JP2011222325A - Method for manufacturing plasma display panel, and plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a PDP that operates at a high luminous efficiency and whose color reproduction capability is sufficient.SOLUTION: A sealing glass layer 40 is formed on the periphery of a surface opposed to a back panel plate 20. In a center part A in the lengthwise direction of the back panel plate 20, the height H1 of the sealing glass layer 40 is equal to or greater than the height of a partition 24 and is equal to or smaller than a value that is ten times larger than the height of the partition 24. A height H2 at both edges B in the lengthwise direction of the sealing glass layer 40 exceeds the height H1 and is equal to or smaller than the value that is ten times larger than the height H1. A front panel plate 10 and a back panel plate 20 are disposed to face each other and fixed by pressing by a clip so that an inner space is formed inside the sealing glass layer 40 and the partition 24 is sandwiched. In this state, sealing is performed by heating the sealing glass layer to a temperature equal to or higher than the softening temperature thereof.

Description

  The present invention relates to a plasma display panel (hereinafter also referred to as PDP) and a manufacturing method thereof.

  PDP is broadly divided into AC type and DC type in terms of driving, and there are two types of discharge types, surface discharge type and counter discharge type. However, due to high definition, large screen, and ease of manufacturing, At present, the surface discharge type with a three-electrode structure is the mainstream.

  This surface discharge type PDP has a structure in which a front substrate and a rear substrate, which are a pair of substrates transparent at least on the front side, are arranged to face each other so that a discharge space is formed between the substrates, and a plurality of the discharge spaces are formed. A partition wall for partitioning is disposed on at least one of the substrates, and a display electrode is provided on the front substrate and an address electrode is provided on the rear substrate so that discharge is generated in the discharge space partitioned by the partition wall. A plurality of discharge cells are formed by providing phosphors that emit red, green, and blue light that are emitted by discharge, and the phosphors are excited by vacuum ultraviolet light having a short wavelength that is generated by discharge. Color display is performed by emitting red, green, and blue visible light from the blue discharge cells, respectively.

The front substrate includes a dielectric layer and a protective layer on the dielectric layer so as to cover the display electrodes.
Such a PDP is capable of high-speed display compared to a liquid crystal panel, has a wide viewing angle, is easy to increase in size, and is self-luminous, so that the display quality is high. Recently, it has attracted particular attention among panel displays, and is used for various purposes as a display device in a place where many people gather or a display device for enjoying a large screen image at home (see Patent Document 1). ).

By the way, the PDP having the above-described structure is manufactured as follows.
That is, first, a display electrode is formed by applying and baking a silver paste on a front substrate, a dielectric glass paste is applied and baked thereon to form a dielectric layer, and a protective layer is further formed thereon. .

On the back substrate, silver paste is applied and baked to form address electrodes, and glass paste is applied at a predetermined pitch and baked to form partition walls.
Then, each color phosphor paste is applied between the barrier ribs and fired at about 500 ° C. to remove the resin component and the like in the paste, thereby forming a phosphor layer.
Then, the front substrate and the rear substrate obtained by the above steps are coated with a glass frit for sealing on the outer periphery, and calcined at about 350 ° C. to remove the resin component and the like to form a sealing glass layer. (Frit calcining process).

  Thereafter, the front substrate and the rear substrate are stacked so that the display electrodes and the address electrodes are opposed to each other, and in this state, heated to a temperature (about 450 ° C.) higher than the softening temperature of the sealing glass. To seal (heat sealing process).

Then, while heating the sealed panel to about 350 ° C., an internal space formed between the two substrates (a space formed between the front glass substrate and the rear glass substrate surrounded by the sealing glass layer, The phosphor layer is exposed) (exhaust process), and after the exhaust is completed, the discharge gas is introduced to a predetermined pressure (usually 4 to 7 × 10 ⁴ Pa).

JP 2003-131580 A

In the PDP manufactured as described above, further improvement in luminance and color reproducibility is desired.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a PDP that operates with high luminous efficiency and has good color reproducibility.

