JP2000190188A - Manufacture of plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of obtaining a high quality plasma display panel by quickly and certainly forming a bulkhead with a top surface having a specified height and precise flatness. SOLUTION: Grooves 14 of specified pattern are formed by a resist 12 on a back face board 2 opposing to a front face board, and in the grooves 14 a bulkhead material is deposited by means of plasma spraying method so that a sprayed coating 18 is formed. When a bulged part of this sprayed coating 18 up from the surface of the resist 12 is to be polished, a pressure generated in the internal space 28 is applied to a polish sheet 22 through a resilient sheet 24 so that the polish sheet 22 is swollen out from an opening 21 and the polishing is conducted by automatically moving a polishing tool 19 in the horizontal direction while it is pressed to the surface to be processed and a relative movement is generated between them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a plasma display panel used for a display device or the like, and more particularly to a method of manufacturing a plasma display panel characterized by a step of forming rib-shaped partitions on a back substrate. It is.

[0002]

2. Description of the Related Art In recent years, a plasma display panel, which has attracted attention as a display device suitable for a thin type, includes:
There is a configuration as shown in FIG. This plasma display panel includes a front substrate 1 and a rear substrate 2 which are arranged to face each other. On the front substrate 1, a display electrode 3, a dielectric layer 4, and an MgO dielectric protection layer 7 are formed. I have. On the back substrate 2, an address electrode 8 and a partition base layer 9 cover, and a rib-shaped partition 10 is formed thereon. A phosphor layer 11 is applied between the partitions 10. A discharge gas of 50 is provided between the front substrate 1 and the rear substrate 2.
It is sealed at a pressure of 0 Torr to 600 Torr.
The discharge gas is discharged between the two display electrodes 3 to generate ultraviolet rays, and the ultraviolet rays are applied to the phosphor layer 11 to enable color display. Partition wall 10
Is a partition for forming a discharge cell by forming a minute discharge space for each color of each pixel, and the discharge can be controlled for each cell by the partition walls 10 that insulate the discharge space. In this way, erroneous discharge and erroneous display can be prevented.

Conventionally, when forming the partition 10, means such as a printing method, a sand blast method, a photo paste method or a photo-embedding method have been generally adopted.
All of them have various problems such as requiring a sintering step and increasing the production cost.

Therefore, the present applicant has already proposed a method of manufacturing a plasma display panel which can form a partition by forming the partition by utilizing a plasma spraying method, thereby solving the problems of the conventional partition forming methods. (Japanese Patent Application No. 9-283331). In this method of manufacturing a plasma display panel, the barrier ribs 10 are formed through the steps shown in FIG. 6, and will be briefly described below.

First, as shown in FIG. 1A, after an address electrode 8 is formed on a rear substrate 2 made of a glass substrate, a partition base layer 9 is formed using dielectric glass. Next, as shown in (b), a photosensitive resist 12 is formed on the partition base layer 9 using a photosensitive film. Subsequently, as shown in (c), the photosensitive resist 12 is exposed to ultraviolet light L using a photomask 13 having a predetermined pattern width and a predetermined pitch, and then exposed as shown in (d). Then, development is performed to form grooves 14 having a predetermined pattern in the photosensitive resist 12.

After forming the pattern by the groove 14,
As shown in (e), by performing plasma spraying using a plasma spraying torch 17, a partition wall material is deposited inside the groove 14, and the sprayed coating 18 is raised in a state of being raised from the pattern opening of the photosensitive resist 12. Form. At this time, the plasma spray torch 17 is transported in a horizontal direction at a predetermined pitch in parallel with the photosensitive resist 12, and sprays the entire surface. Next, as shown in (f), the surface of the back substrate 2 of the thermal sprayed coating 18 is polished by polishing after plasma spraying to remove a portion of the thermal sprayed coating 18 raised on the surface of the photosensitive resist 12 and flatten it. That is, the height from the surface of the partition base layer 9 is made uniform and the polished surface roughness is reduced. Finally, as shown in (g), when the photosensitive resist 12 is stripped using a stripping solution, a partition 10 having a predetermined pattern composed of the remaining thermal spray coating 18 is obtained. In this method of manufacturing a plasma display panel,
Since the partition walls 10 are formed by using the plasma spraying method, the conventional baking process is not required, and electric energy consumed in the baking furnace is not required, so that the manufacturing cost can be significantly reduced.

