JP4954681B2 - Method for manufacturing plasma display panel - Google Patents

Description

  The present invention relates to a plasma display panel and a film forming apparatus used for manufacturing the plasma display panel.

Conventionally, PDPs (plasma display panels) have been widely used in the field of display devices, and in recent years, high-quality, low-cost PDPs with large screens have been required.
In general, a PDP is mainly a three-electrode surface discharge type in which a front plate in which sustain electrodes and scan electrodes are formed on a glass substrate and a back plate in which address electrodes are formed on a glass substrate are bonded together. It has become.

  A discharge gas is sealed between the front plate and the back plate. When a voltage is applied between the scan electrode and the address electrode to cause discharge, the sealed discharge gas is turned into plasma and ultraviolet rays are emitted. If the phosphor is arranged at a position where the emitted ultraviolet rays are irradiated, the phosphor is excited by the ultraviolet rays and visible light is emitted.

In general, a dielectric film is formed on the sustain electrode and the scan electrode, and an MgO protective film for protecting the dielectric is further formed thereon.
When an AC voltage is applied to the scan electrode and the sustain electrode to maintain the discharge, cations generated by the plasma of the discharge gas enter the scan electrode side and the sustain electrode side. The dielectric film is protected from cations by a protective film.

In recent years, with the demand for higher performance, a method for increasing the Xe concentration in a mixed gas of Ne and Xe, which is usually used as a discharge gas, from about 5% to 10% or more in order to improve the luminous efficiency of PDP Has been done.
However, when the protective film is MgO, if the Xe concentration in the discharge gas is increased, the discharge voltage rises, the sputtering resistance is lowered and the function as the protective film is lowered, and the panel life is shortened. there were. Also, the driver circuit for driving the PDP needs to be compatible with a high voltage specification, which raises a problem that the manufacturing cost of the PDP drive control system increases.

The discharge voltage of the PDP depends on the secondary electron emission coefficient of the protective film. It has been proposed to use an alkaline earth metal oxide having a work function smaller than that of MgO as a protective film to lower the discharge voltage. (Japanese Patent Laid-Open No. 2002-231129)
Further, if an alkaline earth metal oxide is used as a protective film and a PDP is manufactured by a vacuum integrated device proposed in Japanese Patent Laid-Open No. 2000-156160, the alkaline earth metal oxide protective film needs to be exposed to the atmosphere. Therefore, the PDP can be manufactured without impairing the characteristics of the protective film. Further, as proposed in Japanese Patent Laid-Open No. 2002-75197, if a resin material is used as the sealing material, heating and cooling at the time of sealing the panel becomes unnecessary, so that the panel manufacturing time can be greatly shortened. .

However, in the implementation of the above-described prior art using a resin material as a sealing material, the impurity gas permeates from the resin material and enters the panel, and the impurity gas released from the resin material into the panel at the time of sealing the panel. There is a problem that the discharge voltage rises due to the gradually decreasing purity of the discharge gas sealed in the panel.
JP 2002-231129 A JP 2000-156160 A JP 2002-75197 A

  The present invention has been made to solve the above-mentioned problems, and its object is to prevent the ingress of impurity gases and suppress the rise of the discharge voltage of the plasma display panel.

In order to solve the above problems, the present invention is a method in which a first substrate and a second substrate are bonded together with a resin sealing material formed in a peripheral sealing region, and plasma is generated for each pixel in the display region. A method of manufacturing a plasma display panel for generating and displaying, the step of forming an electrode on a surface of the first substrate facing the second substrate, and a dielectric contacting the surface and side surfaces of the electrode Forming a body film, and having a planar shape larger than the planar shape of the dielectric film between the display region of the first substrate and the display region and the sealing region in a reduced-pressure atmosphere; Forming a protective film so as to protrude from the outer periphery of the dielectric film, maintaining the reduced pressure atmosphere, transporting the first and second substrates to the bonding chamber, and the bonding chamber The step of filling the discharge gas with First, a step of bonding the second substrate, the pressure increased by introducing a further discharge gas to the Hagoshitsu said protective film, to contact with the partition wall having said second substrate And a step of curing the sealing material of the resin, wherein the protective film is sealed without being exposed to the atmosphere.
The present invention is the method for manufacturing a plasma display panel, wherein the protective film includes at least one metal oxide selected from the group consisting of MgO, CaO, and SrO.
This invention is a manufacturing method of the plasma display panel which has the process of collect | recovering the discharge gas in the said bonding chamber after the process of bonding said 1st, 2nd board | substrate in the said bonding chamber.
The present invention is the method of manufacturing a plasma display panel, wherein the resin is an ultraviolet curable resin, and the step of curing the sealing material of the resin includes a step of irradiating ultraviolet rays.