  In order to achieve the above object, the PDP manufacturing method of the present invention includes a sealing layer forming step of forming a sealing glass layer on at least one outer peripheral portion of the opposing surface of the front substrate and the rear substrate, and then the front surface. A pressing step in which the substrate and the back substrate are overlapped so as to sandwich the partition so that an internal space is formed inside the sealing glass layer and pressed with a clip, and the softening temperature of the sealing glass layer in that state A heat sealing step for sealing by heating to the above, and the height of the sealing glass layer formed in the sealing layer forming step is set to a partition wall in the longitudinal center portion of the front substrate and the rear substrate. Is equal to or higher than the height of the partition wall and not more than 10 times the height of the partition wall, and exceeds the height of the sealing glass layer in the central portion at both ends in the longitudinal direction of the front substrate and the rear substrate, and seals in the central portion. Less than 10 times the height of the glass layer It, from the central portion as toward the end portions, the height was made to increase.

  A PDP according to the present invention includes a front substrate and a rear substrate that are opposed to each other with a partition wall interposed therebetween so as to form a discharge space inside a heat-sealed sealing glass layer, and a discharge gap is sandwiched between the front substrate and the front substrate. A display electrode composed of a scan electrode and a sustain electrode facing each other, a dielectric layer covering the display electrode, and a protective layer covering the dielectric layer, and having an address electrode intersecting the display electrode on the back substrate And the width | variety of the sealing glass layer along a panel longitudinal direction increases so that it goes to both ends from the center part of a panel longitudinal direction, and it is formed so that the width | variety of both ends may become wider than a center part.

  According to the present invention, the impurity gas is released to the outside through the gap formed between the sealing glass layer and the substrate in the heat sealing step. Therefore, performance degradation due to the impurity gas can be suppressed, so that a PDP that operates with high luminous efficiency and good color reproducibility can be provided.

It is a principal part cross-section perspective view which shows schematic structure of PDP manufactured by the manufacturing method of PDP by one embodiment of this invention. It is an electrode array diagram of PDP manufactured by the manufacturing method of PDP by one embodiment of the present invention. It is a figure which shows an example of a specific form at the time of forming the sealing glass layer in the manufacturing method of PDP by one embodiment of this invention. It is a figure which shows typically the sealing part in PDP manufactured by the manufacturing method of PDP by one embodiment of this invention.

Hereinafter, although the manufacturing method of PDP by one Embodiment of this invention is demonstrated using figures, the aspect of this invention is not limited to this.
First, the structure of a PDP manufactured by a method for manufacturing a PDP according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a main part of a PDP according to an embodiment. In FIG. 1, a display region in the central part of the PDP is partially shown.
This PDP has a front panel plate 10 in which display electrodes 12 (scanning electrodes 12 a and sustaining electrodes 12 b), a dielectric layer 13, and a protective layer 14 are arranged on a front substrate 11, and an address electrode 22 on a rear glass substrate 21. The rear panel plate 20 on which the dielectric layer 23 is disposed is configured to be spaced apart from each other in parallel with the display electrode 12 and the address electrode 22 facing each other.
The gap between the front panel plate 10 and the rear panel plate 20 is partitioned by, for example, striped partition walls 24 to form a discharge space 30, and a discharge gas is enclosed in the discharge space 30.

Further, in the discharge space 30, a phosphor layer 25 is disposed on the back panel plate 20 side. The phosphor layer 25 is repeatedly arranged in the order of red, green, and blue.
The display electrode 12 and the address electrode 22 are both striped, the display electrode 12 is arranged in a direction orthogonal to the partition wall 24, and the address electrode 22 is arranged in parallel to the partition wall 24. A cell that emits red, green, and blue light is formed where the display electrode 12 and the address electrode 22 intersect.

  Here, the shape of the display electrode 12 is a stripe shape. However, for example, an island-shaped electrode or an electrode in which a hole is formed can be used. Further, the partition wall 24 may not be formed in a stripe shape, and may be implemented, for example, in a cross beam shape.

The address electrode 22 is a metal electrode (for example, a silver electrode or a Cr—Cu—Cr electrode).
The display electrode 12 has an electrode configuration in which a thin bus electrode (silver electrode, Cr—Cu—Cr electrode) is laminated on a wide transparent electrode made of a conductive metal oxide such as ITO, SnO ₂ , or ZnO. Although it is preferable to secure a wide discharge area, a metal electrode can be used in the same manner as the address electrode 22.

The dielectric layer 13 is a layer made of a dielectric material disposed so as to cover the entire surface of the front glass substrate 11 on which the display electrodes 12 are arranged. The protective layer 14 is a thin layer made of, for example, magnesium oxide (MgO). Thus, the surface of the dielectric layer 13 is covered.