[0007]

However, (f)
In the polishing step of shaving and flattening the portion of the thermal spray coating 18 raised from the surface of the photosensitive resist 12 in the sprayed coating 18 shown in FIG. 1, an operator manually grips a polishing tool such as sandpaper directly or through a jig. It is extremely inefficient because it is polished by work. Moreover, since the polishing is performed manually, it is difficult for even a skilled worker to press the entire polishing tool with a uniform pressure. It is hard to obtain.
Further, since the rear substrate 2 made of a glass substrate generally has some undulations (for example, about 30 μm for a 42-inch glass substrate), each of the thermal spray coatings 18 is polished by hand.
It is extremely difficult to make the heights of the partition walls from the base layer 9 to be a predetermined value, and it is impossible to form the partition walls 10 for maintaining a stable discharge space of plasma.

The present invention has been made in view of the above-mentioned conventional problems, and provides a high-quality plasma display by quickly and reliably forming a partition having a predetermined height and a top surface which is flattened with high precision. It is an object of the present invention to provide a manufacturing method capable of obtaining a panel.

[0009]

In order to achieve the above object, the present invention provides a plasma display panel having a discharge space partitioned by a partition between a front substrate and a rear substrate which are arranged opposite to each other. In the manufacturing method, a pattern forming step of forming a groove of a predetermined pattern with a resist on the back substrate, and a film forming step of depositing a partition material by plasma spraying in the groove to form a sprayed coating for forming the partition A polishing step of flattening the top surface of the thermal spray coating to a certain height by polishing a portion of the thermal spray coating raised from the surface of the resist, and removing the resist to remove the resist from the thermal spray coating. A resist removing step of obtaining the partition wall, wherein the pressure generated in the internal space is applied to the polishing sheet via an elastic sheet in the polishing step. Then, using a polishing tool in which the polishing sheet is expanded outward from the opening, the polishing tool is automatically moved in the horizontal direction by pressing the polishing tool while giving relative motion to the surface to be processed of the thermal sprayed coating and the resist. Thus, the thermal spray coating is polished.

In this method of manufacturing a plasma display panel, a polishing tool having a poor elasticity is swelled from an opening by applying pressure through an elastic sheet,
Since the thermal spray coating is polished while pressing the polishing sheet of the polishing tool against the surface to be processed, the portion swelling from the opening in the polishing sheet is deformed into a planar shape by receiving uniform pressure on the whole. In addition, the entire polishing sheet can be pressed against the surface to be processed with a uniform pressing force, and the top surface of the sprayed coating can be polished to an accurate flat surface. In addition, when the thermal spray coating is polished until it is flush with the resist, the contact area of the polishing sheet suddenly increases and the processing rate drops sharply, so that the resist surface is hardly scraped off. Therefore, the top surface of the thermal spray coating can be polished so as to be exactly flush with the resist while following the undulation of the rear substrate itself, and the thermal spray coating can be made to have a precise and constant height.

[0011] Therefore, it is possible to obtain a partition wall having a constant height and an accurate flat surface and capable of maintaining a stable discharge space of plasma, thereby producing a high quality plasma display panel. Can be. Furthermore, since the polishing of the thermal spray coating is performed while the polishing tool is automatically moved in the horizontal direction, the polishing can be performed much more efficiently than when the operator manually performs the polishing.

[0012] In the above invention, the polishing sheet containing a large number of abrasive grains having a hardness higher than that of the thermal spray coating is held.
It is preferable to perform a linear movement in the horizontal direction while pressing the workpiece surface while applying a rotational motion.

