JP2002231140A - Aging method and production method for plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a PDP from being cracked and uniform the panel characteristics in a display part by reducing a variation in surface temperature of the PDP while aging is performed. SOLUTION: A heat conductive anisotropic sheet 102 having a thermal conductivity larger in surface direction than in thickness direction is installed on the chassis 100 of an aging device, the plasma display panel 1 is placed on a heat conductive anisotropic sheet 102 and, with a heat conductive anisotropic sheet 104 having a heat conductivity larger in surface direction than in thickness direction placed on the front glass substrate 1b of the plasma display panel so as to cross the boundary of the display part and the non-display part of the plasma display panel, all discharge cells in the display part of the plasma display panel are lit to perform aging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of aging a plasma display panel constituting a plasma display device used as a television or the like and a method of manufacturing the same.

[0002]

2. Description of the Related Art A plasma display device is a display device excellent in visibility characterized by being thin and light. With respect to this plasma display device, developments mainly aimed at large screen and high definition have been promoted.

A plasma display device includes a plasma display panel for displaying an image, a control circuit, a chassis, a frame, and the like. In a plasma display device, a plasma display panel (hereinafter sometimes referred to as a PDP) is an element that can be called a main body that displays an image.

Displaying a color image on a PDP is performed by generating a discharge in a discharge cell to generate an ultraviolet ray, and irradiating the fluorescent substance with the ultraviolet ray. The phosphor is colored red, green, and blue for each discharge cell, and one pixel is composed of three cells. The color of the pixel is made desired by adjusting the light emission of each discharge cell.

A PDP is driven by an AC (alternating current) depending on a driving method.
Type and DC (direct current) type. The AC type is further divided into two types, a surface discharge type and a counter discharge type, depending on the discharge type. At present, AC type surface discharge type PDP
Is mainly adopted. This is because the AC surface discharge type PDP is suitable for high definition and large screen, and the manufacturing is simple.

[0006] AC surface-discharge PDPs typically have a front glass substrate, a back glass substrate, and barriers arranged to form a number of cells between the two glass substrates. Electrodes corresponding to each cell are formed on opposing surfaces of each glass substrate. A plurality of stripe-shaped display electrodes are formed on the front glass substrate. One display electrode is composed of a combination of one scan electrode and one sustain electrode.
A plurality of striped data electrodes are formed on the rear glass substrate. In a PDP, a front glass substrate and a rear glass substrate are integrated such that display electrodes and data electrodes face each other and are orthogonal to each other.

[0007] The barrier secures an appropriate discharge gap by regulating the distance between the two glass substrates, and prevents crosstalk to adjacent cells. Generally, the barrier of the AC type color PDP is formed in a stripe shape. A phosphor layer of any one of red (R), green (G), and B (blue) is formed in one partition.
Further, an inert gas is sealed in the barrier. The inert gas generates ultraviolet light when a discharge is generated in the cell.

The AC surface discharge type PDP is manufactured as follows. First, various projections serving as electrodes and partition walls are formed on a glass substrate, and a front substrate and a rear substrate are manufactured. Next, the surroundings are sealed by facing the two substrates,
An inert gas is sealed therein. The PDP thus assembled is then aged.

Generally, the light emission characteristics and discharge characteristics of a PDP that has been assembled are unstable in the initial stage of lighting. In addition, a high voltage is required to light the assembled PDP. Aging is performed to stabilize the light emission characteristics and discharge characteristics of the PDP and to lower the driving voltage. Aging is performed by lighting all the discharge cells of the display unit of the PDP that has been assembled for a predetermined time. Generally, a discharge is generated by applying a voltage to a display electrode provided on a front glass substrate of a PDP.

After the aging, the PDP is connected to a control circuit, and attached to a chassis together with other necessary parts. Finally, the frame is attached to obtain a plasma display device as a final product.

[0011]

Aging is in PDP.
Is the first step of lighting, and therefore, is performed by applying a voltage higher than the drive voltage. Therefore, the temperature of the PDP increases during the aging. When the temperature of the PDP increases, cracking of the PDP may occur. P
DP cracking occurs when the in-plane temperature of the PDP is not uniform. Generally, when a temperature difference of 20 ° C. or more occurs at 2 cm on the PDP surface, the PDP tends to crack.
A temperature difference of 20 ° C. or more at 2 cm means that the temperature at a certain point on the surface of the PDP panel is 2
It means that the difference from the temperature at a point separated by cm is 20 ° C. or more.

