KR100947957B1 - Plasma display panel and Manufacturing method thereof - Google Patents

Abstract

The present invention discloses a plasma display panel and a method of manufacturing the same.

The present invention forms a holding and scanning electrode on a glass substrate cut to a predetermined size, a front substrate for post-processing the cut surface of the glass substrate, and a partition and an address electrode on a glass substrate cut to a predetermined size, By constructing a panel having a rear substrate for post-processing the cut surface of the glass substrate, it is possible to prevent breakage of the panel that may occur during the post-process.

Description

Plasma display panel and manufacturing method thereof

1 is a plan view of a conventional single plasma display panel.

2 is a plan view of a conventional multi-plasma display panel.

3 is a process chart for explaining a manufacturing process of a conventional multi-plasma display panel.

4A and 4B are perspective views showing cracks generated on a cut surface of a glass substrate of a conventional panel.

5 is a process diagram for explaining a manufacturing process of a multi-plasma display panel according to a first embodiment of the present invention.

6 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a second embodiment of the present invention.

7 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a third embodiment of the present invention.

8 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a fourth embodiment of the present invention.

9 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a fifth embodiment of the present invention.

10 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a sixth embodiment of the present invention.

11A to 11C are process charts for coating treatment after etching of FIG. 10.

12A to 12C illustrate a cut, polished, and reinforced shape of a glass substrate.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel and a method of manufacturing the same. More particularly, the present invention relates to a plasma display panel, and more particularly, to a method of preventing panel breakage by reinforcing a cutting surface of a glass substrate of a seam region and an electrode lead-out portion of a plasma display panel.

In general, a plasma display panel (PDP) is an element that displays an image by light during plasma discharge for each unit cell.

These PDPs are lighter and simpler to manufacture than conventional CRTs (Cathod Ray Tubes), and are increasingly used as display panels for stock exchange boards, video conferencing displays, and large-screen wall-mounted TVs. to be.

1 is a plan view of a conventional single plasma display panel. The single plasma display panel of FIG. 1 has a structure in which a front substrate 10 having sustain and scan electrodes and a rear substrate 20 having an address electrode and a partition wall overlap and are encapsulated.                         

2 is a plan view of a conventional multi-plasma display panel. The multi-plasma display panel of FIG. 2 is formed by connecting the single plasma display panels 30, 40, 50, and 60 of FIG. 1 in the horizontal and vertical directions. At this time, the connecting portion between the panels 30, 40, 50, and 60 constituting the large screen becomes the core region 70, and the core region exists in the display region forming the large screen.

A manufacturing process of the conventional multi-plasma display panel will be described with reference to FIG. 3.

After cutting the glass substrate to a predetermined size, a front substrate is manufactured by forming a holding and scanning electrode on the cut glass substrate (S1), and forming a barrier rib and an address electrode on the other cut glass substrate on the rear surface. A substrate is prepared (S2).

The front panel and the rear substrate thus manufactured are overlapped and sealed in a sealed structure to manufacture a display panel (S3). The single panel thus produced is shown in FIG. 1. The display panels are connected and assembled to form a large screen (S4), and the large screen is illustrated in FIG. 2.

At this time, in the step S1, the cut surface of the glass substrate cut to a predetermined size has a defect, there is a problem that cracks and tears occur. To illustrate this problem, reference is made to FIGS. 4A and 4B. 4A illustrates a case where a crack occurs on a cut surface of the glass substrate, and FIG. 4B illustrates an enlarged view of a portion A where the crack occurs in FIG. 4A.

As described above, when the glass substrate is cut in the conventional multi-plasma display panel, cracks and tears are generated at the cut surfaces and the edges thereof, and thus the edge portions may be broken by a stopper or the like when moving to a later process. There is a problem that the edge portion is in contact with the FPC may cause a short phenomenon.

This problem also occurs in the cut surface of the glass substrate of the electrode lead-out.

