JP2000123730A - Method for forming fluorescent layer of plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a manufacturing method for fluorescent layers capable of removing a fluorescent material adherent to the tops of barrier ribs when manufacturing the PDP. SOLUTION: When forming fluorescent layers 20, in a fluorescent paste printing process, plural kinds of fluorescent paste are sequentially printed in every discharge space from the tops 22 of barrier ribs 14. In a subsequent baking process, the fluorescent paste is baked to form plural kinds of fluorescent layers 20 on the sides 18 of the ribs 14. Further, in a top fluorescent material removing process, an adhesive 28 provided with adhesion on the surface 30 changing in shape according to the shape of the rib tops 22 is pressed against the tops 22, thereby the fluorescent material adherent to the tops 22 is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma display panel (PDP).
) Of the phosphor layer forming method.

[0002]

2. Description of the Related Art A partition wall protruding from one surface of a substrate to define a plurality of discharge spaces, and a plurality of types of phosphor layers separately applied to the plurality of discharge spaces are provided. 2. Description of the Related Art There is known a PDP in which a discharge is generated inside the phosphor layer, and the phosphor layer is excited by ultraviolet rays generated thereby to emit light. In each of the above-described discharge spaces, for example, any one of three color phosphor layers of red (R), green (G), and blue (B) is provided for multicolor display. Then, for each discharge space defined by the lattice-shaped partition walls, or each of the discharge spaces defined by the elongated partition walls, the discharge spaces are electrically separated by the discharge electrodes provided orthogonally to the partition walls. A plurality of light-emitting sections arranged in a lattice pattern as a whole are configured in each of the ranges that are covered by the above-described range, and desired images such as characters, symbols, and figures are displayed by selectively causing each light-emitting section to emit light. Such a PDP is expected to be an image display device replacing a CRT because it is a flat plate type and can be easily made thin and light.

[0003]

Incidentally, the above-mentioned phosphor layer is generally formed by applying a phosphor paste by thick film screen printing from the top of the partition wall protruding from one surface of the substrate. According to the thick-film screen printing, the manufacturing cost is low and the utilization efficiency of the material is high,
This is because it is easy to apply different phosphor layers. The phosphor paste printed on the partition wall from the top side to the top part thereof flows down while remaining partially on the side wall of the partition wall due to a temporal flow based on rheology (that is, fluidity and surface tension), that is, so-called “ink dripping”. As a result, a phosphor layer is formed on the side surface of the partition wall constituting the inner wall surface of the discharge space and the surface of the substrate with a thickness determined based on the rheology of the phosphor paste.

[0004] However, in the screen printing from the top of the partition wall as described above, it is inevitable that the phosphor paste remains on the top. Therefore, there is a problem that color mixture may occur due to leakage of the light emission of the phosphor remaining on the top into the adjacent discharge space. In addition, when the top of the partition is formed in black for the purpose of functioning as a black mask, there is a problem that the contrast is reduced if the phosphor adheres to the top. Therefore, it has been desired to remove the phosphor remaining on the top of the partition wall, especially for realizing high-definition display.

As a method of removing the phosphor at the top of the partition wall, for example, it is conceivable to perform a polishing process on the top after printing a phosphor paste. However, there is some variation in the height of the partition walls, and furthermore, since there are irregularities on the tops, it is difficult to remove only the phosphor by the polishing process. In addition, it is necessary to form the partition walls higher by the polishing removal height determined according to the height variation and the unevenness of the top.
This is a serious problem because it becomes difficult to uniformly polish the larger the substrate, and it is necessary to set a large removal amount. In addition, there is also a problem that the partitioning of the discharge may be damaged due to the chipping of the partition wall due to the polishing treatment. Further, if polishing dust such as phosphor powder or partition wall material generated by polishing remains in the discharge space, there is a problem that color mixing or black spots may occur. Therefore, the polishing method is impractical and cannot be adopted.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a method for forming a phosphor layer capable of suitably removing a phosphor adhered to the top of a partition when manufacturing a PDP. It is in.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is to provide a partition wall projecting from one surface of a substrate to define a plurality of discharge spaces. When producing a PDP of a type comprising a plurality of types of phosphor layers coated separately for each discharge space and exciting the phosphor layer with ultraviolet light generated by discharging in the discharge space to emit light. A method of forming the plurality of types of phosphor layers on the side surfaces of the partition walls, comprising: (a) a phosphor paste printing step of sequentially printing a plurality of types of phosphor pastes separately from the top of the partition walls for each of the discharge spaces. And (b) baking the phosphor paste to form the plurality of types of phosphor layers on the side surfaces of the partition walls; and (c) after the baking step, having a sticky surface and Top shape of partition wall Modeled by the by pressing the elastic adhesive layer is deformed its surface on its top portion, a phosphor removal step of removing the phosphor attached to its top, and is meant to include.

