JPH05182592A - Plasma display panel and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve productivity of a plasma display panel to enhance its yield and to better luminance efficiency. CONSTITUTION:Cell barriers 9 are formed by a phosphor paste containing frit and discharge spaces are formed by independent cell barriers 9. A method of manufacturing a plasma display panel includes the process of forming on a base a mold corresponding to the area of the cell barriers 9, the process of filling the space of the mold with a phosphor paste containing frit, and the process of burning the mold out to form cell barriers 9 from phosphor. The method can greatly shorten the time required for processing as compared with conventional thick film pattern lamination methods. Since the barriers 9 themselves are excited and emit light, luminance efficiency is enhanced. Each of the discharge spaces is formed by independent red, green and blue cell barriers 9, whereby a color plasma display panel can readily be manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel (hereinafter referred to as PDP) having a plurality of discharge spaces formed by cell barriers and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 9 shows one configuration example of a conventional DC PDP. As shown in the figure, in this DC type PDP, a flat front plate 31 made of glass is used.
The back plate 32 and the back plate 32 are arranged in parallel and opposite to each other, and both of them are held at a constant interval by a cell barrier 33 provided therebetween. Further, an anode 34 is formed on the back side of the front plate 31, and the back plate 3
A cathode 35 is formed on the front surface side of 2 perpendicularly to the anode 34, and a phosphor screen 36 is formed adjacent to both sides of the anode 34. In this PDP, the anode 34 and the cathode 3
A predetermined voltage is applied from a DC power supply between the two to form an electric field, whereby the front plate 31, the rear plate 32, the cell barrier 3
Discharge is performed inside each cell 37 as a display element composed of 3 and 3. Then, the ultraviolet rays generated by this discharge cause the fluorescent surface 36 on the back side of the front plate 31 to emit light, and the observer visually recognizes this light transmitted through the front plate 31.

The fluorescent screen 36 of the PDP as described above is
Generally, it is formed by applying a photosensitive slurry liquid containing a phosphor on the back surface of the front plate, exposing it using a photomask corresponding to the pattern of the phosphor screen, and then developing and baking it. As the photosensitive slurry, for example, a mixture containing a phosphor, polyvinyl alcohol (PVA) and a diazonium salt is used, and a defoaming agent or a surfactant may be added depending on the case.

In the PDP having the above-mentioned structure, the light emitted from the fluorescent screen 36 passes through the fluorescent screen 36 itself and is visually recognized by an observer. become. For this reason, for the purpose of increasing the brightness, a PD in which a fluorescent surface is formed on the wall surface of the cell barrier 33 and the reflected light of the light emitted from the wall surface is directly viewed
P is proposed. As a method for obtaining such a PDP, for example, a phosphor screen forming method described in Japanese Patent Laid-Open No. 1-313837 is known.

The procedure of this phosphor screen forming method is shown in FIGS.
4 shows. In this method, first, as shown in FIG. 10, a phosphor slurry liquid 44 is filled into the inside of a cell barrier 43 formed so as to straddle the cathode 42 on the back plate 41, and then the back plate as shown in FIG. Lean 41 vertically. In this state, as shown in FIG. 12, the phosphor 44a contained in the phosphor slurry liquid 44 is allowed to stand until it settles on the wall surface of the cell barrier 43, and then dried, so that the cell barrier 43 of the cell barrier 43 as shown in FIG. The phosphor 44a is attached to the wall surface. Then, by using a negative photosensitive liquid as the phosphor slurry liquid 44, the mask 4 is formed as shown in FIG.
It is possible to perform oblique exposure so that only the wall surface of the cell barrier 43 is exposed to the ultraviolet rays 46 through 5, and to cure only the phosphor 44a on the wall surface of the cell barrier 43, and then to develop the phosphor screen on the wall surface. Can be formed. This is repeated four times to form fluorescent screens on the four surfaces of the cell barriers 43 partitioned in a matrix. Then, this operation is performed for red (R), green (G), and blue (B) to form a phosphor screen of three primary colors.