The temperature difference generated on the PDP surface is particularly likely to occur between the display part and the non-display part. This is because the non-display portion is a region that does not include a discharge cell, does not generate discharge during aging, and its temperature does not rise as high as the display portion.

[0013] The non-uniform in-plane temperature of the PDP during aging is also considered to be a cause of variations in panel characteristics after aging. Specifically, variations in panel characteristics appear as color unevenness when an image is displayed by incorporating a PDP into a plasma display device.

In view of these problems, in a general aging apparatus, a sheet made of silicone rubber (for example, product number 9829FR manufactured by Sumitomo 3M Limited) is mounted on the surface of an aluminum chassis (or table) on which a PDP is mounted. A heat conductive sheet and an aluminum foil are laid in this order, and the PDP is placed in contact with the aluminum foil. The heat conductive sheet serves to equalize the in-plane temperature of the PDP during aging, and the aluminum foil serves to equalize the charge on the chassis surface and prevent the heat conductive sheet from adhering to the panel. Play a role.

Further, during aging, the upper surface of the PDP is cooled by a fan provided above the PDP. The cooling by the fan is performed in order to promote the cooling of the PDP and make the in-plane temperature uniform.

As described above, by employing the heat conductive sheet and the cooling fan, the variation in the in-plane temperature during aging is reduced, and a PDP having no practical problem at present is obtained. However, even in the current aging process, the in-plane temperature variation of the PDP still exists. For example, a PDP located directly below a cooling fan
Has been found to be about 5 to 10 ° C. lower than the temperature of the PDP at other positions. If such a temperature difference is eliminated, it is considered that a PDP with more uniform panel characteristics can be obtained. Further, it is expected that a shortening of the aging time will be required in order to increase the production efficiency in the future, and in such a case, it is necessary to generate a discharge by applying a higher voltage. The higher the voltage, the higher the temperature of the PDP and the greater the in-plane temperature variation. In that case, the current aging method cannot prevent the PDP from cracking, and the dispersion of panel characteristics may increase.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and reduces the variation in the in-plane temperature of a PDP during aging, thereby preventing cracking of the PDP and improving the panel characteristics after aging. To make the more uniform
A method for aging DP and a method for manufacturing the same are provided.

[0018]

According to a first aspect of the present invention, there is provided a plasma display panel aging method for lighting all discharge cells of a display section of a plasma display panel.
A thermally conductive anisotropic sheet having a relatively larger thermal conductivity in the plane direction than the thickness direction is disposed between the chassis on which the plasma display panel is mounted and the back glass substrate of the plasma display panel, and aging is performed. An aging method for a plasma display panel is provided.

The aging method of the PDP is such that the aging device is provided between the chassis and the back glass substrate of the PDP.
Aging is performed in a state where a heat conductive anisotropic sheet having a relatively large heat conductivity in a plane direction with respect to a thickness direction is interposed. The heat transmitted to the heat conductive anisotropic sheet is mainly conducted in the plane direction. Therefore, even if the amount of heat generated on the surface of the PDP mounted thereon varies, the heat is conducted in the plane direction by the heat conductive anisotropic sheet and is made uniform. As a result, aging can be performed in a state in which the variation in the in-plane temperature of the PDP is further reduced. By further reducing the variation of the in-plane temperature during aging, cracking of the PDP is further prevented and the panel characteristics of the PDP become more uniform. Therefore, if the invention according to the first gist is used,
Aging can be completed in a short time by increasing the voltage.

In the invention according to the first aspect, the heat conductive anisotropic sheet preferably has a ratio of the heat conductivity in the plane direction to the heat conductivity in the thickness direction in the range of 120: 1 to 160: 1. Some are used. As such a thermally conductive sheet, a graphite sheet is preferably used.

According to a second aspect of the present invention, there is provided a plasma display panel aging method for lighting all discharge cells of a display section of a plasma display panel, the method comprising: A display in which aging is performed by placing a thermally conductive anisotropic sheet having a relatively large thermal conductivity on a front glass substrate of a plasma display panel so as to straddle a boundary between a display portion and a non-display portion of the plasma display panel A method for aging a panel is provided.

This aging method is characterized in that aging is performed in a PDP panel by reducing a temperature difference between a display portion and a non-display portion. When a thermally conductive anisotropic sheet is placed on a PDP so as to straddle the boundary between the display part and the non-display part, heat is transferred from the hot display part to the low-temperature non-display part via the heat conductive anisotropic sheet. It is easily conducted. As a result, the temperature difference between the display unit and the non-display unit can be reduced,
Cracking of the PDP near the boundary between the two is further prevented. That is, according to the second aspect of the present invention, the temperature difference can be quickly reduced even under the condition that the temperature difference between the display unit and the non-display unit is large. Therefore, the second
By using the present invention according to the gist, it is possible to end the aging in a short time by increasing the voltage.