  The absorption film absorbs both the impurity gas generated from the sealing material in the manufacturing process and the impurity gas that penetrates the sealing material and penetrates into the interior in the finished product. The purity of the sealed discharge gas does not change, and the discharge voltage is stable without increasing. If the discharge voltage is not increased, the etching rate of the protective film is not increased, and the life of the plasma display panel is extended.

Reference numerals 2 and 3 in FIGS. 2 and 3 show the plasma display panels of the first and second examples of the present invention, and common portions are denoted by common reference numerals and described together.
FIG. 1 is a perspective view of a display area 5 which is a central portion of the plasma display panels 2 and 3 of the first and second examples, and conversely, the display area 5 of FIGS. A portion of a cross-sectional view is shown.

The plasma display panels 2 and 3 have rectangular plate-like first and second substrates 11 and 21 (here, glass substrates).
The surfaces of the first and second substrates 11 and 21 are opposed to each other at a predetermined interval. A ring-shaped sealing material 31 is arranged so as to surround the display region 5 in the ring-shaped sealing region which is the outer peripheral portion of the first and second substrates 11 and 21. The end portion on the first substrate 11 side is in close contact with the surface of the first substrate 11, and the end portion on the second substrate 21 side is in close contact with the surface of the second substrate 21. Accordingly, the first and second substrates 11 and 21 are bonded together by the sealing material 31, and the gap between the first and second substrates 11 and 21 is sealed with the sealing material 31.

A transparent electrode 15 made of ITO, ZnO or the like is disposed on the surface of the first substrate 11 facing the second substrate 21, and on the surface of the second substrate 21 facing the first substrate 11. The metal electrode 25 is arranged.
Here, there are two types of transparent electrodes 15, elongate sustain electrodes 15 a and elongate scan electrodes 15 b, and the sustain electrodes 15 a and the scan electrodes 15 b are alternately arranged at predetermined intervals.

  On the surface of the first substrate 11, the dielectric film 12 having a smaller planar shape than the inner periphery of the sealing material 31 is disposed on the inner side of the sealing material 31 and separated from the sealing material 31. The surface and the side surface of the portion surrounded by the sealing material 31 of the sustain electrode 15a and the scan electrode 15b are in contact with the dielectric film 12, and the sustain electrode 15a and the scan electrode 15b are electrically insulated.

The metal electrodes (address electrodes) 25 are elongated and are arranged at a predetermined interval so as to intersect the sustain electrodes 15a and the scan electrodes 15b.
Between the address electrodes 25, elongated partition walls 23 are formed along the longitudinal direction of the address electrodes 25. The height of the partition wall 23 from the surface of the second substrate 21 is higher than that of the address electrode 25, the tip thereof is in contact with the protective film 14, and the gap between the first and second substrates 11, 21 is the partition wall 23. It is divided.

  As described above, the gap between the first and second substrates 11 and 21 is sealed with the sealing material 31, and a discharge gas containing one or both of Xe gas and Ne gas is sealed in the sealed space. Each space which is stopped and divided by the partition wall 23 is filled with the discharge gas.

  The sustain electrode 15a, the scan electrode 15b, and the address electrode 25 are each drawn out of the sealing material 31 and connected to an external circuit. Between the selected scan electrode 15b and the address electrode 25, the external circuit When a voltage is applied, a write discharge occurs in the pixel at the portion where the selected scan electrode 15b and the address electrode 25 intersect, and a sustain discharge occurs when an AC voltage is applied between the selected scan electrode 15b and the adjacent sustain electrode 15a. The discharge gas is turned into plasma at the pixel portion.

  A protective film 14 is formed on the surface of the dielectric film 12, and since the dielectric film 12 and the transparent electrode 15 are protected from plasma by the protective film 14, they are not damaged.