[0013] This allows the abrasive sheet to efficiently polish the thermal spray coating by means of abrasive grains having high hardness, and automatically polishes the thermal spray coating by rotating the polishing sheet linearly in the horizontal direction while rotating. Processing can be performed more efficiently.

Further, in the above-mentioned invention, the polishing sheet moves linearly reciprocally between both ends of the work surface,
It is preferable to move the polishing sheet transversely in a direction perpendicular to the moving direction by a scanning pitch equal to or less than の of the width of the contact area with the surface to be processed of the polishing sheet every time it is moved to the end.

[0015] As a result, it is possible to prevent the occurrence of wavy polishing unevenness on the polished surface of the thermal sprayed coating, so that it is possible to obtain a partition capable of maintaining the plasma discharge space more stably, and to obtain high quality. A plasma display panel can be manufactured.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG.
Is an exploded longitudinal sectional view showing a polishing tool 19 used in a polishing step of the thermal spray coating 18 in the method of manufacturing a plasma display according to one embodiment of the present invention, and FIG. FIG. 2 is a longitudinal sectional view showing a polishing tool 19. FIG. 2 corresponds to the step of FIG. 6F, but the illustration of the address electrode 8 and the partition underlayer 9 is omitted for the sake of convenience, and the same applies to FIGS. 3 and 4 below. In these figures, as shown in FIG. 1, the polishing tool 19 is composed of a holding member 20 having an opening 21 on the bottom surface of a cylindrical container, a polishing sheet 22 mixed and held with abrasive grains 23, rubber and the like. An elastic sheet 24 and a cap member 27 having a blow hole 29 communicating with the internal space 28 are provided.

As shown in FIG. 2, the polishing sheet 22 and the elastic sheet 24 are respectively placed in annular holding grooves 30 formed on the inner peripheral surface near the opening 21 of the holding member 20 in a state of being superimposed on each other. After the peripheral portion of the cap member 27 is engaged, the male screw portion 31 on the outer peripheral surface of the cap member 27 is
Is screwed into the female screw portion 32 on the inner peripheral surface of the cap member 27 so as to be pinched and fixed between the ring-shaped bottom surface 33 of the holding member 20 and the ring-shaped serrated surface 34 at the lower end of the cap member 27. 27 is hermetically sealed. The polishing sheet 22 is formed by adding diamond,
Abrasive grains with high hardness such as carborundum or alumina 2
3 are solidified in a sheet shape by mixing a large number of them.

FIG. 3 is a side view showing a state in which the thermal spray coating 18 is being polished by using the polishing tool 19. The polishing tool 19 has the cap member 27 connected to the rod 38 of the air cylinder 37 and attached in a suspended state, and the internal space of the holding member 20 is supplied through a ventilation hole 29 and a ventilation tube 36 to supply compressed air such as a compressor. It is in communication with a source (not shown). The polishing tool 19
Is a motor 40 fixed to the upper part of the air cylinder 37.
Is transmitted through a rod 38 and is driven to rotate in a horizontal plane as indicated by an arrow, and is fixed in a horizontal direction X by a moving mechanism (not shown) holding an air cylinder 37. It is to be moved at a speed.

In this embodiment, a case where an AC-driven plasma display panel is manufactured will be described as an example. In this AC-driven plasma display panel, a plurality of rod-shaped partitions 10 are provided in parallel on the rear substrate 2 (actually on the partition base layer 9), and each of the front substrate 1 and the rear substrate 2 is provided. By arranging the partitions so as to be orthogonal to each other, the display cells are arranged in a matrix in each intersection.

In the method of manufacturing a plasma display panel according to this embodiment, the barrier ribs are formed in the grooves 14 formed in a predetermined pattern by the photosensitive resist 12 through the respective steps shown in FIGS. The material is deposited by the plasma spraying method, and the sprayed coating 18 is deposited so as to rise from the pattern opening of the photosensitive resist 12. Thereafter, in the polishing step, a portion of the thermal spray coating 18 raised from the surface of the photosensitive resist 12 is scraped off and flattened by using the polishing tool 19, so that the height of the thermal spray coating 18 from the surface of the rear substrate 2 is increased. Make the uniformity.