The dielectric layer 23 is the same as the dielectric layer 13, but TiO ₂ particles may be mixed so as to also serve as a visible light reflecting layer.
The partition walls 24 are made of a glass material, and are projected on the surface of the dielectric layer 23 of the back panel plate 20 at a constant pitch.

Here, as the phosphor material constituting the phosphor layer 25, for example, blue phosphor: BaMgAl ₁₀ O ₁₇ : Eu, green phosphor: Zn ₂ SiO ₄ : Mn, red phosphor: (Y _X Gd _{1- X 2} ) BO ₃ : Eu.

In the case of a 40-inch class high-vision PDP, the dielectric layer 13 has a thickness of about 20 μm, and the protective layer 14 has a thickness of about 0.5 μm. The height of the partition wall 24 is 0.1 to 0.15 mm, the partition wall pitch is 0.15 to 0.3 mm, and the thickness of the phosphor layer 25 is 5 to 50 μm. The discharge gas to be sealed is Ne—Xe, the Xe content is 5% by volume, and the sealing pressure is set in the range of 500 to 800 Torr (6.5 to 10.4 × 10 ⁴ Pa).

  When this PDP is driven, wall charges are accumulated in the cells to be caused to emit light by applying address discharge pulses to the scan electrodes 12a and the address electrodes 22 by a drive circuit (not shown), and then the display electrodes. Light emission display is performed by repeating the operation of applying a sustain discharge pulse between the pair 12 to perform a sustain discharge in a cell in which wall charges are accumulated.

  At the time of driving the PDP, as shown in FIG. 2, each driver and the panel driving circuit 100 are connected to the PDP, and an address discharge pulse is applied between the scan electrode 12a and the address electrode 22 of the cell to be lit. After discharging and accumulating wall charges in the cell to emit light, a sustain voltage is applied by applying a pulse voltage between the display electrode pair 12. The cell in which the wall charges are accumulated emits ultraviolet light along with the discharge, and is converted into visible light by the phosphor layer 25. Such an operation of lighting the cell is repeated to display an image.

[PDP production method]
A method for manufacturing the PDP having the above configuration will be described below.
[Preparation of front panel plate]
A display electrode 12 is formed on the front glass substrate 11 by applying a silver electrode paste by screen printing and then firing, and a paste containing a glass material is applied by screen printing so as to cover the display electrode 12 and fired. Thus, the dielectric layer 13 is formed. Further, the front panel 10 is produced by forming a protective layer 14 made of magnesium oxide (MgO) on the surface of the dielectric layer 13 by vacuum deposition or the like.

[Preparation of rear panel plate]
An address electrode 22 is formed on the back glass substrate 21 by screen printing a silver electrode paste and then firing, and a paste containing a glass material is applied and fired thereon by a screen printing method. The body layer 23 is formed, and a paste containing the glass material is repeatedly applied at a predetermined pitch using a screen printing method, and then fired to form the partition wall 24.

  Then, red, green, and blue phosphor pastes are prepared, and the paste is scanned in the gaps between the partition walls 24, for example, by screen printing or by ejecting phosphor ink from the nozzles, or phosphors of each color. A method of producing a photosensitive resin sheet containing the material, attaching the sheet to the surface of the rear glass substrate 21 on which the partition wall 24 is disposed, patterning by photolithography, and developing to remove unnecessary portions, etc. The back panel board 20 is manufactured by forming each color phosphor layer 25 by applying the film and then baking in air.

[Seal of front panel plate and rear panel plate, evacuation, discharge gas sealing]
The front panel plate 10 and the back panel plate 20 thus manufactured are overlapped and sealed via a sealing glass layer, evacuated, and then filled with a discharge gas to manufacture a PDP.

Below, the process of superimposing and sealing the front panel board 10 and the back panel board 20 is demonstrated in detail.
Sealing glass layer forming process:
A glass frit paste for sealing is applied to the outer peripheral portion of one or both of the front panel plate 10 and the rear panel plate 20 produced as described above, and this is used to remove the resin component contained in the paste. A sealed glass layer is obtained by calcination.

  FIG. 3 shows a specific form when the sealing glass layer 40 is formed by applying a sealing glass frit paste on the back glass substrate 21 and calcining in the sealing glass layer forming step. It is a figure which shows an example.