  When the discharge gas is turned into plasma, ultraviolet rays are generated. On the surface of the second substrate 21, phosphor layers 22R, 22G, and 22B are formed. Here, any one color of the red phosphor layer 22R, the green phosphor layer 22G, and the blue phosphor layer 22B is located in the space between the partition walls 23 and 23, and the pixel in which ultraviolet rays are generated is located. A certain phosphor layer 22R, 22G, 22B is colored, and visible light of any one of red, green, and blue is emitted.

The dielectric film 12, the protective film 14, and the first substrate 11 are transparent. As described above, since the sustain electrode 15a and the scan electrode 15b are the transparent electrodes 15, the emitted visible light passes through the protective film 14, the dielectric film 12, the transparent electrode 15, and the first substrate 11 and is externally transmitted. To be released.
When a voltage weaker than the sustain discharge is applied between the selected scan electrode 15b and the sustain electrode 15a adjacent to the scan electrode 15b and a discharge (erase discharge) weaker than the sustain discharge occurs, The generation stops and the emission of visible light is stopped.

The plasma display panels 2 and 3 of the first and second examples each have an absorption film.
In the plasma display panel 2 of the first example, the planar shape of the protective film 14 is similar to that of the dielectric film 12, and the size thereof is substantially equal. The side surface of the dielectric film 12 and the first substrate A portion of the surface 11 outside the dielectric film 12 is exposed from the protective film 14.

  Here, the planar shape of the dielectric film 12 is a quadrangle, and the inner periphery of the sealing material 31 is a quadrangular shape along the four sides of the dielectric film 12, and the dielectric film 12 and the sealing material 31. The gap between is a square ring.

  An absorption film 35 containing one or more kinds of active metals such as Ba, Sr, and Ca is formed along the four sides of the dielectric film 12 in the square ring-shaped gap in the surface of the first substrate 11. The dielectric film 12 is surrounded by a square ring-shaped active metal absorption film 35.

  On the other hand, in the plasma display panel 3 of the second example, the planar shape of the protective film 14 is larger than that of the dielectric film 12, and is equal to or smaller than the inner circumference of the sealing material 31, The edge portion protrudes from the entire outer periphery of the dielectric film 12, and the outer periphery coincides with the inner periphery of the sealing material 31 or is located between the dielectric film 12 and the sealing material 31. Therefore, the entire periphery of the dielectric film 12 is surrounded by the edge portion of the protective film 14.

  The protective film 14 contains at least one absorbing metal oxide that absorbs water and oxygen, such as MgO, CaO, and SrO, and the protective film 14 itself has absorbency. In the plasma display panel 3 of the second example, the dielectric film 12 is surrounded by the edge portion of the protective film 14 having the absorptivity, and the edge portion becomes the absorption film 36.

  Both the active metal and the absorbing metal oxide described above absorb an impurity gas such as water or oxygen. Therefore, even if the sealing material 31 is made of a material that transmits the impurity gas such as a resin material, since the transmitted impurity gas is captured by the absorption films 35 and 36, the purity of the discharge gas does not decrease, Discharge voltage is stabilized.

Next, a manufacturing process of the plasma display panel 2 of the first example and a film forming apparatus used for the manufacturing process will be described.
Reference numeral 1 in FIG. 4 represents a film forming apparatus of the present invention, and the film forming apparatus 1 has a film forming chamber 50 for an absorption film. An evaporation source, a substrate holder, and a mask are disposed inside the film forming chamber 50 for the absorption film.

5A is a plan view for explaining the positional relationship between the vapor deposition source and the mask, and FIGS. 5B and 5C are cross-sectional views taken along the line BB in FIG. This corresponds to a cross-sectional view taken along line C. A substrate holder 51 is disposed on the ceiling side of the film forming chamber 50.
A plate-like mask 55 is horizontally disposed below the substrate holder 51. As will be described later, the substrate is carried into the film formation chamber 50, and the film formation surface of the substrate is used as the bottom wall of the film formation chamber 50. The substrate is configured to be positioned between the substrate holder 51 and the mask 55 when held horizontally by the substrate holder 51 toward the side.