In the case of the electrode lead-out unit, an FPC for inputting an electrical signal of a PCB substrate to a panel is thermocompressed, and then an aging process is performed. In particular, when there is a minute defect on the surface of the glass substrate of the electrode lead-out during the process of applying heat, such as thermocompression and aging process, the glass substrate is easily broken. Accordingly, there is a problem that the yield of PDP is lowered and the manufacturing cost is increased.

In addition, a so-called 'multi-facet' technique has been developed that forms a plurality of functional layers in a single large substrate and cuts them to manufacture a plurality of front and rear substrates. The above problem also occurs in the manufacturing method of the panel.

An object of the present invention for solving the above problems is to reduce the breakage of the panel by cutting, grinding, strengthening, and coating the cut surface of the glass substrate used in the plasma display panel.

The present invention for achieving the above object is to form a holding and scanning electrode on the glass substrate, the front substrate for strengthening the cutting surface of the glass substrate; And a rear substrate which forms a barrier rib and an address electrode on the glass substrate and reinforces the cut surface of the glass substrate, wherein the reinforcement treatment comprises dilute HF solution, dilute H ₂ SO _{4, and} sodium tetrafluoro. In a solution of sodium nitrate NaNO ₃ , a molten salt in sodium tetrafluoroborate NaBF ₄ , or a solution of potassium nitrate KNO ₃ in potassium tetrafluoroborate KBF ₄ It is characterized by etching using either.

In addition, the present invention comprises a first step of manufacturing a front substrate by forming a holding and scanning electrode on the glass substrate; A second step of manufacturing a rear substrate by forming a barrier rib and an address electrode on the glass substrate cut to a size corresponding to the front substrate; A third step of strengthening the cut surfaces of the front substrate and the rear substrate by polishing, etching, or coating; A fourth step of aligning the front substrate and the rear substrate with each other, sealing and exhausting the panel to form a panel; And a fifth step of cutting and polishing unnecessary portions generated by the adhesive on the outer side surfaces of the front substrate and the rear substrate for the sealing.

The above and other objects and features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

5 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a first embodiment of the present invention.

In the present invention, a step (S10) of manufacturing a front substrate and a step (S20) of manufacturing a rear substrate are performed separately. Each step (S10, S20), after cutting the glass substrate to a predetermined size to form a holding and scanning electrode on the cut glass substrate (S11, S21), and etching the cutting surface of the glass substrate to be described later And the step S12 and S22 using the method, the compressed layer forming method on the glass surface, and the chemical treatment method.

After aligning the reinforced front substrate and the rear substrate through each step (S10, S20), the panel is manufactured by applying a sealant to the sides of the front and rear substrates and sealing the exhaust (S30). Panels that have passed through the above-described steps are assembled with each other to form a large screen (S40).

An etching method, a compression layer forming method on a glass surface, and a chemical treatment method are used for the reinforcement treatment of the steps S12 and S22, and the respective reinforcement treatment methods will be described in detail below.

First, the etching method is a mixture of 50% or less of dilute HF solution, sulfuric acid H ₂ SO ₄ , sodium tetrafluoroborate NaBF ₄ and sodium nitrate NaNO ₃ , Or a mixture of potassium tetrafluoroborate KBF ₄ and potassium nitrate KNO ₃ . At this time, it is preferable to apply a conventional technique as an etching method.

In addition, the glass substrate may be strengthened by using an annealing method to produce an effect such as etching. The annealing method is a technique of increasing the glass strength by reducing the stress at the crack tip by blunting the crack tip. Particularly, the annealing method is commonly used as a frame polishing method. The frame polishing method uses torch to soften by heating the cut surface of the defective glass substrate to a temperature above the softening point, thereby reinforcing the strength of the glass substrate and blunting the sharp surface.

Second, the method of forming a compressed layer on the glass surface increases the strength of the glass substrate by forming a layer having a compressive stress on the surface of the glass substrate. As such a method for forming a layer having a compressive stress is a heat treatment method and a crystallization treatment method.

In the heat treatment method, the glass substrate is heated to a glass transition point or more, and then the surface of the glass substrate is cooled as quickly as possible in the region where the glass substrate is not damaged. In this case, the temperature at which the glass substrate is not broken varies depending on factors such as thickness, material, and shape of the glass substrate.