[0008]

In this way, in forming the phosphor layer, in the phosphor paste printing step, a plurality of types of phosphor pastes are sequentially applied from the top of the partition walls for each discharge space, and are successively printed. In the firing step, the phosphor paste is fired to form a plurality of types of phosphor layers on the side surfaces of the partition walls. Further, in the phosphor removing step after the firing step, the surface has adhesiveness and By pressing an elastic adhesive layer whose surface is deformed according to the shape of the top against the top, the phosphor adhering to the top is removed. For this reason, the phosphor paste is also attached to the top by printing from the top of the partition wall, but when baking is performed, the organic components contained in the phosphor paste are removed, so that the phosphor particles are separated from each other. Since the bonding force is reduced, the phosphor adhered to the top is removed from the top by sticking to the surface when the elastic adhesive layer is pressed against the top. At this time, since the elastic adhesive layer has an adhesive surface deformed following the shape of the top, even if unevenness or a height difference occurs at the top of the partition wall, the surface is brought into close contact with the top, so The attached phosphor powder is also suitably adsorbed to the elastic adhesive layer. Therefore, when forming the phosphor layer, the phosphor adhering to the top of the partition can be suitably removed without performing a polishing treatment.

[0009]

In another preferred embodiment of the present invention, (c-2) the step of removing the phosphor is to roll a roller having the elastic adhesive layer on the outer peripheral surface thereof on the top of the partition. In this way, in the phosphor removal step, the roller having the elastic pressure-sensitive adhesive layer provided on the outer peripheral surface is rolled on the top of the partition to remove the phosphor attached to the top. Therefore, the phosphor adhered to the top portion can be easily removed by a simple operation of rotating the roller while pressing it toward the top of the partition wall with an appropriate force and sending the roller in one direction.

In the case where the elastic pressure-sensitive adhesive layer is provided on the outer peripheral surface of the roller, preferably, the partition walls are formed in a longitudinal shape and are arranged along one direction. The roller is rolled in a direction substantially along the longitudinal direction. With this configuration, since the roller is rolled in a direction substantially along the longitudinal direction of the partition, the force acting in the width direction of the partition is reduced, and the partition is damaged by pressing the roller. Is suitably suppressed.

Preferably, (c-3) in the phosphor removing step, a sheet provided with the elastic pressure-sensitive adhesive layer on one surface is brought into close contact with the top of the partition wall and peeled off. In this way, in the phosphor removal step, the sheet provided with the elastic adhesive layer on one surface thereof is brought into close contact with the top of the partition and peeled off, whereby the phosphor attached to the top is removed. That is, the shape of the elastic pressure-sensitive adhesive layer may be a flat sheet shape in addition to the cylindrical shape provided on the outer peripheral surface of the roller.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1A is a diagram showing a back plate 10 of an AC type color PDP to which the phosphor layer forming method of the present invention is applied. The back plate 10 is made of, for example, a flat plate made of soda lime glass, and has a plurality of elongated partition walls (rib-like walls) 14 projecting in parallel from each other at a certain interval on one surface 12 thereof. Has been established. These plural partitions 1
Numeral 4 is provided for partitioning a plurality of elongated discharge spaces 16 in an airtight space formed between the back plate 10 and a front plate (not shown) disposed on the one surface 12 side. a is, for example, B ₂ O _3, low softening point glass of PbO-based, etc., an inorganic filler such as alumina or zirconia (filler), and a black inorganic pigment, such as Cu-Cr-Mn or Fe-Cr-Mn It has a black color and is porous. In the present embodiment, the back plate 10 corresponds to a substrate.