[0006]

However, the above-described phosphor screen forming method requires a total of 12 times of filling of the phosphor slurry liquid and selective exposure through the mask from an oblique direction. Since the phosphor is long and complicated, and it takes a long time to settle the phosphor, there is a problem that it takes a huge amount of time to complete the phosphor screen. Also,
The unevenness of the cell barrier height is reflected in the oblique exposure process, and there is also a problem that it is difficult to pattern the stable fluorescent surface. In order to adopt a curing method using ultraviolet rays, the thickness of the fluorescent material is less than 20 μm. There is also a problem that a satisfactory luminance efficiency cannot be obtained. Furthermore, the barrier forming step and the phosphor screen forming step are completely separated, which is a cause of poor productivity and reduced yield.

On the other hand, the cell barrier on which the fluorescent screen is formed is usually formed by screen printing. In this case, a paste in which a ceramic material is dispersed in a binder needs to be overprinted by screen printing a plurality of times to obtain a predetermined thickness.
Overprinting is required 5 to 10 times to obtain a film thickness of ˜100 μm, and a drying step is required each time. Since the barrier forming step and the phosphor screen forming step are separate steps, there is a problem in that the steps are complicated and the productivity is extremely deteriorated.

The present invention has been made to solve the above problems, and provides a plasma display panel which can improve productivity and yield, and has good luminance efficiency. It is intended to provide a manufacturing method.

[0009]

To achieve the above object, in a PDP of the present invention, a front plate and a rear plate having cell barriers forming a plurality of discharge spaces are opposed to each other in parallel. In the plasma display panel arranged as described above, by forming the cell barrier with a phosphor paste containing glass frit, the cell barrier itself serves as a phosphor screen, and each discharge space is formed by an independent cell barrier. It has a feature.

In the case of color display, a plurality of cell barriers constituting one pixel for color display are connected with red,
A pattern is formed using green and blue phosphors.

In the method of manufacturing a PDP having the above-mentioned structure, a step of forming a female mold corresponding to a cell barrier region on a substrate, and a step of filling the space of the female mold with a phosphor paste containing glass frit. And a step of forming a cell barrier made of a phosphor by eliminating the female mold. Then, in this manufacturing method, the step of forming the female mold can be achieved by a step of providing a photoresist layer on the substrate and a step of performing pattern exposure and development on the photoresist layer.

Another method of manufacturing the PDP having the above structure is to form a female mold corresponding to a region including a cell barrier and a discharge space on a substrate, and to form a glass frit in the female mold space. Filling the containing phosphor paste, forming a discharge space by sandblasting through a sandblasting mask provided with a window corresponding to the discharge space, and disappearing the female mold Accordingly, a step of forming a cell barrier by a phosphor is provided. Further, in this manufacturing method, the step of forming the female mold can be achieved by a step of providing a photoresist layer on the substrate and a step of performing pattern exposure and development on the photoresist layer, The step of forming a sandblasting mask can be achieved by a step of providing a photoresist layer on the female mold and a step of performing pattern exposure and development on the photoresist layer.

[0013]

According to the above-described PDP of the present invention, since the cell barrier is formed of the phosphor paste containing the glass frit, the wall surface of the cell barrier directly serves as the phosphor screen, and as a result, the luminance efficiency is remarkably enhanced.

Further, in the manufacturing method of the present invention, the method of forming the cell barrier by the phosphor is performed by forming the resist female mold by the photolithography method and filling the space with the phosphor paste. The cell barrier of the film thickness is formed by a simple process, and the productivity is remarkably improved.

[0015]

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

[Embodiment 1] FIG. 1 shows a process of forming a cell barrier in a PDP as an embodiment of the present invention.

First, as shown in FIG. 1A, pitches 5 are formed by screen printing on a glass substrate 1 to be a back plate.
A Ni electrode having a size of 00 μm and a line width of 200 μm was printed, dried and fired to form a cathode 2. Then, after cleaning the glass substrate, a photoresist layer 3 having a film thickness of 160 μm was formed as shown in (b). In this example, a photo-curable dry film (Nopco Cure F-5040 manufactured by San Nopco Ltd.) was used as the photoresist forming the photoresist layer 3, and four layers were laminated to a predetermined film thickness. However, this selection does not limit the present invention, and an appropriate photoresist may be appropriately selected depending on the desired pattern size, the type of pattern forming material, and the suitability as a female mold.

