to restrictions on materials and processes.

On the other hand, if the rib-like wall is formed densely, the gas is hardly adsorbed on the rib-like wall, and the gas contained in the unburned components contained therein does not easily flow into the air-tight space. There is no problem that the impurity gas is released into the inside, but in order to form a dense rib-like wall, it is necessary to use a thick-film insulating paste having a relatively low firing residual ratio. For this reason, the number of times of printing and lamination increases, and the manufacturing efficiency is reduced. In addition, the deformation at the time of firing is increased, and high shape accuracy cannot be obtained. Moreover, with a dense ribbed wall,
This causes a problem that processing by dry etching or the like becomes difficult.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to maintain high production efficiency and shape accuracy and to discharge impurity gas into an airtight space. It is an object of the present invention to provide an image display device having a rib-like wall which can be suppressed to a low level and a method of manufacturing the same.

[0013]

A first aspect of the present invention for achieving the object is to provide a flat plate having one surface facing an airtight space and a flat plate standing on one surface of the flat plate. A rib-shaped wall that divides one surface, and a paper
And a layer produced from paste, an image display device of the type for displaying a desired image by causing selectively emitted from a portion surrounded by the rib-like walls of the airtight space, the ribs The wall is a relatively porous body, a relatively dense coating layer provided on the surface of the body ,
Than the coating layer provided on a predetermined part of the surface of the coating layer
And a porous thickness control layer .

[0014]

[Function and Effect of the first invention] In this way, the rib-like wall is relatively Since the porous surface of the body portion of the is covered with a relatively dense coating layer, the airtight space of the image display device Is provided with a rib-like wall having a relatively dense surface layer. Therefore, when the gas is not adsorbed to the surface layer portion, the unburned component in the thick film printing paste is included in the fine opening of the main body portion, or the gas such as moisture or carbon dioxide is adsorbed. In addition, the coating layer prevents the release of the impurity gas into the hermetic space. Moreover, since the main body of the rib-like wall is made porous, a material having a high residual firing rate can be used as in the conventional case. If the surface layer of the rib-shaped wall is dense, impure gas such as gas in unburned components and adsorbed gas contained in the fine opening of the main body may be released into the hermetic space. Because of the suppression, the material constituting the main body is not limited in terms of characteristics. Therefore, it is possible to obtain an image display device having a rib-like wall that can maintain high manufacturing efficiency and shape accuracy and can appropriately suppress the release of impurity gas into the hermetic space. Change
In addition, a predetermined portion of the surface of the coating layer has a more porous thickness.
Because the control layer is provided, the surface of the rib-shaped wall is
When forming any layer using a paste, the thickness control layer
The flow resistance of the paste was increased on the surface of
Control the thickness of the rib-like wall surface
It is possible. For example, ribbed wall surfaces and flat plates
When a phosphor layer is provided on one side, the side wall surface of the rib-like wall
By providing a thickness control layer only on top of
The thickness of the paste can be made substantially uniform.

[0015]

A second aspect of the present invention for achieving the above object is to provide a flat plate having one surface facing an airtight space, and an upright standing on one surface of the flat plate. Manufacturing of an image display device of a type in which a desired image is displayed by selectively emitting light from a part surrounded by the rib-shaped wall in the hermetic space. The method, wherein the rib-like wall is: (a) forming a main body portion having a predetermined height and forming a relatively porous main body portion; and (b) firing the upper end surface of the formed main body portion. (C) scanning a squeegee in a direction parallel to the upper end surface of the main body, and placing the thick film insulating paste on the upper end surface thereof. By scraping off the thick-film insulating paste, the side wall surface of the main body is removed from the thick-film insulating paste. And in the coating step of coating, (d)
And a heating step of heating and generating a relatively dense coating layer from the thick film insulating paste.

[0016]

In this way, the rib-like wall of the image display device forms a relatively porous main body in the main body forming step, and has a predetermined thickness on the upper end surface of the main body in the mounting step. The film paste is placed, and in the coating step, the squeegee is scanned in a direction parallel to the upper end surface of the main body to scrape off the thick insulating paste, thereby covering the side wall surface of the main body with the thick insulating paste, Further, it is formed by heating in a heating step to form a relatively dense coating layer from the thick film insulating paste. In this case, the thick-film insulating paste adjusted to an appropriate viscosity is caused to flow downward along the side wall surface of the main body by scraping off with a squeegee, but the side wall surface is made porous. Since the flow resistance on the surface is high, the flow is caused to flow down while being partially fixed to the side wall surface.