In the invention according to the second aspect, the heat conductive anisotropic sheet preferably has a ratio of the heat conductivity in the plane direction to the heat conductivity in the thickness direction of 120: 1 to 160: 1. Is used. As such a thermally conductive sheet, a graphite sheet is preferably used.

According to a third aspect, the present invention is a method of aging a plasma display panel for lighting all discharge cells of a display section of the plasma display panel, the heat conduction being relatively larger in a plane direction than in a thickness direction. A heat conductive anisotropic sheet having a thermal conductivity between the chassis on which the plasma display panel is mounted and the back glass substrate of the plasma display panel, and having a relatively higher thermal conductivity in the plane direction than in the thickness direction. An aging method for a plasma display panel is provided, in which the heat conduction anisotropic sheet is mounted on a front glass substrate of the plasma display panel so as to straddle a boundary between a display portion and a non-display portion of the plasma display panel and aging is performed.

This aging method includes the aging method of the PDP according to the first aspect and the PDP according to the second aspect.
The aging method is a combination of the aging method described above. According to this aging method, the in-plane temperature of the PDP becomes more uniform during aging, the panel characteristics after aging become uniform, and the temperature difference between the display unit and the non-display unit. Is smaller, and the PDP is prevented from cracking near the boundary between the two.

The present invention also provides a method for producing a PDP including any one of the aging methods of the present invention. By using the aging method of the present invention, aging can be completed in a short time by applying a higher voltage. Therefore, the method for producing a PDP of the present invention enables production of a PDP with higher production efficiency.

[0027]

Embodiments of the present invention will be described below. The aging method for a PDP according to the first aspect of the present invention has a relatively large thermal conductivity in a plane direction with respect to a thickness direction between a chassis on which the PDP is mounted and a rear glass substrate of the PDP. By arranging a heat conductive anisotropic sheet,
It is characterized by aging DP.

The chassis is a table on which the PDP is mounted. The chassis may be one commonly used in an aging device. The chassis is typically made of aluminum.

It is preferable that the heat conductive anisotropic sheet is laid beforehand on the surface of the chassis before the PDP is placed.
The heat conductive anisotropic sheet may be fixed to the chassis using, for example, a double-sided tape. If the heat conductive anisotropic sheet is fixed to the chassis, it is possible to prevent the heat conductive anisotropic sheet from shifting when the PDP is placed before aging and / or when the PDP is taken out after aging.

The thermally conductive anisotropic sheet having a relatively large thermal conductivity in the plane direction with respect to the thickness direction is preferably a graphite sheet. The graphite sheet has a thermal conductivity in the plane direction of 700 W / (m · K) to 800 W / (m).
-It is preferable that it is in the range of K). Further, the graphite sheet preferably has a thickness of 2 mm or more. Since the graphite sheet is brittle, if its thickness is small, the durability is poor. If a graphite sheet having low durability is used, it may be necessary to frequently replace the graphite sheet, and the production efficiency of PDP may be reduced.

The graphite sheet that can be used in the aging method of the present invention is described in, for example, JP-A-3-75211.
And described in JP-A-2000-169125, and can be produced according to the method described in the publication. The contents described in these publications are incorporated herein by reference.

In order to protect the surface of the graphite sheet, for example, an aluminum foil may be laid on the surface of the graphite sheet as a protective sheet. If the thickness of the protective sheet is large, the effect of the graphite sheet to make the in-plane temperature of the PDP uniform may not be sufficiently obtained. When an aluminum foil is used as the protective sheet, its thickness is preferably 10 to 50 μm.

The aging method for a PDP according to the second aspect of the present invention is characterized in that a front glass substrate of the PDP is provided so as to straddle a boundary between a display section and a non-display section in a plane direction relative to a thickness direction. Aging is performed by mounting a heat conductive anisotropic sheet having a large heat conductivity.

In this aging method, the heat conductive anisotropic sheet has a function of transferring heat from a high-temperature display section to a low-temperature non-display section to reduce the temperature difference between the two. Therefore, the heat conductive anisotropic sheet is disposed so as to cover a region including a boundary between the display unit and the non-display unit.