Then, as shown in (c), a parallel light printer using an ultrahigh pressure mercury lamp as a light source was used to perform pattern exposure with ultraviolet rays 5 through a photomask 4 corresponding to a desired pattern. The pattern of the photomask 4 used is shown in FIG. 2, in which the shaded mask portion 4a corresponds to the shape of the cell barrier, and the white portion 4b corresponds to the female shape. The widths of the mask portion 4a and the white portion 4b are each 100 μm, and the photomask 4 is arranged in alignment with the cathode 2 shown by the dotted line as shown in the drawing at the time of exposure. The exposure conditions are an intensity of 800 μW / cm ² and an irradiation amount of 200 mJ / when measured at 365 nm.
cm ² . In the subsequent developing step shown in (d), 1,
Spray development was performed with 1,1-trichloroethane at a liquid temperature of 25 to 30 ° C. Through the above steps, the female mold 3a having a desired pattern was obtained with the resist. Then, after a drying step, the phosphor paste 6 was filled into the female mold 3a.

Here, in the case of creating a monochrome PDP,
As shown in (e), a squeegee 7 is used to fill the phosphor paste 6 to form a monochromatic cell barrier. In the case of a color PDP, R, G, B3 are used.
It is necessary to print different color phosphors. For example, when performing patterning as shown in FIG. 3, R, G, and B are separately printed using screen plates 8R, 8G, and 8B as shown in FIG. That is, first, in the step shown in (a), R
The phosphor paste 6R is filled with a squeegee 7 using a screen plate 8R corresponding to the opening pattern of the female mold 3a. Next, after a drying step, the G phosphor paste 6G as shown in (b) and the B phosphor paste 6B as shown in (c) are similarly filled and dried to show R, G, and B.
The phosphor paste pattern was formed.

The phosphors usable in the present invention include red Y ₂ O ₃ : Eu and Y ₂ SiO ₅ : E.
_{u, Y 3 Al 5 O 12} : Eu, Zn 3 (PO 4) 2: M
n, YBO ₃ : Eu, (Y, Gd) BO ₃ : Eu, Gd
_{BO 3: Eu, ScBO 3:} Eu, LuBO 3: There is Eu or the like, Y ₂ SiO ₅ as a blue: Ce, CaWO _4:
Pb, BaMgAl ₁₄ O ₂₃ : Eu and the like, and green as Zn ₂ SiO ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, SrA.
_{l 13 O 19: Mn, CaAl} 12 O 19: Mn, YBO 3: T
b, BaMgAl ₁₄ O ₂₃ : Mn, LuBO ₃ : Tb, G
dBO ₃ : Tb, ScBO ₃ : Tb, Sr ₆ Si ₃ O ₃
Cl ₄ : Eu, etc.

As the binder used in the phosphor paste, ethyl cellulose, rosin, etc. can be used, and as the solvent, butyl carbitol acetate (BC
A) etc. can be used. The amount of phosphor in the paste is 40 to 80% by weight, the glass frit is 5 to 15% by weight, and the balance is binder and solvent. Here, the ratio of the binder to the solvent is preferably 2: 8 to 1: 9 (weight ratio).

The phosphor paste used in this example is 65% by weight of Zn ₂ SiO ₄ : Mn (green) as a phosphor.
A low melting point type glass frit is 10% by weight, and a solution of ethyl cellulose and BCA mixed at a ratio of 1: 9 (weight ratio) has a composition of 25% by weight. For blue and red, only the phosphor is blue and BaMgAl ₁₄ O ₂₃ : Eu, and red for (Y, Gd) BO ₃ : Eu.

Next, as in the case of a monochrome PDP and a color PDP, as shown in FIG. 1 (f), firing is performed under the conditions of a peak temperature of 440 ° C. and a holding time of 10 to 20 minutes to obtain a phosphor. At the same time as the glass substrate 1 was brought into close contact with the glass substrate 1, the resist forming the female mold 3a was burned off to obtain a cell barrier 9 having a desired pattern of the phosphor. The pattern of the cell barrier 9 thus obtained is shown in FIG.