  3A is a top view of the back panel plate 20, and FIG. 3B is a side view of the back panel plate 20. FIG. In the example shown in FIG. 3, a sealing glass layer 40 is provided on the outer peripheral portion of the surface of the back panel plate 20.

  The height of the sealing glass layer 40 before being sandwiched between the clips is not uniform over the entire circumference. In the central portion A in the longitudinal direction of the back panel plate 20, the height H1 is equal to the height of the partition wall 24. At both end portions B in the longitudinal direction, there is a gap between the partition wall 24 when the front panel plate 10 and the rear panel plate 20 are overlapped and pressed with a clip in the next heat sealing step. In addition, the height H2 is set so as to be crushed by the pressing force of the clip and come into contact with the partition wall when the sealing is completed.

  Therefore, in the central portion A in the longitudinal direction of the back panel plate 20, the height H 1 of the sealing glass layer 40 is equal to or higher than the height h of the partition wall 24 and not more than 10 times the height of the partition wall 24. (H ≦ H1 ≦ 10h). The “center portion A” may be in the range of about 25% of the length in the longitudinal direction from the center in the longitudinal direction of the back panel plate 20. That is, the height H1 of the sealing glass layer 40 is equal to or more than the height h of the partition wall 24 and 10 times in a part or all of the range from about the middle in the longitudinal direction to about 25% of the length in the longitudinal direction. The following.

  On the other hand, the height H2 of the sealing glass layer 40 at both ends B in the longitudinal direction exceeds the height H1 and is not more than 10 times the height H1 (H1 <H2 <10H1). Preferably, the height H2 is not less than 1.5 times the height H1.

And the height of the sealing glass layer 40 is increasing toward the both ends B from the center part A, as shown in FIG.3 (b).
As a method for applying a sealing glass frit paste on the back panel plate 20, a commonly used dispenser can be used. In order to form the sealing glass layer 40 in the above shape by this method, when applying by scanning the dispenser while discharging the paste, the speed at which the dispenser is scanned, the distance between the dispenser and the substrate 20, and This can be realized by controlling the discharge amount from the dispenser.

In addition to the dispenser method, the sealing glass layer 40 can be formed in the shape as described above by performing overcoating using a screen printing method.
Heat sealing process:
Thereafter, the front panel plate 10 and the rear panel plate 20 are overlapped so that the display electrodes 12 and the address electrodes 22 cross and face each other, and the stacked panel plates 10 and 20 are pressed and fixed with clips, In a fixed state, the sealing glass layer 40 is softened by heating and then sealed by cooling.

  As a result, the sealing layer 50 is formed on the outer peripheral portion between the front panel plate 10 and the rear panel plate 20, and the internal space (the space between the panel plates 10 and 20 surrounded by the sealing layer 50) is , Shut off from the external space and sealed.

  As described above, the sealing glass layer 40 is formed such that the height of the sealing glass layer 40 is increased from the central portion A in the longitudinal direction of the panel toward both end portions B. Therefore, the sealing glass layer 40 is formed by being softened. As shown in FIG. 5A, the width of the adhesive layer 50 increases from the central portion A in the longitudinal direction of the panel toward both end portions B, and the width at the both end portions B is wider than the central portion A. Formed to be.

[Effects of the above PDP manufacturing method]
According to the manufacturing method, the height of the sealing glass layer 40 formed on the back panel plate 20 in the sealing glass layer forming step prior to the heat sealing step is equal to or higher than the height h of the partition wall 24 as described above. Since it is set and increases from the central portion A toward both end portions B, it is relatively sealed when the front panel plate 10 is overlapped on the back panel plate 20 and sandwiched by clips in the heat sealing step. In the central portion A where the height of the glass layer 40 is low, the front panel plate 10 comes into contact with the top of the partition wall 24 and an appropriate contact resistance is generated. Accordingly, the front panel plate 10 and the rear panel plate 20 are stably positioned during alignment, and the superimposed positions are not easily displaced.

Further, at both ends B, a gap is formed between the front plate 10 and the top of the partition wall 24, and the gap increases as the both ends B are approached.
Therefore, when the sealing glass layer 40 is softened by heating and sealing in the heat sealing step, gas such as water vapor is usually adsorbed on the front panel plate 10 and the back panel plate 20. The adsorbed gas is released, but the presence of the gap as described above makes it easy to ventilate the discharge space during the period until the sealing is completed, and thus the impure gas inside the PDP after sealing. It is possible to greatly reduce the residual amount.