On the inner wall surface of the discharge space 16, that is, on one surface 12 of the back plate 10 and on the side surface 18 of the partition wall 14, the phosphor layers 20R, 20 painted separately for each discharge space 16 are formed.
G and 20B are provided with a thickness determined for each color within a range of, for example, about 50 (μm) or less. The phosphor layer 20 is made of, for example, R (red), G
It is made of a phosphor corresponding to a luminescent color such as (green), B (blue), etc., and is provided so that three colors are arranged in order so that adjacent discharge spaces 16 have different luminescent colors. Also, as shown in FIG. 1B, the phosphor layer 20 is
Is provided in a range lower than the top 22 by, for example, about h = 10 (μm), and the exposed top 22 is provided.
Has no phosphor attached. Therefore, the partition 14
In a state where a front plate (not shown) is disposed on the top portion 22 of the discharge space, the phosphor layer 20 provided in each discharge space 16 is sufficiently separated from the adjacent discharge space 16. Color mixing resulting from leakage of light emitted from the phosphor layer 20 is suitably suppressed. Moreover, since the tops 22 of the partition walls 14 exhibiting black are exposed, the partition walls 14 can suitably function as a black mask, so that the contrast is enhanced.

The back plate 10 has a write electrode for selecting a discharge cell, an undercoat and an overcoat for suppressing a reaction between the write electrode and the back plate 10 or the phosphor layer 20. -Coats and the like are provided as necessary, but these are omitted because they are not necessary for understanding the present embodiment.

The phosphor layer 20 is provided, for example, according to the process shown in FIG. First, in the partition forming step S1, the partition 14 is projected on the back plate 10 by using a well-known method such as a thick film screen printing or a sand blast method. Next, in a phosphor paste printing step S2, a phosphor paste in which phosphor particles are dispersed in a vehicle in which a resin component is dissolved in an organic solvent is applied to the partition wall 1 by using thick film screen printing.
4. Apply from above. In the subsequent drying step S3, the solvent in the paste is removed by performing a drying process on the back plate 10 to which the phosphor paste has been applied. The phosphor paste printing step S2 and the drying step S3 are performed for each phosphor color by using different screen printing plates. Therefore, in the case where three colors of RGB are separately applied, the number of repetitions is three.

After the phosphor paste is applied to all of the discharge spaces 16 as described above, in a firing step S4, a heat treatment is performed at a temperature determined according to the type of the resin component and the phosphor particles. As a result, the resin component in the paste is removed, and the phosphor layer 20 in which the phosphor particles are mutually bound by a relatively weak binding force such as an intermolecular force is generated. FIG.
(a) and FIG. 4 (a) show this state. At this time, in the screen printing method for applying the phosphor paste, the paste extruded from the screen is adhered to the top 22 while the screen is in close contact with the top 22 of the partition wall, and the flow over time based on the rheology of the paste itself is performed. As shown in the figure, the phosphor layer 20 is also provided on the top portion 22 of the partition wall 14 at the stage immediately after the baking, as shown in the drawing. That is, the phosphor layer 20 is formed in the adjacent discharge space 1.
6 are overlapped at their tops 22, and the tops 22 are covered with the phosphor layer 20 and are not exposed.

Therefore, in the subsequent top phosphor removing step S5, the phosphor adhering to the partition top 22 is removed, so that the top 22 is exposed. The removal of the phosphor is performed by removing the phosphor removing roller 2 as shown in FIG.
4 on the top 22 thereof in the direction of the arrow in the figure, ie along the longitudinal direction of the partition 14. Since the roller 24 is pressed against the partition wall 14 by a relatively small force such as its own weight, the partition wall 14 is not damaged when the roller 24 is rolled. In this embodiment, the top phosphor removing step S5 corresponds to the phosphor removing step.

