JP4929080B2 - Plasma display panel and manufacturing apparatus thereof - Google Patents

Description

  In the field of plasma display panels (hereinafter also referred to as plasma panels or PDPs), the present invention relates to a method for producing PDP and a PDP or PDP production apparatus using the method, in order to contain impurity components when sealing discharge gas. The present invention relates to a technology that prevents re-encapsulation and does not contaminate the inside of the discharge gas.

  In recent years, a plasma display device is expected as a large and thin color display device. In particular, an alternating current (AC) in-plane discharge type PDP that generates display discharge between electrodes provided on the same substrate and is driven by alternating current is most practically used because of its simple structure and high reliability. This method

  In general, a PDP is composed of two glass substrates: a front glass plate on which a sustain discharge is formed, a dielectric and a protective film and an address electrode, and a rear glass plate on which phosphors and barrier ribs are formed. After assembling the panel by sealing with a sealing member, a gas (discharge gas) for generating plasma is sealed through a glass exhaust pipe (also called a P pipe) joined to the back glass plate side, and the glass pipe It is manufactured by overheating and sealing. It is necessary to maintain the airtightness of the discharge gas in sealing and sealing the front and rear glass plates.

  FIG. 1 shows a configuration diagram of a PDP manufacturing apparatus for sealing and sealing front and rear glass plates. FIG. 1 shows an apparatus capable of simultaneously manufacturing three panels as an example. The number of sheets that can be manufactured at the same time can be any number by adding equipment. As described above, the panels 1 to 3 in which the front glass plate, the rear glass plate, the sealing member, and the P tube are assembled are installed in the baking furnace 7 as shown in FIG. The panels 1 to 3 can be evacuated by the operation valves 17 to 21 of the respective pumps through the exhaust heads 4 to 6, the valves 11 to 13, and the manifold 14, respectively. Vacuum evacuation is possible by a combination of a turbo molecular pump 22 for high vacuum evacuation and a mechanical pump 23 for rough evacuation. The panel is heated in the baking furnace 7 to a temperature at which the sealing member melts to 400 ° C. or higher, whereby the glass plate, the back glass plate and the P-tube are sealed, and sealed as a container capable of being vacuum-tight. After sealing, impurities (water, carbon monoxide, nitrogen, etc.) that are evacuated by the turbo molecular pump 22 and the mechanical pump 23 described above, and heated to a temperature of about 350 ° C. or higher and adhered to the panel. Evaporating substances such as argon, carbon dioxide, organic substances contained in the sealing material), and evacuating the panel. After evaporation for several hours, the panel is turned off and evacuated while cooling. When the temperature is near room temperature, the evacuation is stopped and a discharge gas (a rare gas mixture such as neon, xenon, helium, or argon) is placed inside the panel. Enclose. The discharge gas sealing adjusts the pressure of the desired discharge gas from the cylinders 28 and 33 through the pressure regulators 27 and 32, and passes through the filters 26 and 31, the needle valves 25 and 30, and the stop valves 8 to 10, 25 and 29, The discharge gas is sealed while controlling the gas pressure in each panel. The enclosed gas pressure is in the range of 50-100 kPa. The gas pressure of the discharge gas and the degree of vacuum during evacuation are measured using a vacuum gauge 15 to control each valve. A very small amount of impurity gas component analysis in the discharge gas or vacuum exhaust is performed with a high-precision impurity gas component analyzer 16 at the ppt level using a gas chromatography, an atmospheric pressure ion mass spectrometer or the like used in the semiconductor field. Can be used.

  FIG. 2 shows an enlarged view around the exhaust head 6 shown in FIG. The front glass plate 34, the back glass plate 35, the sealing members 36 and 37, and the P tube 38 are assembled and installed in the baking furnace 7 surrounded by the baking furnace wall 45. The P pipe 38 is connected to the exhaust and gas introduction pipe 41 via the sealing material 40 in the exhaust head 6. The heater 39 in the exhaust head 6 is used when sealing the panel after gas filling is completed.

  As shown in FIG. 2, the conventional PDP gas introduction and exhaust path is performed by sharing one pipe 41 in the baking furnace 7. At that time, the impurity components that are generated at the time of sealing by vacuum evacuation of the panel are removed through the pipe 41. Since the inside of the baking furnace is heated to a temperature of about 350 ° C. or higher during evacuation, the impurity component is almost exhausted and removed. However, the temperature of the inner wall of the pipe outside the baking furnace 7 is low, so some of the residual impurities It remains as component 44. When the discharge gas is sealed after evacuation, the residual impurity component 44 is reintroduced into the panel again, resulting in variations in the discharge characteristics of the panel. In particular, the discharge voltage around the P tube increases, and problems such as no improvement in discharge characteristics occur even when a high-purity discharge gas is introduced.