[Embodiment 2] FIG. 6 shows a step of forming a cell barrier in a PDP as another embodiment of the present invention.

First, as shown in FIG. 6A, a Ni electrode having a pitch of 300 μm and a line width of 100 μm is printed on the glass substrate 11 to be a back plate by screen printing.
The cathode 12 is formed by drying and baking, and then a photoresist layer 13 having a film thickness of 160 is formed in the same manner as in Example 1.
1 μm thick, and then UV light 1
5 pattern exposure and then development, (b)
As shown in (3), a female mold 13a having a desired pattern with a photoresist was obtained. The pattern of the photomask 14 used at the time of exposure is shown in FIG.
4a corresponds to the region including the cell barrier and the discharge space, and the white portion 14b corresponds to the shape of the female mold 13a. The side of the mask portion 14a is 200 μm,
The white portion 14b has a width of 100 μm, and the photomask 14 is arranged so as to be aligned with the cathode 12 shown by a dotted line as shown in the drawing at the time of exposure. In this embodiment, due to the relationship between the short pitch of the female mold 13a and the viscosity of the phosphor paste filled in the female mold 13a, when the female mold is formed on the electrode 22 as in the first embodiment, the Body paste cannot be filled completely. Therefore, the photomask 14 shown in FIG. 7 has a pattern shape such that the female mold is not formed on the electrode 12. Next, as shown in (c), the phosphor paste 16 was filled in the female mold 13a in a state where R, G, and B were patterned using the screen plate as shown in FIG. The composition of the three color phosphors used is the same as in Example 1.

After the phosphor paste 16 is dried,
As shown in (d), a sandblasting mask 17 is formed on the top thereof. In this embodiment, the mask 17 for sandblast is formed using photoresist. And
A photocurable dry film (OSBR film manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used as the photoresist. However, this selection does not limit the present invention, and an appropriate photoresist may be appropriately selected depending on the desired pattern size, type of pattern forming material, and suitability as a mask for sandblasting.

The procedure for making the sandblasting mask 17 in this embodiment is as follows. First, the substrate 11 after being filled with the phosphor paste 16 is heated to 50 to 80 ° C., the dry film as a photoresist is laminated, and then pattern exposure is performed with ultraviolet rays through the photomask 18 shown in FIG. It was In FIG. 8, the shaded mask portion 18a having a side of 100 μm corresponds to the discharge space, and during exposure, this mask portion 18a is formed.
Are aligned so as to be aligned with the cathode 12 shown by the dotted line and are located in the center of the female mold 13a shown in the lattice form by the dotted line. The exposure condition is an intensity of 80 when measured at 365 nm.
The irradiation amount is 0 μW / cm ² , and the irradiation dose is 70 mJ / cm ² . Subsequently, in the developing step, anhydrous sodium carbonate 0.2 wt /%
Spray development was performed with an aqueous solution at a liquid temperature of 30 to 50 ° C. Through the above steps, the sandblasting mask 17 shown in (d) was obtained.

Then, after a drying step, as shown in (e), an unnecessary portion is removed by sandblasting 19. Here, glass beads # 600 is used as an abrasive.
By carrying out sandblasting treatment with a jet pressure of 1 kg / cm ² , a discharge space of the cathode 12 could be formed as shown in (f). Under this condition, since the cathode 12 has already been fired, the surface can be treated without damage. In the subsequent step (g), firing is performed under conditions of a peak temperature of 440 ° C. and a holding time of 10 to 20 minutes to bind the phosphor onto the glass substrate 11 and at the same time burn out the female mold 13a and the sandblasting mask 17. , A cell barrier 20 made of a phosphor having a desired pattern
was gotten.

[0029]

Since the present invention is configured as described above, it has the following effects.