The above-mentioned phosphor removing roller 24 is made of, for example, a cylindrical or cylindrical core material 26 made of aluminum or FRP.
An adhesive 28 made of a material that can be easily elastically deformed, such as a polymer rubber adhesive such as silicone resin, SBR, resorcinol, or natural rubber, is provided on the outer peripheral surface of the adhesive.
(cm). That is, the surface of the phosphor removing roller 24, that is, the surface 30 of the adhesive 28 has an adhesive property and the shape of the top 22 of the partition wall 14 based on the elasticity of the adhesive 28 itself as shown in FIG. It is designed to be deformed according to. In this embodiment, the pressure-sensitive adhesive 28 corresponds to an elastic pressure-sensitive adhesive layer.

Therefore, the phosphor layer 20 which has been subjected to the calcination treatment as described above has a weak binding force between the phosphor particles 32, so that the phosphor removing roller 24 is brought into close contact with the top 22 of the partition wall 14. Then, the phosphor particles 32 are adhered to the surface 30 of the roller 24 having adhesiveness and are removed from the partition wall 14. At this time, the surface 30 is deformed according to the shape of the top portion 22 and is closely attached thereto, so that even if the top portion 22 has unevenness or a variation in height, the height of the partition wall 14 is equal to or more than a certain height. The phosphor particles 32 adhering to the position are surely removed. That is, as shown in FIG. 4B, the phosphor removing roller 24 removes excess phosphor particles from the top 22 by rolling while attaching the phosphor particles 32 to the surface 30 thereof. FIG. 3C shows a state after the phosphor on the two partition walls 14 located on the left side is removed in this manner, and the phosphor particles adhered within the width of the partition wall 14. 32 is removed to expose the partition top 22. Therefore, the PDP using the back plate 10 is provided with a black mask having a substantially uniform width dimension equal to the width dimension of the partition wall 14.

The portion of the surface 30 of the adhesive 28 to which the phosphor particles 32 adhere is reduced or lost in tackiness. Therefore, the phosphor particles 32 are adsorbed on the portion to be removed therefrom and removed from the top 22 of the partition wall. I can't. However, the phosphor particles 32 adhered to the surface 30 of the roller 24
Can be removed by wiping the surface 30 with alcohol or the like, or by transferring the surface 30 with an adhesive tape or the like having the same properties as the adhesive 28. Therefore, the roller 24 can be repeatedly used by appropriately removing the phosphor particles 32. Although the roller 24 is drawn in a columnar shape with a relatively small diameter in the drawing, the diameter is actually determined so that the circumference is longer than the longitudinal dimension of the partition 14. By rolling from one end to the other in the longitudinal direction, the phosphor particles 32 on the top 22 are removed over the entire length in the longitudinal direction by one operation. For example, when the length of the partition 14 is about 1 (m), the roller 24 having a diameter of about 35 (cm) or more on the surface 30 is used.

In short, in this embodiment, when forming the phosphor layer 20, the phosphor paste printing step S
2, a plurality of types of phosphor pastes are sequentially printed from the top 22 of the partition wall 14 separately for each discharge space 16,
In the subsequent firing step S4, the phosphor paste is fired to form a plurality of types of phosphor layers 20 on the side surfaces 18 of the partition walls 14. Further, in the top phosphor removing step S5 after the firing step S4, the surface is removed. By pressing an adhesive 28 having an adhesive property on the top 30 and deforming its surface 30 according to the shape of the partition top 22, the phosphor adhered to the top 22 is removed. Therefore, the phosphor paste is also attached to the top portion 22 by printing from the top portion 22 side of the partition wall 14, but when baking is performed, the organic component contained in the phosphor paste is removed, so that the phosphor paste is removed. Since the bonding force between the body particles 32 is reduced, the phosphor adhered to the top 22 is removed from the top 22 by sticking to the surface 30 when the adhesive 28 is pressed against the top 22. At this time, the adhesive 28 has the adhesive surface 30.
Is easily elastically deformed in accordance with the shape of the top 22, so that even if the top 22 of the partition wall 14 has irregularities or a height difference, the surface 30 is brought into close contact with the top 22, so that the fluorescent light adhering to the recess is formed. The body particles 32 are also suitably bonded to the adhesive 28. Therefore, when the phosphor layer 20 is formed, the phosphor adhered to the partition wall top 22 can be suitably removed without performing a polishing process.

