JP2007305444A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel equipped with an exhaust pipe with high reliability of a sealing portion by shortening working hour and reducing man-hour in the sealing process of the exhaust pipe. <P>SOLUTION: The plasma display panel has a discharge space formed by arranging a front plate and a rear plate in opposition and by sealing the surrounding of the both plates and an exhaust pipe of tubular shape which fills a discharge gas into the discharge space by exhausting the discharge space. The exhaust pipe 21 has a sealing planned portion 21a which is narrowly constricted between both ends. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plasma display panel (hereinafter also referred to as a PDP) that is a flat panel display device used for large televisions, public displays, and the like, and more particularly, exhausts the inside of a PDP tube or encloses a predetermined gas in the tube. The present invention relates to a PDP provided with an exhaust pipe for use in processing.

  Among display devices that are tube products, PDPs can achieve higher definition and larger screens, so commercialization has progressed toward 65-inch class television receivers, large public display devices, etc. Products over 100 inches are also planned.

  Basically, a PDP is composed of a front plate and a back plate. The front plate is a transparent glass substrate, a display electrode composed of a striped transparent electrode and a metal bus electrode formed on one main surface, and a dielectric covering the display electrode and acting as a capacitor. The body layer and a protective layer made of magnesium oxide (MgO) formed on the dielectric layer. On the other hand, the back plate is a glass substrate provided with pores for exhaust and discharge gas encapsulation (also referred to as introduction), and stripe-shaped address electrodes (also referred to as data electrodes) formed on one main surface thereof, It is composed of a base dielectric layer that covers the address electrodes, a partition formed on the base dielectric layer, and a phosphor layer that emits red, green, and blue light formed between the partitions.

  The front plate and the back plate are opposed to each other on the electrode forming surface side, and the exhaust pipe and discharge gas in the discharge space partitioned by the partition wall are sealed by the surroundings and exhaust and discharge gas introduction exhaust pipes with a sealing material. Is carried out through an exhaust pipe, and the exhaust pipe (so-called tip pipe, hereinafter referred to as the tip pipe) is locally heated and melted (chip off) at an appropriate location for hermetic sealing. Is done. The completed PDP is discharged by selectively applying a video signal voltage to the display electrodes, and ultraviolet rays generated by the discharge excite each color phosphor layer to emit red, green, and blue light, thereby displaying a color image. Is realized.

  FIG. 6 is a cross-sectional view showing an example of a conventional exhaust pipe used for a PDP. The exhaust pipe shown in FIG. 6 (a) has a funnel shape with the end on the side connected to the exhaust pore being narrowed, and the exhaust pipe shown in FIG. It is formed in a shape in which a disk-like base is added to the end on the connecting side. FIG. 6C shows an unprocessed exhaust pipe. The exhaust pipes shown in FIGS. 6A and 6B are in a state in which the end on the side connected to the exhaust pore is directed upward and the end connected to the exhaust device is directed downward. Is shown.

  In addition, low melting point glass mainly composed of lead oxide has been used for the PDP dielectric layer and sealing material described above, but "lead-free" which does not contain lead components in consideration of environmental issues in recent years. An example of using a lead-free material called “lead-less” is disclosed (for example, see Patent Documents 1, 2, 3, 4 and the like). In addition, conventional exhaust pipes that have been formed of lead-containing borosilicate glass that has a relatively low softening point and excellent sealing process operability have been used. The direction of using non-lead glass is changing.

  When the PDP exhaust pipe is hermetically sealed, a local heat sealing means using a fixed gas burner, an energizing heater or the like is used. A sealing method using this local heating sealing means has been widely used conventionally, and the closed sealing planned portion of the fixed exhaust pipe is locally heated by a fixed gas burner or a current heater, melted, and melted. (For example, refer patent document 5 etc.). Conventionally, the exhaust pipe used for exhausting PDP and discharge gas is chipped off, that is, the sealing process is large and thick exhaust pipe is electrothermally sealed, and thin and thin exhaust pipe is fixed gas burner. It was common to use and seal.