The plasma display panel of the present invention is
Since the cell barrier is formed with a phosphor paste containing glass frit, the cell barrier itself is excited by the ultraviolet rays generated by plasma discharge, and the barrier itself is excited to emit light. Therefore, the luminance efficiency can be improved. Since each discharge space is formed by an independent cell barrier, the barrier can be formed of red, green, and blue phosphors, and thus a color PDP can be easily manufactured.

According to the method for manufacturing a plasma display panel of the present invention, a thick film pattern having a height of 100 μm or more can be obtained by a simple process. Since the photolithography method is adopted, the dimensional accuracy and consistency of the pattern can be improved. Moreover, since the process of forming the cell barrier and the phosphor screen can be performed at the same time, the process can be significantly shortened and the productivity can be improved.

[Brief description of drawings]

FIG. 1 is a process diagram of forming a cell barrier in a plasma display panel as an embodiment of the present invention.

FIG. 2 is a diagram showing a pattern of a photomask used for forming a female mold with a photoresist in the step shown in FIG.

FIG. 3 is a diagram showing an example of patterns of red, green, and blue phosphors.

FIG. 4 is a process diagram illustrating a method of printing a phosphor paste by using a screen plate.

FIG. 5 is a perspective view showing a part of a cell barrier.

FIG. 6 is a process drawing of forming a cell barrier in a plasma display panel as another embodiment of the present invention.

7 is a diagram showing a pattern of a photomask used for forming a female mold with a photoresist in the step shown in FIG.

8 is a diagram showing a pattern of a photomask used for forming a mask for sandblasting with a photoresist in the step shown in FIG.

FIG. 9 is a partial cross-sectional view showing a configuration example of a conventional plasma display panel.

FIG. 10 is an explanatory diagram showing a first step of a conventional phosphor screen forming method.

11 is an explanatory diagram showing a step that follows FIG. 10. FIG.

FIG. 12 is an explanatory diagram showing a step that follows FIG. 11.

FIG. 13 is an explanatory diagram showing a step that follows the step of FIG.

FIG. 14 is an explanatory diagram showing a step that follows FIG.

[Explanation of symbols]

 1 Substrate 3 Photoresist Layer 3a Female 6 Phosphor Paste 9 Cell Barrier 11 Substrate 13 Photoresist Layer 13a Female 16 Phosphor Paste 17 Sandblast Mask 19 Sandblast 20 Cell Barrier

Claims (7)

[Claims] 1. A plasma display panel in which a front plate and a rear plate having cell barriers forming a plurality of discharge spaces are arranged so as to face each other in parallel.
The plasma display panel, wherein the cell barrier is formed of a phosphor paste containing glass frit, and each discharge space is formed by an independent cell barrier. 2. The plasma display panel according to claim 1, wherein a plurality of cell barriers constituting one pixel for color display are patterned using phosphors of red, green and blue. 3. A method of manufacturing a plasma display panel according to claim 1, wherein a step of forming a female mold corresponding to the region of the cell barrier on the substrate, and a glass frit in the space of the female mold. A method of manufacturing a plasma display panel, comprising: a step of filling a phosphor paste contained therein; and a step of forming a cell barrier of the phosphor by eliminating the female mold. 4. The step of forming the female mold comprises the steps of providing a photoresist layer on a substrate and performing pattern exposure and development on the photoresist layer. A method for manufacturing the plasma display panel described. 5. The method for manufacturing a plasma display panel according to claim 1, wherein a step of forming a female mold on a substrate corresponding to a region including a cell barrier and a discharge space, and the female mold of the female mold. A step of filling a phosphor paste containing a glass frit in the space, a step of forming a discharge space by performing a sandblasting process through a sandblasting mask provided with a window corresponding to the discharge space, And a step of forming a cell barrier made of a phosphor by eliminating the female mold. 6. The step of forming the female mold comprises the steps of providing a photoresist layer on a substrate and performing pattern exposure and development on the photoresist layer. A method for manufacturing the plasma display panel described. 7. The step of forming the sandblasting mask comprises a step of providing a photoresist layer on the female mold, and a step of performing pattern exposure and development on the photoresist layer. A method for manufacturing a plasma display panel according to claim 5.