In the mask 55, openings 57 a to 57 d made of through holes are formed along four sides of a right-angled square on the mask 55.
Symbols Ha to Hd in FIG. 5A are four sides of a right-angled square in which the openings 57a to 57d are arranged, and indicate arrangement axes that pass through the centers in the width direction of the openings 57a to 57d. Here, one opening 57a to 57d is arranged on each of the arrangement axes Ha to Hd, but two or more openings may be arranged on each of the arrangement axes Ha to Hd.

  Below the mask 55, an evaporation source 60 in which an evaporation material 68 is accommodated is disposed. The substrate surface is exposed on the bottom surfaces of the openings 57a to 57d of the mask 55. Portions other than the exposed portions on the bottom surfaces of the openings 57a to 57d are covered with a mask 55.

  The vapor deposition source 60 has discharge ports 67a to 67d immediately below the openings 57a to 57d of the mask 55. When the vapor of the vapor deposition material 68 is released from the discharge ports 67a to 67d, the openings of the mask 55 are opened. The vapor that has passed through 57a to 57d is configured to reach the substrate surface.

  Here, the openings 57a to 57d of the mask 55 are elongated, the longitudinal direction is arranged along the respective arrangement axes Ha to Hd, and the vapor deposition source 60 includes four vapor deposition containers 61a to 61d. Yes. And in the upper part of each vapor deposition container 61a-61d, four elongate discharge ports 67a-67d are formed in the vertically downward position of each opening part 57a-57d along the longitudinal direction of opening part 57a-57d. The vapor of the vapor deposition material 68 discharged vertically upward from the discharge ports 67a to 67d can pass through the openings 57a to 57d and reach the substrate surface.

Next, a process for manufacturing the plasma display panel 2 of the first example using the film forming apparatus 1 will be described.
The film forming apparatus 1 described above is connected to the film forming chamber for the protective film, the film forming chamber for the protective film connected to the film forming chamber, and the film forming chamber for the protective film, in addition to the film forming chamber for the absorbing film. And a carry-in chamber 41.

A vacuum exhaust system 19 is connected to each of the film forming chambers 42 and 50, and the inside of the film forming chambers 42 and 50 is evacuated.
FIG. 6A shows the first substrate 11 on which the transparent electrode 15 and the dielectric film 12 are formed. The first substrate 11 in this state is loaded into the loading chamber 41, and the loading chamber 41 is loaded. After the inside is evacuated, the film forming chambers 42 and 50 are carried into the protective film forming chamber 42 from the carry-in chamber 41 while maintaining the reduced pressure atmosphere (vacuum atmosphere) inside.

  An evaporation source that emits a vapor of metal oxide and a mask are disposed inside the protective film forming chamber 42. The surface of the first substrate 11 is located outside the dielectric film 12. With the edge covered with a mask, metal oxide vapor is released, and a protective film 14 made of a metal oxide thin film is formed on the surface of the dielectric film 12.

FIG. 6B shows the first substrate 11 in a state where the protective film 14 is formed. The protective film 14 is not formed outside the dielectric film 12, and the surface of the first substrate 11 is shown. Is exposed.
The first substrate 11 in a state where the protective film 14 is formed is carried into the film forming chamber 50 for the absorption film, and the surface on which the protective film 14 is formed faces downward and is horizontally placed on the substrate holder 51. Hold.

  Reference numeral 63 in FIG. 6B indicates a portion that becomes a square ring-shaped gap between the sealing material 31 and the dielectric film 12 described above, and a quadrangle passing through the center in the width direction of the gap 63 is described above. The arrangement axes Ha to Hd are equal in shape and size to the quadrangle.

  An alignment device (not shown) is connected to the substrate holder 51. By the alignment device, a quadrangle passing through the center in the width direction of the gap 63 is positioned vertically above the quadrangle of the arrangement axes Ha to Hd. When alignment is performed so that the vertices coincide with each other, the openings 57a to 57d face the square ring-shaped gap 63, and the discharge ports 67a to 67d also form square ring-shaped gaps via the openings 57a to 57d. It faces 63.

  The vapor deposition material 68 accommodated in each of the vapor deposition containers 61a to 61d contains at least one kind of active metal among Ba, Ca, and Sr. When heated, the active metal vapor is discharged from the discharge ports 67a to 67d, the vapor that has passed through the openings 57a to 57d reaches the portion of the square ring-shaped gap 63 on the surface of the first substrate 11, A thin film of active metal grows on the part.