  In addition, when non-lead glass is used for the exhaust pipe in consideration of the environment, the softening point of borosilicate glass that does not contain lead increases, so the heat capacity is large when using a thick exhaust pipe with a large thickness. In many cases, electrothermal sealing by heating with an energized heater is used as the local heat sealing means. Electrothermal sealing can control the heating temperature relatively accurately, is easy to handle in mass production and easy to automate, but has a larger heating part (electric heater) than the method using a fixed gas burner. In addition, the time required for heating and cooling becomes long, and it is not easy to increase the manufacturing tact. For this reason, it is hoped that a fixed gas burner should be used in the case of an exhaust pipe for PDP, which uses a relatively thin and thin exhaust pipe formed of a lead-free borosilicate hard glass. It is rare.

FIG. 7 is a sectional view showing a procedure of a conventional exhaust pipe sealing method. FIG. 7 shows an exhaust pipe formed in a funnel shape by expanding an end portion on the side connected to an exhaust pore (not shown) provided on a glass substrate (not shown) of a display device such as a PDP. The structure which seals 71 with the fixed gas burner 72 is shown. In FIG. 7, the sealing target portion 70 of the exhaust pipe 71 connected to the exhaust head 75 is heated by a heating flame 73 of a local heating sealing means such as a fixed gas burner 72 (FIG. 7A). Then, the planned sealing portion 70 of the exhaust pipe 71 is softened, and the biasing force in the direction of arrow C by the elastic means 74 such as a spring provided in the exhaust head 75 and the negative pressure in the exhaust pipe 71 in the planned sealing portion 70. Then, the glass wall in the softened state in the portion 70 to be sealed of the exhaust pipe 71 is melted and melted by the surface tension at the joint 76 (FIG. 7B). (C)), the urging force in the direction of arrow C further acts on the joining portion 76 to be cut, and the sealing portion 77 is formed to complete the sealing of the exhaust pipe 71 (FIG. 7D).
JP 2002-053342 A JP 2001-045875 A Japanese Patent Laid-Open No. 09-050769 JP 2003-596697 A JP 7-057637 A

  However, when the exhaust pipe 71 is sealed with the fixed gas burner 72 as in the prior art, the sealing target portion 70 of the hollow exhaust pipe 71 is locally heated and sealed like the fixed gas burner 72 as shown in FIG. It is necessary to heat and soften by the heating flame 73 of the stopping means, and to apply and apply an urging force in the direction of arrow C by the elastic means 74 such as a spring provided in the exhaust head 75 to narrow the sealing target portion 70 narrowly. At this time, it is complicated to finely adjust the heating force of the heating flame 73 of the local heating sealing means such as the fixed gas burner 72 and the urging force applied in the direction of the arrow C by the elastic means 74. Pull-in occurs in the planned sealing portion 70 and holes are formed, and the glass does not soften and melt uniformly in the planned sealing portion, resulting in a thickened wall or an extremely thin tube wall. Remained, causing leaks and damage.

  Further, in the exhaust pipe sealing step whose procedure is shown in FIG. 7, it takes the most time for the work of narrowing the planned sealing portion 70 of the exhaust pipe 71 as shown in FIG. Shortening the working time at this time has been required for reducing the number of steps in the sealing process.

  The present invention solves the above-described problems, and in the exhaust pipe for exhausting the inside of the PDP pipe or sealing the gas in the pipe, even when the exhaust pipe made of non-lead glass is sealed with a fixed gas burner, PDP with exhaust pipe for reducing the work time by reducing the work time in the sealing process, reducing the man-hours, and reducing the product price, without any deterioration of the sealing part due to the occurrence of cracks and leaks The purpose is to provide.

  In order to achieve the above object, the PDP according to the present invention has a front plate and a back plate facing each other and seals the periphery of both substrates to form a discharge space, exhausts the discharge space, and discharges into the discharge space. The PDP includes a tubular exhaust pipe that encloses a gas, and uses an exhaust pipe that has a narrow sealing portion between both ends. In addition, the PDP of the present invention is not only configured using an exhaust pipe in which the ratio of the thickness to the outer diameter is 0.18 or less, but the exhaust pipe is formed using borosilicate glass containing no lead. You may have the structure which has.