[0017]

As described above, the rib-shaped wall including the relatively porous main body and the relatively dense coating layer shown in the first invention, that is, high shape accuracy and high production efficiency are maintained. In addition, an image display device having a rib-like wall capable of suitably suppressing the release of impurity gas into the hermetic space can be obtained.
In addition, in the above-mentioned main body portion forming step, for example, various methods generally used conventionally, such as the above-described screen printing method and dry etching method, can be used.

Here, in the first and second aspects of the present invention, preferably, the coating layer of the rib-like wall is formed of a low-melting glass that does not contain lead (Pb) and an alkali component (such as Na). Lead and alkali components are generally added to low-melting glass for the purpose of adjusting the melting point and reducing manufacturing costs, and are present as PbO, NaO, or the like. Therefore, there is a possibility that a failure may occur in the structure, electric driving conditions, and reliability of the image display device, so that it is not preferable as an electronic component. According to the above, since such an element is not contained in the coating layer, when an image display device is used, the discharge characteristics and insulation properties are reduced due to the presence of the lead element, and the presence of an alkali component is present. Therefore, it is possible to preferably suppress a decrease in insulation reliability and the like caused by acceleration of the migration.

[0019]

[0020]

An embodiment of the present invention will be described below with reference to the drawings. In the following description, dimensional ratios and the like of each part in the drawings are not necessarily drawn accurately.

FIG. 1 is a diagram showing the structure of a DC PDP 10 which is an embodiment of the image display device of the present invention. The DC PDP 10 is made of, for example, a glass plate, and has a front plate 12 having a light-transmitting property and a back plate 1 made of a glass plate.
4 and a plurality of elongated partition walls 18 forming a plurality of parallel discharge spaces 16 between the front plate 12 and the back plate 14. The interval between the partition walls 18, that is, the width of the discharge space 16 is about 0.3 to 2.0 mm, and the height of the partition wall is about 100 to 500 μm. In this embodiment, the back plate 14 corresponds to a flat plate, the discharge space 16 corresponds to an airtight space, and the partition 18 corresponds to a rib-like wall.

A plurality of trigger electrodes 20 whose longitudinal direction is orthogonal to the partition wall 18 are covered by a dielectric layer 22 on the inner surface of the front plate 12 located on the rear plate 14 side. On the surface of the dielectric layer 22, a plurality of cathode electrodes 24 are provided along the trigger electrode 20 in a slightly shifted state in the width direction. The trigger electrode 20 and the cathode electrode 2
4 are arranged at substantially equal intervals, and are insulated by a dielectric layer 22. This enables an AC discharge (trigger discharge) between the trigger electrode 20 and the cathode electrode 24. Have been.

The trigger electrode 20 is made of, for example, Ag,
The conductive layer such as Au, Al or the like is formed to a thickness of, for example, about 0.5 to 15 μm by thick-film printing, and the dielectric layer 22 is similarly formed of a low-softening point glass or the like by a thick-film printing. Thereby, for example, the thickness on the trigger electrode 20 becomes
It is formed to about 20 to 60 μm. The cathode electrode 24 has, for example, a width of about 0.1 to 0.5 mm and a thickness of about 5 mm.
It is formed by printing a thick film of a conductor such as Ni (nickel) or Al (aluminum) to a size of about 50 μm, and is formed between a plurality of cathode electrodes 24, that is, the center of adjacent cathode electrodes 24. The distance is, for example, 0.3-2.
It is about 0mm.

On the back plate 14, a plurality of anode electrodes 26 are arranged at equal intervals along the plurality of partitions 18 at positions therebetween. That is, the cathode electrode 24 and the anode electrode 26 are arranged in a matrix at right angles to each other, and the intersection of the cathode electrode 24 and the anode electrode 26 is one of the PDPs 10.
Equivalent to a dot. The anode electrode 26 has, for example, a width
Dimensions of about 0.1 to 0.5 mm, thickness of about 0.05 to 0.5 μm,
Like the cathode electrode 24, it is formed by printing a thick film of Ni, Al, or the like, and the interval between the plurality of anode electrodes 26 is, for example, about 0.3 to 2.0 mm.