The heat conductive anisotropic sheet is formed such that the PDP is covered with the heat conductive anisotropic sheet so that both the display part and the non-display part are covered by 1 to 2 cm from the boundary between the display part and the non-display part.
Is preferably placed on the front glass substrate. That is, FIG.
As shown in the figure, the width W1 of the display unit covered with the heat conductive anisotropic sheet (104) is 1 near the boundary between the display unit and the non-display unit of the PDP (1) (indicated by a dashed line in the figure). It is preferable that the width W2 of the non-display portion covered with the heat conductive anisotropic sheet (104) is 1 to 2 cm. W1 and W2
May be the same or different. W1
May not be constant in one PDP, and may be partially wide or narrow. The same applies to W2.

When the PDP is rectangular (including a square), the display portion is rectangular, and the non-display portion has a frame-like shape surrounding the display area, the heat conductive anisotropic sheet is preferably 2
It has a frame shape having a width of about 4 cm, and is arranged such that its center line overlaps the boundary between the display unit and the non-display unit. Or,
A band-like thermally conductive anisotropic sheet having a width of 2 to 4 cm may be arranged on the four sides of the PDP such that the center line overlaps the boundary between the display unit and the non-display unit.

The thermally conductive anisotropic sheet preferably used in the invention according to the second aspect is a graphite sheet. The graphite sheet preferably used in the invention according to the second aspect is the same as the graphite sheet described above with respect to the invention according to the first aspect.

The heat conduction anisotropic sheet straddling the boundary between the display part and the non-display part may be arranged on the front glass substrate plate of the PDP after the PDP is mounted on the chassis of the aging device.
Alternatively, the PDP may be placed on the chassis of the aging device after the heat conduction anisotropic sheet is arranged on the front glass substrate of the PDP so as to straddle the boundary between the display unit and the non-display unit. The heat conductive anisotropic sheet straddling the boundary between the display unit and the non-display unit may be fixed to the PDP as needed.

The PDP aging method according to the third aspect of the present invention is a combination of the PDP aging method according to the first aspect of the present invention and the PDP aging method according to the second aspect. . PD according to the third point
The aging method of P is schematically shown in FIGS.

FIG. 1 shows a PD in the aging device chassis.
A state in which the aging method of the present invention is carried out with P placed thereon is schematically shown in a sectional view. The PDP is mounted on the chassis such that the rear glass substrate (1a) faces the chassis (100). Back glass substrate of PDP (1a)
A heat conductive anisotropic sheet (preferably a graphite sheet) (102) laid on the chassis (100) is disposed between the chassis and the chassis (100). On the front glass substrate (1b) of the PDP, a frame-like heat conductive anisotropic sheet (preferably a graphite sheet) is formed so as to straddle the boundary between the display part and the non-display part (indicated by a dashed line in the figure). )(Ten
4) is placed.

FIG. 2 is a plan view schematically showing a state in which the PDP (1) is mounted on the chassis of the aging device. The frame-shaped heat conductive anisotropic sheet (104) has a width of 3 cm, and its center line overlaps the boundary between the display part and the non-display part (indicated by a dashed line in the figure). Therefore, the widths W1 and W2 in which the display portion and the non-display portion are covered with the heat conductive anisotropic sheet (104) are each 1.5 cm.

In the illustrated embodiment, the heat conductive anisotropic sheet laid on the chassis is the same as the heat conductive anisotropic sheet disposed on the front glass substrate of the PDP. If necessary, both may be selected so that at least one selected from, for example, a material, thermal conductivity, and thickness is different from each other.

The aging method of the PDP of the present invention can be carried out using a conventional apparatus and method except that a heat conductive anisotropic sheet is used. For example, A
When aging a C-plane discharge type PDP, aging is performed by connecting a terminal of a power supply of the aging device to a display electrode provided on a front glass substrate. Aging is PD
The voltage selected according to the type of P is several hours to several tens of hours,
It is performed by applying the voltage continuously. In order to make the in-plane temperature of the PDP more uniform during aging, the PDP
May be operated to cool the front glass substrate of the PDP. The size and number of fans are selected according to the size of the PDP. For example, P
If the DP is a 42-inch type, it is preferable to arrange 12 fans in 3 rows × 4 columns so that the entire surface of the PDP is cooled.

The PDP aging method of the present invention can be applied to any type of PDP, for example, an AC facing discharge type PDP and a DC type PDP.

The PDP aged by the aging method of the present invention constitutes a plasma display device together with a control circuit, an aluminum chassis and a frame. The plasma display device can be assembled according to a conventional method.