  Because of these configurations, it is made of borosilicate glass that does not contain lead, and it is used for exhaust pipes that have narrow constricted portions between both ends, greatly reducing the work time required for the sealing process. In addition, the ratio of the thickness of the exhaust pipe to its outer diameter is regulated to 0.18 (the nominal outer diameter is 5.0 mmφ and the wall thickness is less than 0.9 mm). Even when sealing is performed, the glass thickness of the sealing portion can be made uniform, and a strong sealing portion free from residual stress due to thermal strain can be formed in the sealing portion, and leakage and cracks in the sealing portion can be prevented. A highly reliable PDP that does not occur can be realized. In addition, since an exhaust pipe made of borosilicate glass that does not contain lead is used, it is possible to realize a lead-free product as a whole and to provide an excellent display device that can eliminate adverse effects on the environment. it can.

  According to the PDP of the present invention, even when an exhaust pipe made of lead-free glass is sealed with a fixed gas burner, there is no decrease in reliability due to a failure of the sealing portion such as cracks and leaks, and the manufacturing tact is increased and man-hours are increased. It is possible to realize a display device which is reduced in quality and inexpensive.

  Hereinafter, a PDP according to an embodiment of the present invention will be described in detail with reference to the drawings.

(Embodiment)
FIG. 1 is an exploded perspective view showing a structure of a PDP in an embodiment of the present invention, and FIG. 2A is a plan view showing a state in which a front plate and a rear plate of the PDP in the embodiment of the present invention are sealed and joined. FIG. 2 and FIG. 2B are cross-sectional views taken along line AA of the PDP shown in FIG. The basic structure of the PDP is the same as that of a general AC surface discharge type PDP.

  As shown in FIG. 1, the PDP 20 has a front plate 22 made of the front glass substrate 1 and the like and a back plate 23 made of the back glass substrate 8 and the like, and the outer periphery thereof is sealed with glass frit or the like. The material is hermetically sealed. A discharge gas is sealed at a predetermined pressure in the discharge space 14 inside the sealed PDP 20.

  On the front glass substrate 1 of the front plate 22, a pair of striped display electrodes 4 and light shielding layers 5 each consisting of the scanning electrodes 2 and the sustaining electrodes 3 are arranged in parallel to each other in a plurality of rows. A dielectric layer 6 serving as a capacitor is formed on the front glass substrate 1 so as to cover the display electrode 4 and the light shielding layer 5, and a protective layer 7 made of magnesium oxide (MgO) or the like is further formed on the surface. Has been.

  On the back glass substrate 8 of the back plate 23, a plurality of stripe-shaped address electrodes 10 are arranged in parallel to each other in a direction orthogonal to the display electrodes 4 of the front plate 22, and the underlying dielectric layer 9 is disposed on the back glass substrate 8. It is covered. Further, on the base dielectric layer 9 between the address electrodes 10, barrier ribs 11 having a predetermined height are formed to divide the discharge space 14. Phosphor layers 12R, 12G, and 12B that emit red, blue, and green light by ultraviolet rays are sequentially applied and formed in the grooves between the barrier ribs 11 for each address electrode 10. A discharge cell is formed at a position where the scan electrode 2, the sustain electrode 3 and the address electrode 10 intersect, and the discharge cell having red, blue and green phosphor layers 12R, 12G and 12B arranged in the direction of the display electrode 4 is colored. It becomes a pixel for display.

  Scan electrode 2 is composed of transparent electrode 2a and metal bus electrode 2b, and sustain electrode 3 is composed of transparent electrode 3a and metal bus electrode 3b.