In the above polishing step, the polishing tool 19
The blower tube 36 and the blower hole 29 are supplied from a compressed air supply source.
The compressed air E is fed into the internal space 28 hermetically sealed by the elastic sheet 24 in the cap member 27, so that the pressure in the internal space 28 is increased as shown in FIG. 22 and elastic sheet 24
Are swelled outside from the opening 21 of the holding member 20. Here, the polishing sheet 22 itself has almost no elasticity, but the elastic sheet 24 made of rubber is superimposed on the back surface (upper surface) of the polishing sheet 22. The whole is deformed into a planar shape under substantially uniform air pressure.

The portion of the polishing sheet 22 that swells from the opening 21 is pressed against the surface to be processed by the air cylinder 37 while rotating under the rotational force of the motor 40, and extends in the longitudinal direction of each bar-shaped thermal spray coating 18. On the other hand, it is linearly moved at a constant speed by a moving mechanism in a direction X orthogonal to the direction. As a result, the portion of the thermal spray coating 18 that protrudes from the surface of the photosensitive resist 12 is efficiently scraped off by the abrasive grains 23 having a high hardness mixed and held in the polishing sheet 22, and the top surface of the thermal spray coating 18 is photosensitive. It is planarized flush with the surface of the resist 12. Here, the back substrate 2 generally has some undulations as shown in an exaggerated manner in FIG. 3, but the photosensitive resist 12 is exposed on the surface of the back substrate 2 regardless of the presence of the undulations. Actually, the thermal spray coating 18 is formed to have exactly the same thickness with respect to the surface of the partition underlayer 9). Regardless, they are all set to the same height.

Immediately after the polishing of a certain processing surface is started with the movement of the polishing tool 19, the polishing sheet 22 mainly comes into contact only with the thermal spray coating 18, and the contact area is small. (Amount of polishing per hour) is high, but when the portion of the thermal spray coating 18 raised from the surface of the photosensitive resist 12 is polished and the top surface of the thermal spray coating 18 becomes the same height as the photosensitive resist 12, the polishing sheet 22 contacts the thermal sprayed coating 18 and the photosensitive resist 12 at the same time, and the contact area suddenly increases, and the photosensitive resist 12 is lower in workability than the material of the partition wall forming the thermal sprayed coating 18. Decreases rapidly.
As a result, the surface of the photosensitive resist 12 maintains the same height with almost no shaving.

In this embodiment, the surface of the photosensitive resist 12 is more reliably prevented from being shaved. That is, the controller (not shown)
When the above-mentioned rapid decrease of the processing rate is detected based on the rapid increase of the current value of 0, the air cylinder 37 is slightly sucked and driven for a predetermined time and the polishing sheet 2 is moved.
The moving mechanism is moved at a constant speed while retracting the workpiece 2 upward such that the workpiece 2 is not machined on the surface to be machined. As a result, the photosensitive resist 12 maintains its height at the time of formation as it is, and each thermal spray coating 18 is polished until it is flush with the photosensitive resist 12 so as to be accurately adjusted to a constant height. In the above-described polishing, it is preferable that a processing liquid such as water is injected between the surface to be processed and the polishing sheet 22 to remove processing debris.

Further, since abrasive grains 23 having high hardness are mixed and held in the polishing sheet 22, the thermal spray coating 18 can be efficiently polished by the abrasive grains 23, and the polishing sheet 22 is rotated in the horizontal direction while being rotated. Moved and sprayed coating 1
8 is automatically polished, so that the polishing of the thermal spray coating 18 can be performed much more efficiently as compared with the case where the operator manually performs the polishing.