The partition wall 18 is made of glass having a low softening point. As shown in an enlarged cross section in FIG. 2, the partition wall 18 has a large number of fine openings having a porosity of about 15 to 70%. It comprises a porous main body 28 and a relatively dense coating layer 30 covering the main body 28, for example, having a thickness of about 2 to 10 μm and a porosity of about 0 to 30%.

The main body 28 is made of, for example,
A certain amount (for example, about 50 wt%) of a filler such as alumina and an organic component (resin and solvent) for obtaining viscosity are added to lead glass generally used as a material for Formed from the adjusted glass paste. The main body 28 is formed by repeating printing and drying by thick film screen printing using a predetermined plate, laminating the above-mentioned glass paste on the back plate 14 to a predetermined height, and firing at a predetermined temperature. You. The above-mentioned filler obtains shape accuracy by reducing the viscosity of the glass paste, ensuring the shape retention of the thick film printing pattern, and increasing the firing residual ratio of the main body 28, and also reduces the number of times of printing and laminating to increase the manufacturing efficiency. Therefore, the main body 28 has a porosity of 15 to
It is about 70% porous. In the present embodiment, the printing and laminating step and the baking step correspond to a main body part forming step.

On the other hand, the coating layer 30 is formed, for example, as follows. First, for example, Japanese Patent Application Laid-Open No. 3-196441
(Eg, page 13, upper left column, thirteenth
(See line 12 to line 12 in the lower left column of the same page.) As shown in FIG. 3A, the upper end face 32 of the main body 28 is formed by using a method of manufacturing a spacer (rib-like wall) having a high aspect ratio. A low-melting glass paste 34 that becomes relatively dense after firing is
Place with a thickness of about 5 to 20 μm. According to the technique described in the above publication, a spacer pattern wider than the width of the spacer base or a solid printing surface is provided on a spacer base formed in advance (corresponding to the main body 30 in this embodiment). The paste is printed using a plate.
When the plate is brought into contact with the upper end surface of the spacer base as the squeegee moves, the paste is applied only to the upper end surface in contact with the spacer due to the characteristics of screen printing.

The low melting point glass paste 34 is
For example, it does not contain lead (Pb) or alkali (Na, etc.)
The _{Bi 2 O 3 -ZnO -B 2 O} 3 -SiO 2 based glass or the like, which organic component for obtaining a viscosity (resin and solvent) is added,
A material to which a large amount of filler such as the above-described main body 28 is not added is used. The addition of the filler is the minimum amount necessary mainly for coloring and adjusting the viscosity. The thickness of the low-melting glass paste 34 placed above is appropriately set according to the dimensions of the main body 28 and the thickness of the coating layer 30 to be formed. In this embodiment,
The step of placing the low-melting glass paste 34 on the upper end face 32 shown in FIG. 3A corresponds to the placing step.

Then, as shown in FIG. 3B, the squeegee 36 is moved in a direction (horizontal direction) perpendicular to the arrow direction in the figure, that is, perpendicular to the longitudinal direction of the main body 28 and parallel to the upper end surface 32 thereof.
Move to At this time, the tip of the squeegee 36 is kept at a predetermined slight distance d from the upper end face 32 due to its elasticity, the viscosity of the low-melting glass paste 34, and the like.
Thereby, the low melting point glass paste 34 is applied to the main body 28.
Is scraped off from the upper end surface 32 of the
The squeegee 36 flows down along the side wall surface 38 of the main body 28 in accordance with the gravity and the viscosity of the squeegee 36 in the traveling direction of the squeegee 36.
Cover. Further, by moving the squeegee 36 in the direction opposite to the direction shown in FIG. 3 (b), the low melting point glass paste 34 is scraped off on the opposite side wall surface 38, and the entire side wall surface 38 of the main body 28 is removed. It is covered with the low melting point glass paste 34. The squeegee 3 in the opposite direction as described above
Prior to the movement of 6, the low-melting glass paste 34 is placed on the upper end face 32 again by the above-described method as necessary.

Thereafter, the coating layer 30 is formed from the low-melting glass paste 34 by firing at a predetermined temperature. In the present embodiment, the step shown in FIG. 3B corresponds to the coating step, and the step of firing at a predetermined temperature corresponds to the heating step.