  Next, a method for manufacturing the PDP in the embodiment of the present invention will be described. As shown in FIG. 2, the front plate 22 and the back plate 23 face each other on the electrode forming surface side, and the display electrodes 4 and the address electrodes 10 are arranged so as to be orthogonal to each other. The periphery of the widened end portion of the exhaust pipe 21 arranged so as to cover the exhaust pores 30 provided at predetermined positions is sealed with sealing materials 31 and 32 such as glass frit. Next, after the discharge space 14 is evacuated through the exhaust pipe 21, a discharge gas containing neon, xenon, and the like is similarly supplied from the exhaust pipe 21 to a predetermined pressure (for example, a pressure of 400 Torr to 600 Torr in the case of Ne—Xe mixed gas). Then, the exhaust pipe 21 is locally heated and melted and sealed at an appropriate portion to be hermetically sealed (chip-off), thereby completing the PDP 20. The completed PDP is discharged by selectively applying a video signal voltage to the display electrodes, and the ultraviolet rays generated by the discharge excite each color phosphor layer to emit red, green, and blue light to display a color image. Realized. For sealing the exhaust pipe 21, a sintered sealing material 32 called a tablet having a hole in the center is used.

  When sealing the exhaust pipe of the PDP, local heat sealing means such as a fixed gas burner or an energizing heater is used. Electrothermal sealing using an energizing heater, etc. can control the heating temperature relatively accurately, and has the advantage of being easy to handle during mass production and easy to automate. In the embodiment of the present invention, the exhaust pipe is sealed with a fixed gas burner because the heater) becomes large and the time required for heating and cooling becomes long and it is not easy to increase the manufacturing tact. Worked.

  3A to 3C are sectional views showing examples of exhaust pipes used in the PDP according to the embodiment of the present invention. Each of the exhaust pipes 21 is formed by processing a straight tube having an outer diameter of about 5.0 mmφ into a shape having a planned sealing portion 21a narrowed between both ends. The exhaust pipe 21 shown in FIG. 3A is formed in a funnel shape with the end connected to the exhaust pore provided on the glass substrate of the display device such as the PDP 20 being expanded. The exhaust pipe 21 shown in FIG. 5 is formed in a shape in which a disk-like base portion is added to an end portion connected to an exhaust pore provided on a glass substrate of a display device such as a PDP 20. Further, FIG. 3C shows an exhaust pipe 21 that is generally used for a tube product, and the end portion is not processed. 3 (a) and 3 (b), the exhaust pipe 21 shown in FIGS. 3 (a) and 3 (b) has an end connected to the exhaust pore provided on the glass substrate of the PDP 20 on the upper side and an end connected to the exhaust device on the lower side. The state toward is shown.

  And the exhaust pipe 21 used for PDP20 in embodiment of this invention is formed using the borosilicate type | system | group glass which does not contain a lead component and whose heat conductivity is comparatively small. For example, a lead-free alkali borosilicate glass (product name “FE-2”) manufactured by Nippon Electric Glass Co., Ltd. can be used. Strictly speaking, the lead-free alkali borosilicate glass “FE-2” does not contain lead at all, and when analyzed, a trace amount of lead is detected at the PPM level. However, since the EC-RoHS directive in Europe can be regarded as not containing lead if it is 1000 PPM or less, even in the embodiment of the present invention, “lead-free”, “lead-free”, “non-lead” "Is used.

  Next, the sealing process for sealing the exhaust pipe 21 and the exhaust pipe 21 will be described with reference to FIGS. 4 and 5. FIG. 4A is a cross-sectional view showing a state in which an exhaust pipe is attached to an exhaust head in order to perform exhaust, discharge gas sealing, and sealing of a PDP according to an embodiment of the present invention, and FIG. FIG. 5A to FIG. 5C are cross-sectional views illustrating a procedure for sealing the exhaust pipe of the PDP in the embodiment of the present invention. In the sealing step of the exhaust pipe 21 of the PDP 20 in the embodiment of the present invention, the sealing scheduled portion 21a of the fixed exhaust pipe 21 is heated, melted, and melted and cut.

  In FIG. 4, an exhaust pipe 21 made of lead-free borosilicate glass disposed and sealed so as to cover the exhaust pores 30 provided at predetermined positions on the back plate 23 of the display device such as the PDP 20 is shown in FIG. Although the exhaust pipe having the shape shown in (a) is used, the sealing process can be performed in the same procedure in the case of the exhaust pipe shown in FIGS. 3 (b) and 3 (c).