  As a result, in the protective layer 14 and the phosphor layer 25, the deterioration of the material properties considered to be caused by the impure gas is reduced, so that it is possible to provide a PDP that operates with high luminous efficiency and good color reproducibility. .

  Further, when the sealing is completed, the sealing glass layer 40 is crushed by the pressing force of the clip, and the front panel plate 10 and the top of the partition wall 24 come into full contact. The gap between the front panel plate 10 and the rear panel plate 20 is substantially equal to the height h of the partition wall. The internal space and the outside of the panel are well sealed by the sealing layer 50.

  Note that the effect of reducing the impure gas is improved as the heights H1 and H2 of the sealing glass layer 40 are set larger than the height h of the partition wall 24. However, if the height H1 is too large, When sandwiched, the front panel plate 10 is less likely to come into contact with the partition wall 24 in the central portion A, so that it is difficult to obtain a positioning stability effect. If the heights H1 and H2 are too large, it becomes difficult for the front panel plate 10 and the top of the partition wall 24 to come into full contact with each other when sealing is completed, and the positioning stability effect of the front panel plate 10 and the rear panel plate 20 is also reduced. Since the width of the sealing layer 50 is also increased, the heights H1 and H2 are 10 times or less the height h of the partition wall and the height H2 is as described above in consideration of these points. It is preferable to set it to 10 times or less of the height H1.

  As shown in the sealing layer 50 shown in FIG. 4, the width increases from the center A in the longitudinal direction of the panel toward both ends B, and the width at both ends B is wider than the center A. The PDP having the characteristics described above can be estimated to have been manufactured by the above-described manufacturing method. Therefore, it can be estimated that the PDP operates with high luminous efficiency and has good color reproducibility.

[Variations etc.]
In the said embodiment, although the sealing glass layer 40 was formed in the back panel board 20, even if it forms the sealing glass layer in the front panel board 10, it can implement similarly. Moreover, even if it forms a sealing glass layer in both the front panel board 10 and the back panel board 20, it can implement.

Moreover, in the said embodiment, although the partition 24 was formed in the back panel board 20, a partition may be formed in the front panel board 10, and it can implement similarly.
Moreover, even if a partition is formed in both the front panel board 10 and the back panel board 20, it can implement similarly.

  As described above, according to the present invention, it is possible to realize a PDP that operates with high luminous efficiency and has good color reproducibility. In particular, the present invention is useful in a large-screen, high-definition PDP.

DESCRIPTION OF SYMBOLS 10 Front panel board 20 Back panel board 21 Back glass board 24 Partition 40 Sealing glass layer 50 Sealing layer

Claims (2)

A sealing layer forming step of forming a sealing glass layer on at least one outer peripheral portion of the opposing surface of the front substrate and the rear substrate, and then, the inner space is formed inside the sealing glass layer of the front substrate and the rear substrate. And a pressing step in which the partition walls are sandwiched and pressed and fixed with a clip, and a heating and sealing step in which sealing is performed by heating the sealing glass layer to a temperature higher than the softening temperature in that state. A method for manufacturing a plasma display panel, comprising:
The height of the sealing glass layer formed in the sealing layer forming step is as follows:
In the central portion in the longitudinal direction of the panel, the height is equal to or higher than the height of the partition wall and not more than 10 times the height of the partition wall. A method for manufacturing a plasma display panel, which is more than 10 times the height of the sealing glass layer in the central portion and increases in height from the central portion toward the both end portions. A scanning electrode opposed to the front substrate with a discharge gap on the front substrate, the front substrate and the rear substrate being opposed to each other so as to form a discharge space inside the heat-sealed sealing glass layer; A plasma display having a display electrode constituted by a sustain electrode, a dielectric layer covering the display electrode, and a protective layer covering the dielectric layer, and having an address electrode intersecting the display electrode on the back substrate In the panel,
The width of the sealing glass layer along the longitudinal direction of the panel is
A plasma display panel formed so as to increase from the central portion in the longitudinal direction of the outer peripheral portion of the panel toward both end portions, and to be wider at both end portions than the central portion.

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