The DC PDP 46 is formed by printing and firing the trigger electrode 20, the cathode electrode 24 and the like on the front plate 12 and the anode electrode 26 and the partition 18 on the back plate 14 as described above. It is manufactured by joining the front plate 12 and the back plate 14 at a peripheral portion (not shown), and a discharge gas such as He, Ne, Xe or the like is sealed in the discharge space 16 at a pressure of 200 to 500 torr. You.

The DC PDP 46 constructed as described above
Is driven as follows. First, by applying a relatively high negative voltage to all the trigger electrodes 20 and a predetermined positive voltage to all the anode electrodes 26 simultaneously for a short time, an auxiliary discharge (so-called trigger setting) between the trigger electrodes 20 and the anode electrodes 26 is performed. ) Occurs, and charges are accumulated on the surface of the dielectric layer 22 covering the trigger electrode 20. Then, once the application of the voltage to both electrodes 20 and 26 is stopped, a predetermined negative voltage is sequentially applied to cathode electrode 24 to perform scanning, and a predetermined anode voltage is applied to predetermined anode electrode 26 in synchronization with the scanning. When a positive voltage is applied, a main discharge is generated between the cathode electrode 24 and the anode electrode 26 to which the voltages are applied, and light emission is sequentially generated at the intersection between the two, and a desired character, graphic, symbol, or the like is generated. The image is displayed. In this case, by applying a negative voltage to the cathode electrode 24, a trigger discharge is generated between the cathode electrode 24 and the trigger electrode 20 via the dielectric layer 22, whereby the cathode electrode 24 and the anode electrode 26
And the main discharge voltage between them is reduced.

Here, in the present embodiment, the partition 18
Is composed of a relatively porous main body 28 and a relatively dense coating layer 30 covering the surface of the main body 28 (that is, the upper end surface 32 and the side wall surface 38). In the discharge space 16, a partition 18 having a relatively dense surface layer is provided. Therefore, no gas is adsorbed on the surface layer, and the main body 2
Even when the unburned components of the resin in the glass paste are included in the fine openings of No. 8 or a gas such as moisture or carbon dioxide is adsorbed, the impure gas is discharged into the discharge space 16 after the discharge gas is filled. Is prevented by the coating layer 30.

In addition, since the main body 28 of the partition 18 is relatively porous, a material having a high residual firing rate can be used as in the prior art. As long as the surface layer portion of the partition wall 18 is dense, an impurity gas such as a gas in an unburned component or an adsorbed gas contained in a fine opening of the main body portion 28 is discharged into the discharge space 16. Therefore, the material constituting the main body 28 is not limited in terms of characteristics. Therefore, the DC PDP 10 having the partition walls 18 that can maintain high manufacturing efficiency and shape accuracy and can appropriately suppress the release of the impurity gas into the discharge space 16 can be obtained. Although unburned components such as resin may remain in the coating layer, the resin is easily burned because the film thickness is as thin as about 2 to 10 μm as described above, and the unburned components become extremely small. There is no particular problem.

Further, according to the present embodiment, after the main body 28 is formed by printing and laminating a low melting point glass paste having a relatively high firing residual ratio, the main body 28 is formed on the upper end face 32 of the main body 28 after firing. The low-melting glass paste 34 which becomes dense is placed, and the squeegee 36 is scanned in a direction parallel to the upper end surface 32 to scrape the low-melting glass paste 34 and sinter it. The end surface 32 and the side wall surface 38 are covered with the relatively dense covering layer 30. In this case, the low-melting glass paste 34 adjusted to have an appropriate viscosity is caused to flow downward along the side wall surface 38 of the main body 28 by being scraped off with a squeegee 36. Since it is porous and has high flow resistance on its surface, it flows down while being partially fixed to the side wall surface 38. Therefore, the partition wall 18 is provided which can appropriately suppress the discharge of the impurity gas into the discharge space 16 without lowering the shape accuracy and lowering the manufacturing efficiency due to the use of the low melting point glass having a low residual firing rate. As a result, a DC type PDP 10 is obtained.

The low-melting glass forming the coating layer 30 does not contain lead and alkali components.
A decrease in discharge characteristics and insulation due to the presence of lead on the surface of the partition wall 18 and a decrease in insulation reliability resulting from acceleration of migration due to the presence of an alkali component are suitably suppressed.