  First, the sealed PDP 20 is disposed on a panel fixing base (not shown) so that the straight tubular end of the exhaust pipe 21 faces downward. An exhaust head 41 is attached to the end of the straight pipe of the exhaust pipe 21, the inside of the PDP 20 heated in a furnace at a predetermined temperature is exhausted and discharge gas is sealed, and then the sealing portion 21 a of the exhaust pipe 21 is sealed. A fixed gas burner 43 for heating the outer periphery is arranged. The exhaust head 41 is provided with a biasing means 42 using a spring or the like so that a biasing force is applied to the exhaust pipe 21 downward (a direction indicated by an arrow C in FIG. 4A). The heating flame 44 of the fixed gas burner 43 preferably has a plurality of heating flames 44 horizontally in a plane perpendicular to the exhaust pipe 21 as shown in FIG.

  When the outer periphery of the sealing portion 21a of the exhaust pipe 21 is heated to a predetermined temperature by the heating flame 44 of the fixed gas burner 43, the glass is softened, and the inside of the exhaust pipe 21 communicating with the discharge space 14 is in a reduced pressure state. Due to the urging force of the urging means 42, the upper and lower portions of the planned sealing portion 21a extend and become thinner. Further, when the scheduled sealing portion 21a of the exhaust pipe 21 is continuously heated by the heating flame 44 of the fixed gas burner 43, the inner surface of the exhaust pipe 21 comes into contact as shown in FIG. 21b is formed, and the glass is in a uniform molten state. After this, the melt-bonded portion 21b further extends and narrows and is finally cut, but a sealing portion 21c having a protruding shape at the end is formed, and the sealing of the exhaust pipe 21 is completed. Unlike the exhaust pipe 21 used in the conventional sealing process, the exhaust pipe 21 used in the PDP 20 in the embodiment of the present invention has a narrow sealing portion 21a narrowed between both ends of the exhaust pipe 21, as shown in FIG. Therefore, the time required for the sealing process can be greatly shortened. 4 and 5, the exhaust head 41 is described as being disposed below the exhaust pipe 21, but a configuration in which the exhaust head 41 is disposed above the exhaust pipe 21 is also possible.

  When some of the sealing portions 21c of the PDP 20 provided with the exhaust pipe 21 made of borosilicate glass not containing lead in the embodiment of the present invention are sampled and observed, the sealing portion 21c as shown in FIG. There are those that are sealed in a shape where the thickness of the glass is substantially uniform in the vicinity of, and those that have a thick reservoir or a sealing portion that is extremely thin and has a biased part . When these PDPs 20 were subjected to a repeated cooling test, there was no problem with the sealing part 21c having a substantially uniform glass thickness as shown in FIG. 5 (c). In the case where the wall thickness is uneven and the wall has an extremely thin sealing portion, leaks or cracks frequently occur and breakage occurs frequently. Examination of the measurement data of the thickness and outer diameter of the exhaust pipe 21 of these PDPs 20 revealed that good and defective products were classified by the thickness of the exhaust pipe 21. In the exhaust pipe 21 having a nominal outer diameter of 5.0 mmφ, the wall thickness was distributed in the range of 0.85 mm to 1.1 mm, but the wall thickness was less than 0.9 mm (the inner diameter was larger than 3.2 mm). In FIG. 5C, the sealing portion 21c of the exhaust pipe 21 is sealed in a substantially uniform glass thickness, and there was no abnormality even in the repeated cooling and heating test. However, in the exhaust pipe 21 with a nominal outer diameter of 5.0 mmφ having a thickness of 0.9 mm or more (inner diameter is 3.2 mm or less), the thickness of the glass of the sealing portion is sealed in a substantially uniform shape, Some of them have no abnormalities even in the repeated cooling and heating test, but there are some that have poor thickness in the repeated cooling and heating test with a non-uniformly thick sealing portion in a state where the thickness of the reservoir is extremely thin. In the case of a sealing portion having a substantially uniform thickness of glass as shown in FIG. 5 (c), there is little distortion in the sealing portion, but there is a buildup or the thickness is extremely thin. Thus, it is shown that the distortion due to the residual stress remains in the non-uniformly sealed portion.