  By supplementing the residual impurity component 44 on the inner wall of the pipe outside the baking furnace 7 with a cooling trap, or separating the pipe part outside the baking furnace 7 from the discharge gas introduction pipe path by a valve inside the baking furnace when the discharge gas is introduced, The reintroduction of the residual impurity component 44 is prevented.

  According to the present invention, it becomes possible to prevent re-introduction of impurity components removed by heating and vacuum exhausting in a panel, and improving the exhaust efficiency of impurity components by using a cooling trap during heating and vacuum exhausting. I can do it. Since the influence of the impurity component does not occur, the effect can be clearly obtained even by introducing advanced technology that reduces the variation in the panel discharge characteristics and further improves the function.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for explaining the embodiments, parts having the same function are given the same reference numerals, and repeated explanation thereof is omitted.

  FIG. 3 is a structural view around the exhaust head of the PDP manufacturing apparatus equipped with the impurity component re-introduction preventing mechanism using the cooling trap of the present invention. Impurity components that come out at the time of sealing by vacuum evacuation of the panel are exhausted through the pipe 41. During the evacuation, since the inside of the baking furnace is heated to a temperature of about 350 ° C. or higher, the impurity component is almost evaporated and exhausted and removed. It remains as a residual impurity component 44. A cooling trap 46 is provided to prevent the residual impurity component 44 from being reintroduced into the panel when the discharge gas is sealed after the panel is cooled and evacuated. The cooling trap uses a solvent type, a refrigerator type, and an electronic cooling type, controls the temperature from room temperature to −120 ° C., and a desired residual impurity component 44 is reintroduced into the panel simultaneously with the discharge gas 42. Can be prevented. If the cooling temperature is −120 ° C. or lower, the xenon gas in the discharge gas 42 is trapped. Therefore, the cooling temperature is used at −120 ° C. or higher. In this embodiment, the pipe 41 connecting the exhaust pipe path and the discharge gas introduction pipe path inside the baking furnace is used. However, the pipe connecting the exhaust pipe path and the discharge gas introduction pipe path outside the baking furnace is used. However, the effect of the cooling trap was confirmed. Further, by using a cooling trap during evacuation, the exhaust efficiency of impurity removal can be improved. In this case, since the amount of impurities attached to the inner wall of the pipe outside the baking furnace 7 increases, the pipe needs to be baked according to the frequency of use to clean the inside of the pipe. The impurity component concentration in the plasma display panel manufactured by the present invention is checked by a high-precision impurity gas component analyzer at a ppt level using a gas chromatography or an atmospheric pressure ion mass spectrometer used in the semiconductor field. It can be distinguished from the PDP manufactured by the prior art.

  FIG. 4 is a structural diagram around an exhaust head of a PDP manufacturing apparatus equipped with an impurity component re-introduction preventing mechanism using a valve for separating the exhaust pipe path and the discharge gas introduction pipe path in the baking furnace of the present invention. . As described in the first embodiment, in the panel sealing step, the impurity components that are generated during sealing by vacuum evacuation of the panel are exhausted through the pipe 41. During the evacuation, since the inside of the baking furnace is heated to a temperature of about 350 ° C. or more, the impurity components are almost evaporated and exhausted and removed. However, the temperature of the inner wall of the pipe outside the baking furnace 7 is low, so some It remains as a residual impurity component 44. When the discharge gas is sealed after the panel is cooled and evacuated, in order to prevent the residual impurity component 44 from being reintroduced into the panel, gas is introduced by separating the exhaust pipe path and the discharge gas introduction pipe path. A valve 47 is provided. Since the valve 47 is used in a baking furnace, a metal valve that can be used in a high temperature environment is used. By using the valve 47, it is possible to efficiently prevent the residual impurity component 44 from being reintroduced into the panel without the cooling trap 46 used in the first embodiment, and the running cost is also reduced. Advantageously, no solvent or power is required. However, since the number of opening and closing of the metal valve is limited by the mechanical strength, it is necessary to perform maintenance periodically. FIG. 5 shows a configuration diagram when both the valve 47 and the cooling trap 46 mechanism are used. If the valve 47 and the cooling trap 46 are used at the same time, the exhaust efficiency of impurity components and the reintroduction of the residual impurity components 44 can be further removed, which is beneficial when a panel is manufactured in a high purity environment (high vacuum). It is.