Further, the coating layer 30 is provided on the surface of the side wall surface 38 by scraping off the low melting point glass paste 34 placed on the upper end surface 32 with a squeegee 36. The generation of pinholes on the surface of the coating layer 30, which is a problem when screen printing is performed directly on the side wall surface 38, is suitably suppressed,
Release of the impurity gas into the discharge space 16 is more reliably prevented.

Next, another embodiment of the present invention will be described. In the following embodiments, portions common to the above-described embodiments will be denoted by the same reference numerals and description thereof will be omitted.

FIG. 4 is a diagram showing the structure of the DC type color PDP 40. The DC type color PDP 40 includes a grid-like partition wall 42 that forms the discharge spaces 16 arranged in a matrix between the front plate 12 and the back plate 14. In this embodiment, the discharge space 16 is 1
Make up the dots. That is, the "selectively emit light" portion in the claims is a discharge space (airtight space) 16 surrounded by a partition (rib-like wall) 18 as in the above-described embodiment.
The discharge space 16 surrounded by the lattice-shaped partition walls 42 is provided in the hermetic space as in the present embodiment, and the discharge space 16 is provided in units of the discharge space 16 (that is, a part of the hermetic space). It may be.

On the inner surface of the back plate 14 on the front plate 12 side, a trigger electrode 44 of, for example, about 1 to 10 μm in thickness covering the entire surface thereof, and a dielectric of, for example, about 30 to 60 μm in thickness covering the entire surface of the trigger electrode 44. A layer 46 is provided. In the present embodiment, the anode electrode 26 and the grid-like partition 42 are provided on the back plate 14 via the trigger electrode 44 and the dielectric layer 46. In this embodiment, the dielectric layer 46 is provided on the back plate 14 side.
And the trigger electrode 44, the anode electrode 26 is provided on the inner surface of the front plate 12 on the back plate 14 side.
Only cathode electrodes 24 arranged in a direction perpendicular to the direction are provided.

The dielectric layer 46 and the anode 2
A phosphor layer 48 having a thickness of, for example, about 10 to 60 μm is provided on the upper surface of the substrate 6 and the side wall surface of the lattice-shaped partition wall 42.
The phosphor layer 48 is made to emit light by ultraviolet light, ie, excitation light, generated by a discharge between the cathode electrode 24 and the anode electrode 26, and R (red), G
Phosphors corresponding to emission colors such as (green) and B (blue) are provided for each discharge space 16. Note that the phosphor layer 48 is
It is not provided in the rectangular portion 49 at the bottom center in each discharge space 16 (that is, immediately below the cathode electrode 24), and the anode electrode 26 is partially exposed.

As shown in cross section in FIG. 5, the grid-like partition 42 has the same main body 28 and the coating layer 3 as the partition 18 described above.
However, a second coating layer 50 that further covers the upper portion of the coating layer 30 is provided in a portion above the intermediate portion in the height direction. This second coating layer 50
Is formed to be more porous than the above-mentioned coating layer 30, whereby the side wall surface of the lattice-shaped partition wall 42 is relatively porous on the upper side and relatively dense on the lower side.

The second coating layer 50 is formed by the method shown in FIG. 3 of the above-described embodiment, but has a relatively high paste viscosity and a relatively small amount to be placed on the upper end surface 32. Has been reduced. Therefore, as shown in FIG. 3 (b), when scraped off by the squeegee 36, it does not reach the lowermost part, that is, the surface of the dielectric layer 46 formed on the inner surface of the back plate 14, and the height of the coating layer 30 is not increased. It is formed at a position from the upper end surface to the middle part in the height direction, while being stopped by the flow to the middle part in the height direction.