[0046]

According to the first aspect of the present invention, there is provided a method for aging a PDP according to the present invention, wherein a relative position between a chassis on which the PDP is mounted and a rear glass substrate of the PDP in the aging device is more in the surface direction than in the thickness direction. Aging is performed by arranging a thermally conductive anisotropic sheet having a large thermal conductivity. With such a feature, the in-plane temperature of the PDP can be made more uniform during aging. Therefore, if this aging method is used, even when aging is performed under severe conditions in which a higher voltage is applied, “cracking” caused by the difference in the in-plane temperature of the PDP will occur.
Can be effectively prevented. Further, if aging is performed by this aging method, the panel characteristics after aging are more uniform. Therefore, in the final product,
It is possible to prevent color unevenness from occurring in the displayed image.

According to a second aspect of the present invention, there is provided a method for aging a PDP, comprising the steps of: providing a thermally conductive anisotropic sheet having a relatively higher thermal conductivity in a plane direction than a thickness direction; Aging is carried out on a front glass substrate of a PDP so as to straddle the boundary of. Due to such a feature, during aging, heat conduction from the high-temperature display portion to the low-temperature non-display portion is promoted, and the temperature difference between the two is reduced. This effectively prevents "cracks" near the boundary caused by the temperature difference between the display part and the non-display part. Therefore, using this aging method,
Even when aging is performed under severe conditions for applying a higher voltage, “cracking” at the boundary between the display unit and the non-display unit can be effectively prevented.

The PDP aging method according to the third aspect of the present invention is a combination of the first and second aspects of the invention. By combining both, the in-plane temperature of the PDP during aging can be made more uniform, and the temperature difference between the display part and the non-display part can be made smaller. Thereby, cracking of PDP during aging is further suppressed, and panel characteristics are more uniform in the final product.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing an aging method for a plasma display panel according to the present invention.

FIG. 2 is a plan view schematically showing a plasma display panel aging method of the present invention.

FIG. 3 is a plan view schematically showing a state in which a thermally conductive anisotropic sheet is placed on a plasma display panel so as to straddle a boundary between a display unit and a non-display unit in the aging method for a plasma display panel of the present invention. .

[Explanation of symbols]

1. Plasma display panel (PDP), 1a ...
Back glass substrate, 1b ... front glass substrate, 100 ... chassis, 102 ... heat conductive anisotropic sheet, 104 ... heat conductive anisotropic sheet.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koji Aoto 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 5C012 VV01 5C040 JA26 JA40

Claims (8)

[Claims] 1. A plasma display panel aging method for lighting all discharge cells of a display unit of a plasma display panel, wherein the thermal conduction anisotropy has a relatively higher thermal conductivity in a plane direction than in a thickness direction. A plasma display panel aging method in which a sheet is disposed between a chassis on which the plasma display panel is mounted and a rear glass substrate of the plasma display panel to perform aging. 2. A method of aging a plasma display panel for lighting all discharge cells of a display unit of the plasma display panel, wherein the thermal conduction anisotropy has a relatively higher thermal conductivity in a plane direction than in a thickness direction. A plasma display panel aging method in which a sheet is placed on a front glass substrate of a plasma display panel so as to straddle a boundary between a display portion and a non-display portion of the plasma display panel, and aging is performed. 3. A method of aging a plasma display panel for lighting all discharge cells of a display unit of a plasma display panel, wherein the thermal conduction anisotropy has a relatively higher thermal conductivity in a plane direction than in a thickness direction. A sheet is arranged between the chassis on which the plasma display panel is mounted and the back glass substrate of the plasma display panel, and a heat conductive anisotropic sheet having a relatively larger heat conductivity in the surface direction than in the thickness direction. An aging method for a plasma display panel, wherein the aging is performed on a front glass substrate of the plasma display panel so as to straddle a boundary between a display unit and a non-display unit of the plasma display panel. 4. The heat conductive anisotropic sheet is mounted on a front glass substrate of a plasma display panel so as to straddle a display portion and a non-display portion over a range of 1 to 2 cm from a boundary between a display portion and a non-display portion. The method for aging a plasma display panel according to claim 3. 5. A graphite sheet as a thermally conductive anisotropic sheet, disposed between a chassis and a back glass substrate of a plasma display panel.
Aging method for a plasma display panel according to the above. 6. The plasma display panel according to claim 2, wherein a graphite sheet is mounted on the front glass substrate of the plasma display panel so as to straddle a boundary between a display portion and a non-display portion of the plasma display panel. The aging method for a plasma display panel according to the above item. 7. The graphite sheet is 700 to 800 W
/ (M · k) in the plane direction.
An aging method for a plasma display panel according to claim 5. 8. A method for manufacturing a plasma display panel, comprising the aging method for a plasma display panel according to claim 1.