  At this time, the edge portion outside the square ring-shaped gap 63 of the first substrate 11 and the portion where the dielectric film 12 is formed are covered with the mask 55. Then, no active metal thin film is formed on the surface of the protective film 14 on the dielectric film 12. Therefore, an absorption film is formed on the surface of the first substrate 11 in the portion of the square ring-shaped gap 63 (FIG. 6C).

  Here, the distance between the openings 57a to 57d adjacent to each other at the apexes of the squares of the arrangement axes Ha to Hd is short, and the vapor that has passed through the openings 57a to 57d spreads until reaching the first substrate 11, so that the absorption film 35 is integrated at the corner of the square ring-shaped gap 63, and the absorption film 35 forms a square ring shape surrounding the dielectric film 12. However, the absorption film 35 does not have a ring shape and may be cut off. .

The film forming chamber 50 for the absorption film is connected to the transfer chamber 45, and in addition to the film forming chamber 50, the stock chamber 43, the carry-out chamber 48, and the bonding chamber 44 are connected to the transfer chamber 45. Yes.
A vacuum exhaust system 19 is connected to the transfer chamber 45, the stock chamber 43, the carry-out chamber 48, and the bonding chamber 44, and the transfer chamber 45, the stock chamber 43, and the discharge chamber 48 are bonded by the vacuum exhaust system 19. Each chamber 44 is evacuated.

  FIG. 7 shows the second substrate 21 in a state where the address electrodes 25, the barrier ribs 23, the phosphor layers 22R, 22G, and 22B are formed on the surface, and the ring-shaped adhesive 38 is disposed on the edge portion of the surface. A plurality of the second substrates 21 in this state are stored in the stock chamber 43.

  A transfer robot (not shown) is arranged in the transfer chamber 45, and the first substrate 21 in which the absorption film 35 is formed is obtained by taking out the second substrate 21 from the stock chamber 43 and carrying it into the bonding chamber 44. The substrate 11 is taken out from the film formation chamber 50 and carried into the bonding chamber 44, the vacuum valve 39 is closed, and the bonding chamber 44 is shut off from the transfer chamber 45.

An alignment device (not shown) is arranged inside the bonding chamber 44, and the surface on which the absorption film 35 of the first substrate 11 is formed and the surface on the side on which the adhesive 38 of the second substrate 21 is disposed. And the first and second substrates 11 and 21 are aligned.
As described above, the absorption film 35 is not formed on the edge portion of the first substrate 11, the surface of the first substrate 11 is exposed, and the adhesive 38 and the first substrate are aligned in the aligned state. 11 edge portions face each other.

When the height of the adhesive 38 is higher than that of the partition wall 23 and the first and second substrates 11 and 21 are brought close to each other in the aligned state and the partition wall 23 is brought into contact with the protective film 14, the adhesive 38 is The first and second substrates 11 and 21 are adhered to the surface of the first substrate 11 with an adhesive 38.
A gas purifier 46 is connected to the bonding chamber 44 via a pipe 47.

  After the bonding chamber 44 is cut off from the transfer chamber 45, at least before the first and second substrates 11 and 21 are bonded together, the gas purifier 46 or a gas introduction system (not shown) supplies Xe to the bonding chamber 44. A discharge gas containing one or both of gas and Ne gas is introduced to form a bonding atmosphere that is substantially equal to the gas pressure (for example, 60 kPa) sealed in the plasma display panel 2 after the gas pressure is completed.

  Since the first and second substrates 11 and 21 are bonded in the bonding atmosphere, a predetermined space is formed in the space surrounded by the adhesive 38 in the gap between the first and second substrates 11 and 21. Pressure discharge gas is enclosed.

  After the first and second substrates 11 and 21 are bonded, a discharge gas is introduced into the bonding chamber 44 from the gas purifier 46 or the gas introduction system, and the pressure in the bonding chamber 44 is reduced to near atmospheric pressure. The distance between the first and second substrates 11 and 21 is made uniform by the pressure difference between the pressure in the gap between the first and second substrates 11 and 21 and the pressure in the bonding chamber 44.