The phosphor layer 48 is formed by using a phosphor paste prepared by mixing a resin material, a solvent, or the like with a phosphor material corresponding to an emission color such as R, G, B, etc. It is formed in the same manner as in the above. The phosphor layer 4
In forming the anode electrode 8, a portion of the anode electrode 26 exposed by the rectangular portion 49 is provided with a layer repelling a phosphor paste (for example, a hydrophilic film when the phosphor paste is oily, and a hydrophilic film when the phosphor paste is aqueous). The above-described rectangular portion 49 is formed by providing an oleophilic film.
However, instead of forming a rectangular portion 49 by providing a layer that repels the phosphor paste, a convex portion is provided on the anode electrode 26 so that only the convex portion is exposed when the phosphor paste flows. No problem. This phosphor paste generally has a relatively low viscosity, but when flowing on the surface of the second coating layer 50, the second coating layer 50 is formed to be relatively porous and the flow resistance is increased. Therefore, the thickness fixed on the surface is increased. For this reason, despite the fact that the phosphor paste has a relatively low viscosity and a high fluidity, the thickness of the relatively upper portion of the side wall surface of the lattice-shaped partition wall 42 is relatively large, and the phosphor paste has a relatively high viscosity. The thickness of the entire body layer 48 is substantially uniform.

That is, in the prior art, the phosphor layer 48 is
Are provided only on the inner surface of the back plate 14 or the surface of the dielectric layer 46.
In (2), it is known that the luminance depends on the amount of the phosphor provided in the discharge space 16, and a substantially proportional relationship can be obtained in a normal range of the thickness of the phosphor layer 48 (for example, 40 μm or less). ing. Therefore, it is desirable that the phosphor layer 48 be provided not only on the inner surface of the back plate 14 or the surface of the dielectric layer 46 but also on the side wall surface of the partition wall 42. It is difficult to print the phosphor paste on such a side wall surface by screen printing, and a method of scraping the phosphor paste from the upper end surface 32 of the partition wall 42 in the same manner as the coating layer 30 (the method shown in FIG. 3). Can be considered. However, since the phosphor paste has a relatively low viscosity, if the flow resistance on the side wall surface of the partition wall 42 is made uniform, the amount of the phosphor paste remaining on the side wall surface is relatively small, and the phosphor flowing down to the lowermost portion is formed. The amount of paste is relatively large,
The thickness is thinner toward the upper side of the partition 42 and thicker toward the lower side. Therefore, the phosphor on the side wall surface does not contribute to the improvement of the luminance, and as a result, high luminance cannot be obtained.

On the other hand, according to the present embodiment, the relatively porous second coating layer 5 is formed only on the upper side of the surface of the coating layer 30.
Since 0 is provided to increase the flow resistance of the phosphor paste, the thickness of the phosphor layer 48 is made substantially uniform as described above, and a sufficient thickness is secured also on the upper side. Therefore, the color PDP 40 having relatively high luminance can be obtained. As is clear from the above description, in the present embodiment, the second coating layer 50 corresponds to a thickness control layer.

FIG. 6 is a diagram showing still another embodiment.
In this embodiment, the viscosity of the low-melting glass paste used for the coating layer 30 is made relatively low, and the amount of the low-melting glass paste placed on the upper end surface 32 of the main body 28 is made relatively large. Ag (silver) provided on the inner surface etc.
The electrode (for example, the address electrode) 52 is covered with the low-melting glass. This low melting glass is N
A material that does not contain an alkali component such as a is used, whereby the migration of the Ag electrode is suitably suppressed. Further, since the coating layer of the Ag electrode 52 is formed thin and without pinholes, it is possible to obtain a suitable address signal condition.

In the embodiment shown in FIG. 7, an electrode 54 is provided at an intermediate portion of the partition wall 18 in the height direction.
The electrodes 54 are formed by printing and laminating a glass paste to a predetermined height in the process of forming the main body 28, and then printing and laminating to a predetermined thickness using an electrode conductive material paste instead of the glass paste. Further, it is formed by printing and laminating a glass paste thereon. The upper end surface 32 and the side wall surface 3 of the main body 28
8 has a coating layer 30 similar to the embodiment shown in FIGS.
Are provided, whereby the electrode 54 is covered with a dielectric material. In the AC type PDP, it is necessary that the discharge electrode is covered with a dielectric material. In this case, the partition electrode 18 is formed, and at the same time, the sustain electrode or the address electrode in the AC type PDP, and the DC type. An auxiliary electrode such as a trigger electrode in the PDP is formed.