Air jets, liquid jets, and gas fluidized particulate matter are used to rapidly cool glass substrates.

Under the quenching conditions, the surface of the glass substrate is cooled faster than the inside of the glass substrate, and the surface temperature thereof falls below the glass transition temperature (Tg). As a result, the surface of the glass substrate acts as a rigid elastomer, and the inner temperature of the glass substrate is still higher than the surface, so that the shrinkage of the inner glass is subject to resistance by the surface, so that when the temperature difference reaches equilibrium, the surface is compressed. It is high and tensile stress is generated in the inner glass. This heat treatment method is preferably applied when the glass substrate having a thickness of 2mm or more.

On the other hand, the crystallization method is a method of generating a compressive stress on the surface of the glass substrate by generating a surface crystallization layer having a lower coefficient of thermal expansion than the inside. This surface texture purification method is a technique for strengthening the glass substrate by heating and then heat-treating in air to cool the glass substrate in air. That is, when the glass substrate is cooled below the surface crystallization temperature, the internal compression ratio of the glass substrate is higher than the surface compression ratio, thereby causing compression on the surface.

In this case, the crystallization method is applied to a glass substrate having a specific composition composed of lithium alumino-silicate or zinc alumino-silicate.

Thus, through the heat treatment method and the crystallization treatment method, the glass substrate is formed into a compressive layer having a compressive stress, and the compressive layer has a strength equal to the "breaking strength of the glass + the magnitude of the compressive stress", thereby compressing the strength of the glass substrate. It can be improved by the magnitude of the stress.

Third, the chemical treatment method keeps the glass substrate in the molten salt bath and increases the strength of the glass substrate by replacing small ions contained in the surface of the glass substrate with large ions. That is, when small ions on the surface of the glass substrate are replaced with large ions, the ion radius is increased to increase the volume, thereby increasing the strength of the glass substrate.

The molten salt bath used in the chemical treatment method is as follows.                     

Table 1 Chemical Treatment

Basic Glass Composition Molten salt bath Mechanism Difference in Ion Radius (nm) Volume change (㎛ ^-3 g ^-1 ) Maximum Inductive Compression Stress (MPa) Li ₂ O-Al ₂ O ₃ -SiO ₂ NaNO ₃ Na ⁺ ⇔Li ⁺ 0.02 90 620 Li ₂ O-Al ₂ O ₃ -SiO ₂ KNO ₃ K ⁺ ⇔Li ⁺ 0.055 310 2000 Li ₂ O-Al ₂ O ₃ -SiO ₂ RbNO ₃ Rb ⁺ ⇔Li ⁺ 0.071 440 2210 Li ₂ O-Al ₂ O ₃ -SiO ₂ CsNO ₃ Cs ⁺ ⇔Li ⁺ 0.087 665 3965 Na ₂ O-Al ₂ O ₃ -SiO ₂ KNO ₃ K ⁺ ⇔Li ⁺ 0.035 220 1450 MgO-Al ₂ O ₃ -SiO ₂ Li ₂ SO ₄ 2Li ⁺ ⇔Mg ⁺ - - -

As shown in Table 1, the molten salt bath comprises sodium nitrate NaNO ₃ , potassium nitrate KNO ₃ , ribidium nitrate RbNO ₃ , cesium nitrate CsNO ₃ , And lithium sulfate (Lithium sulfate) Li ₂ SO ₄ and the like, and chemical treatment using each molten salt bath according to the type of each glass substrate.

For example, when molten salt bath NaNO ₃ is used, sodium ion Na ⁺ is lithium ion Li ⁺ to Is substituted. At this time, substituted lithium ions Since Li ⁺ is 0.02 nm larger in ion radius than sodium ion Na ⁺ , the volume is increased by 90 μm ⁻³ g ⁻¹ . Therefore, the compressive stress is increased by 620 MPa, thereby increasing the strength of the glass substrate.