  FIG. 6 shows an embodiment in which two P pipes are installed on the panel in order to separate the exhaust pipe path and the discharge gas introduction pipe path. Similar to the case described in the first and second embodiments, in the panel sealing step, the impurity component that is generated during sealing by vacuum evacuation of the panel is exhausted through the pipe 49. During the evacuation, since the inside of the baking furnace is heated to a temperature of about 350 ° C. or more, the impurity components are almost evaporated and exhausted and removed. However, the temperature of the inner wall of the pipe outside the baking furnace 7 is low, so some It remains as a residual impurity component. When the discharge gas is sealed after the panel is cooled and evacuated, a pipe 48 dedicated to the discharge gas is used. Thereby, the residual impurity component adhering to the inner wall of the pipe 49 outside the baking furnace can be prevented from being reintroduced into the panel. However, it is conceivable that the residual impurity component is reintroduced into the panel through the pipe 49 even though the amount is small. In that case, it becomes possible to completely prevent reintroduction of impurity components by installing the cooling trap 46 shown in the first embodiment and the equipment of the valve 47 in the baking furnace shown in the first embodiment. However, there are many restrictions on the panel side to install two P pipes on the panel side, and it is disadvantageous in terms of cost and yield, so care must be taken. FIG. 7 shows an example of a plasma display device using the PDP shown in the first to third embodiments and an image display system in which a video source is connected thereto. A drive power supply (also called a drive circuit) receives a display screen signal from a video source and converts it into a PDP drive signal to drive the PDP.

The block diagram of the PDP manufacturing apparatus which seals and seals a front glass plate, a back glass plate, and a P pipe in PDP of the conventional structure. The block diagram of the circumference | surroundings of the exhaust head of the PDP manufacturing apparatus shown in FIG. The block diagram which shows the impurity component reintroduction prevention mechanism using the cooling trap of this invention. The block diagram which shows the impurity component reintroduction prevention mechanism using the valve for piping separation in baking furnace of this invention. The block diagram which shows the impurity component reintroduction prevention mechanism using both the cooling trap of this invention, and the valve for piping separation in a baking furnace. The block diagram at the time of installing two P pipes of this invention, and isolate | separating an exhaust piping path and a discharge gas introduction piping path. The figure which showed the image display system using PDP.

Explanation of symbols

1,2,3 ... Plasma display panel, 4,5,6 ... Exhaust head, 7 ... Baking furnace, 8,9,10,11,12,13 , 17,18,19,20,21,24,29 ... Valve, 14 ... Manifold, 15 ... Vacuum gauge, 16 ... High-precision impurity gas component analyzer, 22 ... Turbo molecular pump, 23 ... Mechanical pump, 25, 30 ... Needle valve, 26, 31 ... Filter, 27, 32 ... Gas pressure regulator, 28, 33 ... gas cylinder, 34 ... front glass substrate, 35 ... rear glass substrate, 37 ... sealing member, 38 ... exhaust pipe (P tube), 39 ... sealing, 40 ... sealing member, 41 ... Piping, 42 ... Discharge gas introduction, 43 ... Exhaust, 44 ... Impurity component, 45 ... Baking furnace wall, 46 ... Cooling trap, 47 ... Valve , 48 ... Exhaust pipe (P pipe) connection pipe, 49 ... Pipe for exhaust in panel 50 ... plasma panel, 51 ... drive power supply, 52 ... video source, 53 ... plasma display device.

Claims (3)

At least one electrode formed on the inner surface side of each of the front glass substrate and the rear glass substrate disposed to face each other, and two electrodes for performing a counter display discharge, and a dielectric film that at least partially covers the two electrodes A plurality of discharge cells each including at least a discharge gas and a phosphor film that emits visible light by excitation by ultraviolet rays generated by discharge of the discharge gas, and between the plurality of discharge cells Connecting partition wall layer, exhaust pipe for introducing discharge gas, baking furnace for heating and exhausting to remove impurity components in the panel, and exhaust pipe and piping for filling and exhausting discharge gas In the plasma display panel manufacturing apparatus and the plasma display panel including an exhaust head for exhausting and an exhaust device in which a discharge gas is filled and exhausted is arranged,
Cooling to prevent re-introduction of impurity components removed in the vacuum exhaust process performed before introducing the discharge gas when the discharge gas is introduced through the exhaust pipe in the process of manufacturing the plasma display panel. A trap device is provided outside the baking furnace ,
An apparatus for manufacturing a plasma display panel and a plasma display panel for the same, wherein an exhaust pipe path and a discharge gas introduction pipe path are joined in the baking furnace . In a plasma display panel manufacturing apparatus and its plasma display panel,
Baking furnace to prevent re-introduction of impurity components removed in the evacuation process performed before introducing the discharge gas when introducing the discharge gas through the exhaust pipe in the process of manufacturing the plasma display panel There use a valve to separate the exhaust pipe passage discharge gas introduction pipe path within,
A plasma display panel manufacturing apparatus comprising a cooling trap device outside the baking furnace for preventing re-introduction of impurity components removed in an evacuation process performed before introducing discharge gas, and The plasma display panel. The image display system using a plasma display panel according to claim 1 or 2.

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