Moreover, the polishing sheet 22 is made of an elastic sheet 24.
When the polishing sheet 22 swells by receiving air pressure, a uniform pressure acts on the portion of the polishing sheet 22 that swells from the opening 21 of the holding member 20. That is, since the polishing sheet 22 is pressed against the surface to be processed with a uniform pressing force over the entire surface, the top surface of the thermal spray coating 18 can be finished to an accurate flat surface. Therefore, according to this manufacturing method, it is possible to obtain the partition wall 10 having a constant height and an accurate flat surface and capable of maintaining a stable discharge space of plasma, and a high-quality plasma display. Panels can be manufactured.

The polishing tool 19 repeats polishing while reciprocating between the ends in the orthogonal direction X with respect to each spray coating 18 on the surface to be processed, thereby polishing the entire surface to be processed. That is, when the polishing tool 19 is moved to the end of the surface to be processed along the forward path along the orthogonal direction X, the polishing tool 19 has a direction Y parallel to the longitudinal direction of each thermal spray coating 18 shown in FIG.
Is moved laterally by a predetermined scanning pitch P, and then moved in the return path along the orthogonal direction X to the end of the surface to be processed.
Further, the above-mentioned horizontal movement by the scanning pitch P in the parallel direction Y is repeated, and the entire surface to be processed is polished while reciprocating.

Next, the scanning pitch P will be described with reference to FIG.

Now, the width of the contact area of the polishing sheet 22 with the surface to be processed including the thermal spray coating 18 (in this case, the diameter because the polishing sheet 22 is circular) is W, and the scanning pitch is P. I do. FIG. 4A shows the scanning pitch P
Sprayed coating 18 when is set equal to the width W of the contact area
3 shows the surface condition after polishing in FIG. 3 for comparison, and the polished surface of the thermal spray coating 18 has a scanning pitch P
The seam between them appears, and a wavy polishing unevenness d is generated.
On the other hand, FIG. 3B shows the surface state of the thermal spray coating 18 after polishing when the scanning pitch P is set to approximately 1/4 of the width W of the contact area. No polishing unevenness occurred on the polished surface of No. 18. Polishing unevenness is caused by setting the scanning pitch P to 1 / (the width W of the contact area)
When it is set to 2, it decreases to a slightly conspicuous degree, and decreases as the scanning pitch P is reduced to half or less of the width W. However, the smaller the scanning pitch P, the smaller the polishing unevenness d, but the longer the polishing processing time. Therefore, it is preferable to set an appropriate value within 1/2 of the width W according to the processing condition. . As a result, it is possible to obtain the partition wall 10 that can more stably maintain the plasma discharge space, and to manufacture a high-quality plasma display panel.

Next, a description will be given of an actual example of polishing of the thermal spray coating 18 using the polishing tool 19 described above. The thermal spray coating 18 was formed by spraying and depositing a partition material mainly composed of alumina by a plasma spray method. As the polishing sheet 22, a material in which diamond was mixed and held as abrasive grains 23 was used. The polishing tool 19 is 200 to 400
The sprayed coating 18 was polished by linearly moving the sprayed coating 18 in the orthogonal direction X at a speed of 2 to 10 m / min while rotating at rpm. At this time, water was used as a working fluid. The width W of the contact area of the polishing sheet 22 with the surface to be processed is 35 mm, and the scanning pitch P is 1 of the width W.
/ 7 was set to 5 mm. As a result, the variation in the height of the top surface of the thermal spray coating 18 after the polishing process could be suppressed to an extremely small value of 6 μm or less.

In the above embodiment, the polishing tool 19
Although the case where air is used as a medium for generating a pressure for causing the polishing sheet 22 to bulge out of the opening 21 in the internal space 28 is described as an example, oil or water is used as this medium. It can also be used. However, air is the most preferable as the pressure generating medium because there is no problem even if air leaks. Further, the polishing tool 19 does not necessarily need to be rotated, and is applied to each sprayed coating 18 while giving a relative motion to the work surface including the sprayed coating 18 so as to rotate linearly reciprocally or circularly within a certain range. You may make it move to orthogonal direction X.