  Therefore, 7 types of lead having a nominal outer diameter of 5.0 mmφ and thicknesses of 0.7 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm and 1.1 mm are used. An exhaust pipe for PDP not containing borosilicate glass was prepared, a PDP sample in which the exhaust pipe was sealed by the above-described process was prepared, and an appearance inspection of the sealing portion and a repeated cooling test were performed. The shape of the sealing part of the PDP using the exhaust pipes with wall thicknesses of 0.7 mm, 0.8 mm, and 0.85 mm is sealed to a shape with a substantially uniform glass thickness as shown in FIG. There was no problem even in the repeated heating and cooling test. On the other hand, in a PDP using an exhaust pipe with a wall thickness of 0.9 mm, 0.95 mm, 1.0 mm, and 1.1 mm, the thickness of the exhaust pipe becomes thicker and the thickness is uneven and the thickness is uneven. There was an increase in the number of parts having a sealing portion with a large thickness, and even in the repeated heating and cooling test, the occurrence of defects such as leaks and cracks tended to become more pronounced as the thickness increased.

  From the above results, when sealing with a fixed gas burner using a lead-free borosilicate glass-based exhaust pipe having a nominal outer diameter of 5.0 mmφ in the embodiment of the present invention, the thickness of the exhaust pipe is reduced to 0. When the thickness is less than .9 mm, the sealing portion is formed to have a uniform thickness, and it can be said that defects such as leakage and cracks in the sealing portion do not occur. However, even when an exhaust pipe having a nominal outer diameter of 5.0 mmφ is used, if the wall thickness is smaller than 0.4 mm (the inner diameter is larger than 4.2 mm), the wall thickness is too thin and the glass tube is used in the sealing process. It is confirmed that a leak occurs due to tearing or formation of small holes, and the wall thickness must be 0.4 mm or more.

  Subsequently, in the case of sealing with a fixed gas burner using a borosilicate glass-based exhaust pipe 21 having a nominal outer diameter different from 5.0 mmφ and not containing lead, the shape and cooling heat of the sealing portion 21c The results of the repeated test will be described.

  The prepared exhaust pipe 21 has four types of nominal outer diameters of 3.0 mmφ, 4.0 mmφ, 6.0 mmφ, and 7.0 mmφ. Using these exhaust pipes, a PDP sample in which the exhaust pipe was sealed by the above-described process was prepared, and an appearance inspection and a cooling / heating repetition test of the sealed portion were performed. In the case of an exhaust pipe having a nominal outer diameter of 5.0 mmφ, a wall thickness of 0.9 mm is the boundary, and in an exhaust pipe having a thickness of less than 0.9 mm, almost all of the sealing portion is as shown in FIG. It has been described that the glass wall is sealed in a substantially uniform shape, and there are no defects in the sealing part such as leaks or cracks in the repeated heating and cooling test, but the nominal outer diameter is 4 mm, which is different from 5.0 mmφ. It became clear that each kind of exhaust pipe also had a wall thickness of the boundary glass tube.

  That is, from the measured thickness of each exhaust pipe, the thickness of the exhaust pipe having a nominal outer diameter of 3.0 mmφ is 0.54 mm, the thickness of the exhaust pipe having a nominal outer diameter of 4.0 mmφ is 0.72 mm, and the nominal outer diameter is 6.0 mmφ. In the exhaust pipe, the wall thickness is 1.08 mm, and in the exhaust pipe having a nominal outer diameter of 7.0 mmφ, the wall thickness is 1.26 mm. From these results, it was found that the ratio of the wall thickness to the outer diameter of the exhaust pipe was 0.18, which was constant regardless of the nominal outer diameter value. Therefore, it is considered that the relationship can be generalized by defining the exhaust pipe thickness / exhaust pipe outer diameter = 0.18 instead of the numerical values of the outer diameter and the thickness of the exhaust pipe. .