Further, in this embodiment, in the top phosphor removing step S5, the roller 24 provided with the adhesive 28 on the outer peripheral surface is rolled on the top 22 of the partition wall 14 so as to adhere to the top 22. Phosphor is removed.
Therefore, the phosphor adhered to the top portion 22 can be easily removed by rotating the roller 24 while pressing it against the top portion 22 of the partition wall 14 by its own weight.

In the present embodiment, the partition walls 14 are longitudinally arranged in one direction, and the top phosphor removing step S5 is to roll the roller 24 in the direction along the longitudinal direction. Things. Therefore, since the roller 24 is rolled in the direction along the longitudinal direction of the partition 14, breakage of the partition 14 caused by pressing the roller 24 is further suppressed.

The removal amount of the phosphor layer 20, that is, the height h shown in FIG. 1B can be appropriately set by changing the configuration and the method of use of the roller 24. That is, when it is desired to increase the height h, the pressure-sensitive adhesive 28 is made of a more easily deformable material such as soft rubber or silicone rubber, and the thickness t is increased, or the pressure t
Press force) can be increased. Conversely, when the height h is to be reduced, the pressure-sensitive adhesive 28 is made of a hardly deformable material such as a hard rubber or a soft rubber to which a filler is added, and the thickness t is reduced. Should be lowered. In FIG. 3B, the roller 24 indicated by a dashed line is shown.
Is an example in which the thickness t of the adhesive 28 is reduced. As the thickness t decreases, the amount of deformation of the adhesive 28, that is, the size of the depression decreases. Therefore, as shown by a dashed line at the right end of FIG. 3C, the removal amount of the phosphor layer 20 is smaller than that in the case where the roller 24 having a large thickness t is used. When it is desired to increase the area where the phosphor layer 20 is provided as much as possible in a range where color mixing is unlikely to occur, the removal amount of the phosphor may be controlled in this manner.

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. 5 is a view for explaining another embodiment of the top phosphor removing step S5. In the figure, partition 1
A phosphor removing sheet 34 is adhered to the top 22 of the fourth member 4 instead of the roller 24. The sheet 34 is, for example,
An adhesive 28 similar to that of the roller 24 is provided on one surface of a back-up 36 made of paper, a resin sheet, or the like, and the whole is flexible. When removing the fluorescent material on the top portion 22 using such a sheet 34, first, as shown by a dashed line in FIG.
The surface 30 of the adhesive 28 of the sheet 34 is brought into close contact therewith. At this time, the pressure-sensitive adhesive 28 is deformed into a shape following the top 22 of the partition wall, as shown in FIG. . Thereafter, for example, the sheet 3 is moved from one end shown on the left side of the drawing to the direction shown by the arrow P in the drawing.
Peel 4 off. Thereby, the adhesive 28 of the sheet 34 is
The phosphor particles 32 adhering to the top 22 are adhered and removed similarly to the case of the roller 24, and the back plate 10 shown in FIG. 1 is obtained. In short, the top phosphor removing step S5 can be similarly performed by using the sheet 34 configured as described above instead of the roller 24.

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 other embodiments.

For example, in the embodiment, the back plate 10 provided with the stripe-shaped partition walls 14 arranged in one direction.
Although the case where the phosphor layer 20 is provided above has been described, the present invention is similarly applied to a case where the partition walls 14 form a lattice shape.

In the embodiment, the surface 30 is deformed following the shape of the top portion 22 by elastically deforming the adhesive 28 itself. However, the adhesive layer 28 is thinly provided and provided on the back surface thereof. When the support, for example, the core material 26 and the back-up 36 are elastically deformed, the adhesive layer 28 provided on the surface thereof substantially becomes the top 2.
2, it may be configured to be deformed.