  A light source (not shown) is disposed in the bonding chamber 44. As described above, since the first substrate 11 is transparent, when ultraviolet rays are irradiated from the light source toward the back surface of the first substrate 11, the ultraviolet rays pass through the first substrate 11 and enter the adhesive 38.

The adhesive 38 contains an ultraviolet curable resin. When ultraviolet rays are incident, the ultraviolet curable resin is polymerized, and the adhesive 38 is cured in a state of being in close contact with the first and second substrates 11 and 21. A sealing material 31 made of the cured product is formed.
After the sealing material 31 is cured, the discharge gas is collected from the bonding chamber 44 to the gas purifier 46, and the discharge gas is removed from the bonding chamber 44 to form a reduced pressure atmosphere.

  When the adhesive 38 is cured, an impurity gas such as water or alcohol is generated inside the bonding chamber 44 due to the polymerization reaction of the ultraviolet curable resin. The absorption film 35 described above is disposed in the space surrounded by the adhesive 38, and the impurity gas released from the adhesive 38 into the gap between the first and second substrates 11, 21 is the absorption film 35. Therefore, the purity of the discharge gas sealed by the first and second substrates 11 and 21 does not decrease.

  When the adhesive 38 is cured, the impurity gas is also released into the bonding chamber 44. Therefore, the bonding chamber 44 is evacuated and the impurity gas is removed, and then the transfer chamber 45 and the bonding chamber 44 are connected. Then, the plasma display panel 2 in a state where the sealing material 31 is formed is transferred from the bonding chamber 44 to the carry-out chamber 48 through the transfer chamber 45, and the new first and second substrates 11 and 21 are transferred. The film forming chamber 50 and the stock chamber 43 are carried into the bonding chamber 44 through the transfer chamber 45, respectively.

  The gas purifier 46 is configured to remove the impurity gas from the recovered discharge gas, and after the new first and second substrates 11 and 21 are carried in and the bonding chamber 44 is shut off from the transfer chamber 45. Then, the discharge gas after removing the impurity gas is returned from the gas purifier 46 to the bonding chamber 45 to form the above-described bonding atmosphere. In this way, the discharge gas is reused for a plurality of times of bonding and is not wasted.

  The plasma display panel 2 carried out to the carry-out chamber 48 closes the vacuum valve 39 between the transfer chamber 45 and the carry-out chamber 48 and closes the door of the carry-out chamber 48 with the transfer chamber 45 shut off from the carry-out chamber 43. Open and take out to the outside (atmosphere).

By using this film forming apparatus 1, everything from the step of forming the protective film 14 to the step of bonding the first and second substrates 11 and 21 is performed in a reduced-pressure atmosphere. 21 is not exposed to the atmosphere. Therefore, no impurity gas (for example, water, oxygen, or N ₂ ) from the atmosphere enters between the first and second substrates 11 and 21, and the purity of the discharge gas is not lowered, and the plasma display panel 2 is caused to emit light. When the discharge voltage does not increase.

  Further, although the protective film 14 and the absorption film 35 have high impurity gas absorption, since the protective film 14 and the absorption film 35 are formed and sealed with the sealing material 31 without being exposed to the atmosphere, The protective film 14 and the absorption film 35 are not deteriorated.

  Although the material which comprises the protective film 14 is not specifically limited, It is desirable to use a metal oxide with high electron emission characteristics like MgO, CaO, and SrO. One kind of these metal oxides may be used alone for the protective film 14, or two or more kinds such as a mixture of SrO and CaO and a mixture of SrO and MgO may be used for the protective film 14. Good.

  The absorption film 35 of the plasma display panel 2 of the first example can use one or more kinds of active metals such as Sr, Ba, and Ca. The type of active metal constituting the absorption film 35 is not particularly limited, and materials other than metals can be used as long as they can absorb impurity gas.

  Although the ultraviolet curable resin used for the adhesive 38 is not particularly limited, specifically, it contains at least one kind of resin that is polymerized by ultraviolet irradiation such as an acrylic resin, an epoxy resin, or an unsaturated polyester resin.