[0032]

As described above, according to the method of manufacturing a plasma display panel of the present invention, a polishing tool having a poor elasticity is swelled from an opening by applying pressure through an elastic sheet. Since the thermal spray coating is polished while pressing the polishing sheet of the polishing tool against the surface to be processed, the entire polishing sheet can be pressed with a uniform pressing force against the surface to be processed, and the top surface of the thermal spray coating can be pressed. Can be polished to an accurate flat surface. In addition, when the sprayed coating is polished until it is flush with the resist, the contact area of the polishing sheet becomes large and the processing rate drops sharply, so the top surface of the sprayed coating is resisted while following the undulation of the back substrate itself. Thus, the sprayed coating can be accurately made to have a constant height. As a result, it is possible to obtain a partition wall having a constant height and an accurate flat surface so that a stable discharge space of plasma can be maintained, and a high-quality plasma display panel can be manufactured. . Furthermore, since the polishing of the thermal spray coating is performed while the polishing tool is automatically moved in the horizontal direction, the polishing can be performed much more efficiently than in the case where the polishing is manually performed by an operator.

[Brief description of the drawings]

FIG. 1 is an exploded longitudinal sectional view showing a polishing tool used in a step of polishing a thermal spray coating in a method of manufacturing a plasma display according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view in a state where the polishing tool spray coating of the polishing tool is being polished.

FIG. 3 is a side view showing a state in which the thermal spray coating is being polished by the polishing tool of the above.

FIG. 4 is a longitudinal sectional view showing a polished state of the surface of the thermal sprayed coating after being polished by the above polishing tool;
When the scanning pitch P is set equal to the width W of the contact area,
(B) shows that the scanning pitch P is set to approximately ほ ぼ of the width W of the contact area.
This is the case when set to about.

FIG. 5 is a longitudinal sectional view showing a plasma display panel that can be manufactured by the manufacturing method of the present invention.

FIGS. 6A to 6G are manufacturing process diagrams showing a method of manufacturing the plasma display panel in the same order as in the above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front substrate 2 Back substrate 10 Partition wall 12 Photosensitive resist (resist) 14 Groove 18 Thermal spray coating 19 Polishing tool 21 Opening 22 Polishing sheet 23 Abrasive grains 24 Elastic sheet 28 Internal space W Contact area width P Scanning pitch X Moving direction Y orthogonal direction

Continued on the front page F term (reference) 3C043 BA07 BA11 BB00 CC13 5C027 AA09 5C040 GF19 JA15 JA20 JA23 JA31 LA17 MA24 MA26

Claims (3)

[Claims] 1. A method of manufacturing a plasma display panel having a discharge space separated by a partition wall between a front substrate and a rear substrate arranged opposite to each other, wherein a groove of a predetermined pattern is formed on the rear substrate by a resist. A pattern forming step of forming, a film forming step of depositing a partition wall material in the groove by a plasma spraying method to form a thermal spray coating for forming the partition wall, and polishing a portion of the thermal spray coating raised from the surface of the resist. A polishing step of flattening the top surface of the thermal spray coating to have a predetermined height; and a resist removing step of removing the resist to obtain the partition walls made of the thermal spray coating. Is a method in which a pressure generated in an internal space is applied to a polishing sheet via an elastic sheet to cause the polishing sheet to bulge out of an opening. By using a tool, by pressing the polishing tool while applying relative motion to the surface to be processed of the sprayed coating and the resist and automatically moving the polishing tool in the horizontal direction, the sprayed coating is polished, Of manufacturing a plasma display panel. 2. The polishing sheet according to claim 1, wherein the polishing sheet containing a large number of abrasive grains having a higher hardness than the thermal spray coating is linearly moved in the horizontal direction while being pressed against the surface to be processed while applying a rotational motion. A manufacturing method of the plasma display panel according to the above. 3. The polishing tool linearly reciprocates between both ends of the surface to be processed, and each time the polishing tool is moved to the end, the scanning pitch is equal to or less than half the width of the contact area of the polishing sheet with the surface to be processed. 3. The method of manufacturing a plasma display panel according to claim 1, wherein the lateral movement is performed only in the direction perpendicular to the moving direction.