Further, without providing a support such as the core material 26 and the back-up 36, the fluorescent material removing roller 2 is formed only by the adhesive layer 28.
4 and the phosphor removal sheet 34.

In the embodiment, phosphors of three colors of R, G, and B are used, but the color and the number of colors of the phosphors used are appropriately changed according to the use of the PDP. The present invention is similarly applied to a case where the phosphor layers 20 of two colors or four or more colors are separately applied as long as color mixing can occur due to the phosphor remaining on the top 22.

In the embodiment, the baking step S4 for forming the phosphor layer 20 from the phosphor paste is performed after all the three color phosphor pastes are applied. However, the baking process is performed for each color. It can be applied. In this case, the top phosphor removing step S5 can be performed for each color after the baking process.

Further, in the embodiment, the roller 24 is rolled along the longitudinal direction of the partition wall 14. However, the roller 24 may be rolled in a direction slightly inclined with respect to the longitudinal direction. In this way, the position of the surface 30 that contacts the partition wall 14 gradually changes in the axial direction of the roller 24, and the fluorescent particles 32 are spirally formed on the surface 30.
Is attached, so that the diameter of the roller 24 necessary for removing the phosphor attached to the top portion 22 in one scan can be reduced.

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

[Brief description of the drawings]

FIG. 1A is a perspective view showing a back plate of a PDP to which a phosphor layer forming method of the present invention is applied, and FIG. 1B is a cross-sectional view perpendicular to the longitudinal direction of the partition wall in FIG. FIG.

FIG. 2 is a process diagram illustrating a method for forming a phosphor layer on the back plate of FIG.

3 (a) to 3 (c) are cross-sectional views of main parts showing states of a back plate at each stage of the process of FIG. 2;

4 (a) is a view showing a state after a firing step of FIG. 2, and FIG. 4 (b) is a view showing a state during a top phosphor removing step.

FIG. 5 is a diagram corresponding to FIG. 4 (b) for explaining another embodiment of the present invention.

[Explanation of symbols]

 10: Back plate (substrate) 14: Partition wall 20: Phosphor layer 22: Top 28: Adhesive 30: Surface

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C028 FF16 HH14 5C040 FA01 GB02 GG03 GG09 JA09 JA12 JA23

Claims (4)

[Claims] 1. A discharge space comprising: a partition wall protruding from one surface of a substrate to form a plurality of discharge spaces; and a plurality of types of phosphor layers separately applied to the plurality of discharge spaces. When manufacturing a plasma display panel of a type in which the phosphor layer is excited by ultraviolet rays generated by discharging in the chamber to emit light, the plurality of types of phosphor layers are formed on side surfaces of the partition walls. A phosphor paste printing step of applying a plurality of types of phosphor paste from the top of the partition wall separately for each discharge space and sequentially printing the phosphor paste, and firing the phosphor paste to form the plurality of types of phosphor paste on a side surface of the partition wall. A sintering step of forming a phosphor layer, and after the sintering step, pressing an elastic adhesive layer having an adhesive surface and deforming the surface according to the shape of the top of the partition wall against the top. A phosphor removing step of removing the phosphor adhered to the top portion. A method for forming a phosphor layer of a plasma display panel, comprising: 2. The method for forming a phosphor layer of a plasma display panel according to claim 1, wherein the step of removing the phosphor comprises rolling a roller provided with the elastic adhesive layer on the outer peripheral surface thereof on the top of the partition wall. . 3. The partition wall has a longitudinal shape and is arranged along one direction, and the phosphor removing step includes rolling the roller in a direction substantially along the longitudinal direction. Method for forming a phosphor layer of a plasma display panel. 4. The phosphor layer of the plasma display panel according to claim 1, wherein the phosphor removal step comprises peeling a sheet provided with the elastic adhesive layer on one surface thereof in close contact with the top of the partition wall. Forming method.