FIGS. 8 and 9 are a sectional view and a perspective view showing a VFD 58 according to another embodiment of the present invention. VF
D58 is an airtight space 65 formed by joining a pair of glass substrates 60, 62 at a peripheral portion thereof with a predetermined interval via a frame-shaped spacer glass 64.
It is provided with. One glass substrate 60 has an anode wiring 66 and a grid wiring 6 which are sequentially formed on the inner surface thereof.
7, an insulating layer 68, an anode electrode 70 made of a conductive material such as graphite, and a phosphor layer 72 having a predetermined display pattern (three “8” patterns in FIG. 9) on the anode electrode 70. A rib-like wall 76 is provided upright from the insulating layer 68 toward the other glass substrate 62 at the peripheral edge of the phosphor layer 72, and a grid electrode 74 is provided on the upper end surface thereof. The cathode wiring 78 formed on the inner surface of the glass substrate 60 is provided between the upper end surface of the rib-like wall 76 and the inner surface of the other glass substrate 62.
Are connected to each other.

In the VFD 58, a predetermined voltage is applied between the anode electrode 70 and the cathode electrode 80 via the lead pin 82 and the wirings 66 and 78, and a predetermined control voltage is applied to the grid electrode 74. As a result, electrons generated from the cathode electrode 80 are caused to collide with the phosphor layer 72 to cause the phosphor layer 72 to emit light. 8 and 9, reference numeral 84 denotes a mercury getter, and in FIG. 9, reference numeral 86 denotes an exhaust pipe for evacuating the airtight space 65.

FIG. 10 is an enlarged view showing a cross section of the rib-like wall 76. As shown in FIG. The rib-like wall 76 is composed of a relatively porous main body 88 and a relatively dense covering layer 90 covering the main body 88, and the grid electrode 74 is provided on the covering layer 90. ing. This rib-like wall 76
Is also formed in the same manner as the above-mentioned partition wall 18, and the surface layer portion is made relatively dense. As is clear from FIG. 8, the rib-shaped wall 76 does not partition the airtight space 65, but in the VFD 58, the phosphor layer 72 surrounded by the rib-shaped wall 76 is formed.
Is selectively emitted for each enclosed unit. In other words, if the "rib-shaped wall" in the claims is "one that stands on one surface of a flat plate and separates one surface,"
The airtight space need not necessarily be divided as in the embodiment shown in FIGS. 1 to 7.

In the VFD 58 as described above, a relatively porous material is conventionally used for the rib-shaped wall 76 in order to increase the shape accuracy and the manufacturing efficiency. Therefore, when the impurity gas such as the gas adsorbed on the rib-shaped wall 76 or the gas contained in the unburned components is released into the hermetic space 65 after the vacuum processing, the degree of vacuum is reduced. Therefore, it is not preferable.
According to the present embodiment, as in the case of the DC-type PDP 10 and the like, the rib-shaped wall 76 that can maintain shape accuracy and manufacturing efficiency and can appropriately suppress a decrease in the degree of vacuum due to gas release is provided. VFD 58 is obtained.

While the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be embodied in still another embodiment.

For example, in the above-described embodiment, the case where the present invention is applied to a DC type PDP 10, a VFD 58 or the like has been described. However, the present invention is not limited to these, and a type having a rib-like wall in an airtight space is provided. Then, it can be applied to various image display devices. For example, the shapes of the partition wall 18 and the rib-like wall 76 and the like are appropriately changed according to the shape of the discharge space 16 and the anode electrode 70 and the like, or when applied to the DC PDP 10 and the like, the trigger electrodes 20 and 44 and the like are used. May not necessarily be provided.

Further, in the embodiment, in order to form the coating layer 30 and the like, a low-melting glass (Bi ₂ O ₃ —ZnO—B ₂ O ₃ —SiO ₂ glass or the like) containing no lead and no alkali component is used. Although used, the material composition of the coating layer 30 is not particularly limited as long as it is formed densely. However, in the DC-type PDP 10 and the like shown in the examples, it is desirable that lead is not contained in order to obtain stable discharge characteristics and insulating properties, and that the insulation reliability is hardly reduced due to accelerated migration. Therefore, it is desirable that no alkali component is contained.

The material for forming the main bodies 28 and 88 is not particularly limited in terms of characteristics as long as it is a porous material, and various insulating materials can be used. However, when a low-melting glass paste or the like is used, it is preferable that the shape retention of the printed pattern is higher, and that the higher the firing residual ratio is, in order to increase the shape accuracy and reduce the number of times of printing and lamination, etc. For this reason, it is preferable that a relatively large amount of filler such as alumina is contained (for example, about 50% as shown in the embodiment).