In this way, when the small ions on the surface of the glass substrate are replaced with the large ions, the glass structure expands. However, this expansion range is limited to the inside of the glass substrate. Accordingly, the surface of the glass substrate is in a compressed state, and the inside of the glass substrate is in a tensile stress that is balanced with the compressed state of the surface, thereby improving the strength of the glass substrate.

6 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a second embodiment of the present invention.

In the second embodiment of the present invention as in FIG. 5, a step (S50) of manufacturing a front substrate and a step (S60) of manufacturing a rear substrate are performed separately.

Each step (S50, S60), after cutting the glass substrate to a predetermined size to form a holding and scanning electrode on the cut glass substrate (S51, S61), and coating the cut surface of the glass substrate ( S52, S62). Thereafter, the panel manufacturing step (S70) and the large screen configuration step (S80) are the same as in FIG.

For the coating treatment of the steps (S52, S62), phenol resin (Phenol Resin), melamine resin (Melamine Resine), epoxy resin (Epoxy Resin), urea resin (Urea Resin), and water glass and the like. Here, the water glass is composed of a small amount of iron oxide Fe ₂ O ₃ and water of 10 to 30% in addition to Na 2 O.nSiO 2 (n = 2 to 4). At this time, since a resin material such as epoxy resin is hardly cured by itself during coating treatment, it is preferable to harden using a curing agent such as an amine resin.

7 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a third embodiment of the present invention.

In the third embodiment of the present invention as in FIG. 5, a step of manufacturing a front substrate (S90) and a step of manufacturing a rear substrate (S100) are performed separately.

Each step (S90, S100), after cutting the glass substrate to a predetermined size to form a holding and scanning electrode on the cut glass substrate (S91, S101), and the cut surface of the glass substrate to perform one of the reinforcement process Example is an etching process (S92, S102), and the step of coating the cut surface of the glass substrate (S93, S103). Thereafter, the manufacturing step S110 of the panel and the step S120 of constructing the large screen are the same processes as those of FIG. 5.

8 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a fourth embodiment of the present invention.

As in FIG. 5, in the fourth embodiment of the present invention, a step of manufacturing a front substrate (S130) and a step of manufacturing a rear substrate (S140) are performed separately.

Each step (S130, S140), the step of cutting the glass substrate to a predetermined size and forming a holding and scanning electrode on the cut glass substrate (S131, S141), and the cut surface of the glass substrate to be described later Figure 12a To cutting to the same shape as the embodiments of Figure 12c, or using a soft cloth, abrasive stone, polishing cloth (S132, S142) and the step of reinforcing the cut surface of the glass substrate (S133, S143) It includes. Thereafter, the manufacturing step (S150) of the panel and the configuration step (S160) of the large screen are the same processes as those of FIG.

9 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a fifth embodiment of the present invention.

In the fifth embodiment of FIG. 9, a process of manufacturing a front substrate (S170) and a process of manufacturing a rear substrate (S180) are performed separately as in FIG. 5.                     

Each step (S170, S180), cutting the glass substrate to a predetermined size to form a holding and scanning electrode on the cut glass substrate (S171, S181) and the cut surface of the glass substrate to be described later Figure 12a To cutting to the same shape as the embodiments of Figure 12c, or by using a soft cloth, abrasive stone, polishing cloth (S172, S182), and coating the cut surface of the glass substrate (S173, S183) It includes. Thereafter, the manufacturing step S190 of the panel and the step S200 of constructing the large screen are the same processes as those of FIG. 5.

10 is a flowchart illustrating a manufacturing process of a multi-plasma display panel according to a fifth embodiment of the present invention.

In the sixth embodiment of FIG. 10, a process of manufacturing a front substrate (S210) and a process of manufacturing a rear substrate (S220) are performed separately as in FIG. 5.

Each step (S210, S220), after cutting the glass substrate to a predetermined size to form a holding and scanning electrode on the cut glass substrate (S211, S221), and the cut surface of the glass substrate to be described later Figure 12a To cutting into the same shape as in the embodiments of FIG. 12C, or polishing using a soft cloth, abrasive stone, polishing cloth, etc. (S212, S222), and etching the cut surface of the glass substrate (S213, S223). And, the coating process includes (S214, S224). Thereafter, the manufacturing step S230 of the panel and the step S240 of constructing the large screen are the same processes as those of FIG. 5.