  In addition to the ultraviolet curable resin, it is also possible to use a thermosetting resin that is polymerized by heating. In this case, the adhesive 38 is brought into contact with the first and second substrates 11 and 21. The adhesive 38 can be cured by heating in a heated state. Furthermore, in addition to the resin described above, additives such as a filler and a coupling agent are added to the adhesive 38 to form a sealing material 31 containing a resin and made of a resin material to which the additive is added. May be.

  The case where the protective film 14 is disposed only on the transparent electrode 15 has been described above, but the present invention is not limited to this, and the protective film 14 is formed on the metal electrode (address electrode) 25 in addition to the transparent electrode 15. You may arrange.

  The above describes the case where the first and second substrates 11 and 21 are bonded together after the adhesive 38 is formed on the surface of the second substrate 21, but the present invention is not limited to this, The first and second substrates 11 and 21 may be bonded together after the agent 38 is formed on the surface of the first substrate 11. In this case, the adhesive 38 is formed in close contact with one or both of the surface of the first substrate 11 and the surfaces of the absorption films 35 and 36.

  The adhesive 38 is not only attached to the surfaces of the first and second substrates 11 and 21 but also to other members on the surfaces of the first and second substrates 11 and 21 such as the absorption films 35 and 36 as described above. However, in consideration of the bonding strength after curing, a sealing material that is in direct contact with the first and second substrates 11 and 21 and directly in contact with both the first and second substrates 11 and 21. It is desirable to form 31.

The formation method of the protective film 14 and the absorption film 35 is not limited to the vapor deposition method, and can be formed by other film formation methods such as a sputtering method as long as the film can be formed in a reduced pressure atmosphere.
The shape of the dielectric film 12 is not limited to a quadrangle, and may be an ellipse or a true circle. Further, the ring shape of the sealing material 31 is not limited to the square ring shape, and may be an elliptical ring shape or a perfect circular ring shape.

  Accordingly, the shape of the gap 63 between the dielectric film 12 and the sealing material 31 is not limited to the rectangular ring shape, and may be a square ring shape, an elliptical ring shape, or a perfect circular ring shape.

  If the openings 57a to 57d of the mask 55 are arranged along the gap 63 between the dielectric film 12 and the sealing material 31, the shape and arrangement are not particularly limited. For example, the shape of the gap 63 is elliptical. In the case of a circle such as a circle or a perfect circle, the arrangement axes Ha to Hd of the openings 57 a to 57 d are also curved along the shape of the gap 63.

  A plurality of discharge ports 67a to 67d may be provided in one large vapor deposition vessel. Specifically, only one large vapor deposition vessel is provided vertically below the mask 55, and the vertical portions of the openings 57a to 57d of the large vapor deposition vessel. Discharge ports 67a to 67d may be provided below.

  However, when the vapor deposition container is enlarged, it takes time until the vapor release rate is stabilized. Therefore, the number of the vapor deposition containers 61a to 61d is plural, and one vapor deposition container 61a to 61d is provided on each of the four sides of the square on the mask 55. It is preferable to arrange two or more.

  When a plurality of vapor deposition containers 61a to 61d are installed, the same vapor deposition material may be accommodated in each of the vapor deposition containers 61a to 61d, or different vapor deposition materials may be accommodated so that the gap between the dielectric film 12 and the sealing material 31 is accommodated. An absorption film 35 made of a different vapor deposition material may be disposed on each side of 63.

  After using a mixed material in which SrO is added to CaO as a vapor deposition material, and forming a protective film 14 by forming a CaO film (thickness 800 nm) with 20 mol% of SrO added by EB vapor deposition, a vapor deposition material made of Ba Was used to form the absorption film 35.

  A discharge gas containing Ne as a main component and Xe added at 4% is introduced into the bonding chamber 44 to form a reduced pressure atmosphere having a total pressure of 400 Torr, and the first and second substrates 11 and 21 are bonded together, A plasma display panel 2 of the first example was obtained (Example).

Separately, after the protective film 14 is formed on the first substrate 11, the first and second substrates 11 and 21 are pasted using the same adhesive 38 as in the embodiment without forming the absorption film 35. In addition, a comparative plasma display panel was manufactured.
Note that both the examples and comparative examples were performed in a reduced-pressure atmosphere from the formation of the protective film 14 to the step of bonding the first and second substrates 11 and 21 and sealing the discharge gas in the atmosphere. .