Further, in the embodiment, the main bodies 28, 8
Although 8 is formed by printing and laminating a thick film insulating paste, the main body 28 and the like can be formed by various methods.
For example, an insulating layer having a thickness equal to the height of the main body 28 or the like may be formed on the entire surface of the back plate 14 or the like, and may be formed by a dry etching method such as glass bead blasting. After filling the concave portions between the photoresist films formed in the reverse pattern of the main body portion 28 and the like with the thick film insulating paste, a lift-off method of removing the photoresist film is applied. And a photolithography method or the like for forming a pattern.

In the above-described embodiment, the squeegee 36 was moved in the horizontal direction perpendicular to the longitudinal direction of the main body 28 and parallel to the upper end surface 32 in the covering step shown in FIG. When the thickness of the coating layer 30 is relatively thin (for example, about 10 μm or less), when the thickness variation of the coating layer 30 may be relatively large (for example, about 5 μm or more), If there is no problem in quality even if the low melting glass paste 34 flows into the squeegee 36, the squeegee 36 may be moved in a direction perpendicular to the above-mentioned direction, that is, in a direction parallel to the longitudinal direction of the main body 28.

Although not specifically exemplified, the present invention can be variously modified without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a DC PDP according to one embodiment of the present invention.

FIG. 2 is a diagram illustrating a cross-sectional structure of a partition wall of the PDP of FIG.

3A and 3B are views for explaining a method of manufacturing the partition wall of FIG. 2, wherein FIG. 3A shows a state in which a paste is placed on an upper end surface of a main body, and FIG. 3B shows a state in which a squeegee is scanned. Show.

FIG. 4 is a perspective view showing a structure of a color PDP according to another embodiment of the present invention.

FIG. 5 is a view showing a cross section of a partition wall of the color PDP of FIG. 4;

FIG. 6 is a view showing a cross section of a partition wall according to still another embodiment of the present invention.

FIG. 7 is a view for explaining a sectional structure of a partition used in an AC type PDP according to still another embodiment of the present invention.

FIG. 8 is a view showing a cross-sectional structure of a VFD according to still another embodiment of the present invention.

FIG. 9 is a perspective view showing the entire VFD of FIG. 8;

FIG. 10 is an enlarged view showing the vicinity of a rib-shaped wall of the VFD of FIG. 8;

[Explanation of symbols]

 10: DC type PDP (image display device) {12: front plate, 14: rear plate} (a pair of parallel flat plates) 18: partition wall (rib-like wall) 28: main body portion 30: coating layer

────────────────────────────────────────────────── ─── The continuation of the front page (72) Susumu Sakamoto, inventor, Kyushu Noritake Co., Ltd., 2160, Yatsunami, Yasumachi, Asakura-gun, Fukuoka Prefecture JP, A 62-200633 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 17/04 H01J 9/02 H01J 9/24 H01J 29/86 H01J 31/15

Claims (2)

(57) [Claims] A flat plate having one surface facing an airtight space; a rib-like wall standing on the one surface of the flat plate to partition the one surface ;
An image display device in which a layer formed from a paste is provided on the surface of a rib-like wall, and a desired image is displayed by selectively emitting light from a part surrounded by the rib-like wall in the hermetic space. Wherein the rib-like wall has a relatively porous main body, a relatively dense coating layer provided on the surface of the main body ,
It is more porous than the coating layer provided on a predetermined portion of the surface.
An image display device comprising: a thickness control layer . 2. A flat plate having one surface facing the airtight space, and a rib-like wall erected on one surface of the flat plate and dividing the one surface, and surrounded by the rib-like wall in the airtight space. A method of manufacturing an image display device in which a desired image is displayed by selectively emitting light from a part, wherein the rib-shaped wall forms a relatively porous main body having a predetermined height. A step of forming a thick film insulating paste which becomes relatively dense after firing on the upper end face of the formed main body section at a predetermined thickness; and a direction parallel to the upper end face of the main body section. Scan the squeegee,
A step of coating the side wall surface of the main body with the thick film insulating paste by scraping off the thick film insulating paste placed on the upper end surface; and forming a relatively dense coating layer from the thick film insulating paste. And a heating step of generating heat by heating.