  As described above, the exhaust pipe used for the PDP in the embodiment of the present invention is made of borosilicate glass that does not contain lead, and has a sealing portion narrowed between both ends. It is possible to significantly reduce the work time required for the sealing process, reduce the man-hours, and realize an inexpensive PDP. At the same time, the ratio of the wall thickness to the outer diameter of the exhaust pipe is regulated to 0.18 (the nominal outer diameter is 5.0 mmφ and the wall thickness is less than 0.9 mm). Can be formed uniformly, a strong sealing portion free from residual stress due to thermal strain can be formed, and a highly reliable PDP free from leakage and cracks in the sealing portion can be realized. . In addition, since an exhaust pipe made of borosilicate glass not containing lead is used, it is possible to realize lead-free PDP products as a whole, and to eliminate adverse effects on the environment.

  In the above description, the PDP is taken as an example. In addition to the PDP, the exhaust pipe used in the embodiment of the present invention is not only a display device such as a CRT, FED, SED, fluorescent display tube, but also an illumination device, It can also be used for tube products such as medical devices and physics and chemistry equipment.

  The PDP of the present invention uses an exhaust pipe made of a borosilicate glass not containing lead and having a narrow constricted sealing portion between both ends thereof. Further, the ratio of the wall thickness to the outer diameter of the exhaust pipe is set. Because it stipulates 0.18, the work time required for the sealing process can be greatly shortened and the number of man-hours can be reduced. Even if sealing is performed with a fixed gas burner, the glass thickness of the sealing part is uniform. It is possible to form an inexpensive PDP that is highly reliable and does not cause defects such as leaks and cracks in the sealing portion, and is suitable for the environment, and is effective when applied to a display device such as a large-screen TV. .

The disassembled perspective view which shows the structure of PDP in embodiment of this invention (A) is a top view which shows the state which sealed and joined the front plate and back plate of PDP in embodiment of this invention. (B) is the sectional view on the AA line part of PDP shown to (a). Sectional drawing which shows the example of the exhaust pipe used in PDP of embodiment of this invention (A) is sectional drawing which shows the state in which the exhaust pipe was attached to the exhaust head in order to perform exhaust_gas | exhaustion of PDP, discharge gas enclosure, and sealing in embodiment of this invention, (b) is BB in (a). Line section (A)-(c) is sectional drawing explaining the procedure which seals the exhaust pipe of PDP in embodiment of this invention Sectional drawing which shows the example of the conventional exhaust pipe used for PDP (A)-(d) is sectional drawing which shows the procedure of the sealing method of the conventional exhaust pipe

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front glass substrate 2 Scan electrode 2a, 3a Transparent electrode 2b, 3b Metal bus electrode 3 Maintenance electrode 4 Display electrode 5 Light-shielding layer 6 Dielectric layer 7 Protective layer 8 Back glass substrate 9 Base dielectric layer 10 Address electrode (data electrode)
11 Partition 12R, 12G, 12B Phosphor layer 14 Discharge space 20 Plasma display panel (PDP)
21, 71 Exhaust pipe (chip pipe)
21a, 70 to be sealed 21b, 76 (melting) joint 21c, 77 sealing 22 front plate 23 back plate 30 exhaust pores 31, 32 sealing material 41, 75 exhaust head 42 biasing means 43, 72 Fixed gas burner 44, 73 Heating flame 74 Elastic means

Claims (3)

A plasma having a tubular exhaust pipe in which a front plate and a back plate are arranged to face each other and the periphery of both substrates is sealed to form a discharge space, the discharge space is exhausted, and discharge gas is sealed in the discharge space. A display panel,
A plasma display panel characterized by using an exhaust pipe having a narrowly sealed portion between both ends. 2. The plasma display panel according to claim 1, wherein an exhaust pipe having a thickness ratio to an outer diameter of 0.18 or less is used. 3. The plasma display panel according to claim 1, wherein the exhaust pipe is formed using borosilicate glass not containing lead.

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