<Discharge voltage measurement>
The plasma display panel 2 of the example and the plasma display panel of the comparative example were placed in a constant temperature and humidity chamber at a temperature of 85 ° C. and a humidity of 95%, and the change with time in the discharge voltage was measured. FIG. 8 shows the measurement results of the PDP 1 of the example, and FIG. 9 shows the measurement results of the plasma display panel of the comparative example.

  8 and 9, the horizontal axis indicates the aging time (unit: time), the vertical axis indicates the voltage, Vfn in FIGS. 8 and 9 indicates the maximum discharge start voltage (maximun firing voltage), and VsmN is The maximum sustain voltage is shown.

  As is apparent from FIGS. 8 and 9, the plasma display panel 2 of the example showed a slight increase in the discharge voltage after 2000 hours in both the sustain discharge and the write discharge, but the plasma display of the comparative example The discharge voltage of the panel increased with time. From the above, it was found that the discharge voltage of the plasma display panel 2 of the present invention is more stable than the conventional one.

  In addition, as for the plasma display panel 3 of the second example in which the protective film 14 is formed to the vicinity of the sealing material 31 and the absorption film 36 is configured, the discharge voltage is increased similarly to the plasma display panel 2 of the above example. There wasn't.

The perspective view of the display area of the plasma display panel of a 1st, 2nd example Cross section of the first example plasma display panel Sectional view of the plasma display panel of the second example The top view explaining an example of the film-forming apparatus of this invention (A): Plan view for explaining the positional relationship among the substrate, the mask, and the vapor deposition source, (b): sectional view taken along the line BB of FIG. 5 (a), (c): FIG. 5 (a). CC sectional view (A)-(c): Sectional drawing for demonstrating the process of forming a protective film and an absorption film Sectional drawing for demonstrating the 2nd board | substrate of the state by which the adhesive agent has been arrange | positioned The graph for demonstrating the relationship between the discharge voltage of the plasma display panel of an Example, and time. Graph for explaining relationship between discharge voltage and time of plasma display panel of comparative example

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Film-forming apparatus 2, 3 ... Plasma display panel 5 ... Display area 11 ... 1st board | substrate 12 ... Dielectric film 14 ... Protective film 15 ... Transparent electrode 21 ... 2nd board | substrate 31 ... Sealing material 35, 36 ... Absorbing film 38 ... Adhesive 50 ... Deposition chamber 55 ... Mask 57a to 57d ... Opening 60 ... Deposition source 61a to 61d ... Deposition container 67a to 67d ... ... Discharge port Ha ~ Hd …… Arrangement axis

Claims (4)

Manufacturing of a plasma display panel in which a first substrate and a second substrate are bonded together with a resin sealing material formed in a peripheral sealing region, and plasma is generated for each pixel in the display region. A method,
Forming an electrode on a surface of the first substrate facing the second substrate;
Forming a dielectric film in contact with the surface and side surfaces of the electrode;
A planar shape is larger than a planar shape of the dielectric film between the display region of the first substrate and the display region and the sealing region in a reduced pressure atmosphere, and an edge portion extends from the outer periphery of the dielectric film. Forming a protective film so as to protrude;
In a state where the reduced pressure atmosphere is maintained, the step of transporting the first and second substrates to the bonding chamber;
Filling the discharge chamber with a discharge gas;
Bonding the first and second substrates in the bonding chamber;
Further introducing a discharge gas into the laminating chamber to increase the pressure and bringing the protective film into contact with the partition walls of the second substrate;
Curing the sealing material of the resin;
A method for manufacturing a plasma display panel, wherein the protective film is sealed without being exposed to the atmosphere. The protective layer, MgO and, CaO and method of manufacturing a plasma display panel of claim 1 further comprising at least one metal oxide selected from the group consisting of SrO. After the step of bonding the first and second substrates in the bonding chamber,
The manufacturing method of the plasma display panel of any one of Claim 1 or Claim 2 which has the process of collect | recovering the discharge gas in the said bonding chamber. The resin is an ultraviolet curable resin,
The method for manufacturing a plasma display panel according to any one of claims 1 to 3 comprising the step of irradiating ultraviolet rays to cure the sealing material of the resin.

Images