5 to 7, small cracks generated on the cut surface of the glass substrate can be solved only by reinforcement treatment or coating treatment. However, as shown in Figs. 8 to 10, the large cracks generated on the cut surface of the glass substrate are more effective if the reinforcement or coating treatment after cutting and polishing.

Although not shown elsewhere, the cut surface of the glass substrate may be cut and polished, and then the coating surface may be treated without reinforcement to increase the strength of the cut surface of the glass substrate.

11A to 11C are process charts for coating after etching treatment of FIGS. 7 and 10. FIG. 11A is a cross-sectional view of a cracked glass substrate, and FIG. 11B shows an example of blunting the crack tip by etching the cracked glass substrate of FIG. 11A, and FIG. 11C is an upper surface of the etching surface of the glass substrate of FIG. 11B. Shows an example in which a coating treatment is performed using epoxy, water glass, or the like.

12A to 12C illustrate embodiments of the cutting and polishing steps of FIGS. 8 to 10, wherein the glass substrate and the glass substrate of the electrode lead-out portion of the cut seam according to the present invention are cut and polished. A diagram for explaining.

FIG. 12A illustrates an embodiment of a shape in which panel breakage is prevented by cutting two upper and lower corner portions of the cut surface of the glass substrate to remove sharp portions.

FIG. 12B illustrates an embodiment in which a panel is prevented by removing sharp portions by grinding the upper and lower edge portions of the cut surface of the glass substrate using a twisted cloth, abrasive stone, abrasive cloth, and the like.

FIG. 12C illustrates an embodiment of a shape in which two upper and lower corner portions of the glass substrate cut surface are cut and polished, and the side ends are cut and polished by a predetermined width.                     

After cutting and polishing the glass substrate in the seam area and the glass substrate of the electrode lead-out portion, the glass substrate is cut and cracked by using the above-described reinforcement treatment method, or by coating. Microdefects can be removed. As a result, the glass substrate is further increased in strength so as not to be damaged by external thermal and mechanical shocks.

As described above, according to the present invention, by cutting, polishing, reinforcing, and coating the sharp cut surfaces of the glass substrates of the seam area and the electrode lead-out part, it is possible to prevent panel breakage that may occur during post-processing.

In addition, a preferred embodiment of the present invention is for the purpose of illustration, those skilled in the art will be able to various modifications, changes, substitutions and additions through the spirit and scope of the appended claims, such modifications and changes are the following claims It should be seen as belonging to a range.

Claims (19)

A front substrate forming a holding and scanning electrode on the glass substrate and reinforcing the cut surface of the glass substrate; And A plasma display panel comprising: a barrier plate and an address electrode formed on a glass substrate, and a rear substrate for reinforcing the cut surface of the glass substrate; The reinforcement treatment is a solution of sodium nitrate NaNO ₃ dissolved in dilute HF solution, dilute H ₂ SO _4, sodium tetrafluoroborate NaBF ₄ , or potassium tetrafluoroborate (Potassium). Tetrafluoroborate) Plasma display panel comprising etching using any one of the solution dissolved potassium nitrate KNO ₃ in KBF ₄ . delete delete delete delete delete delete delete delete delete delete delete A first step of forming a front substrate by forming a sustain and scan electrode on the glass substrate; A second step of manufacturing a rear substrate by forming a barrier rib and an address electrode on the glass substrate cut to a size corresponding to the front substrate; A third step of strengthening the cut surfaces of the front substrate and the rear substrate by polishing, etching, or coating; A fourth step of aligning the front substrate and the rear substrate with each other, sealing and exhausting the panel to form a panel; And And a fifth step of cutting and polishing unnecessary portions generated by the adhesive on the outer side surfaces of the front substrate and the rear substrate for sealing. delete delete delete The method of claim 13, wherein the third step, Cutting and polishing an edge of a cut surface of the glass substrate; And The cut and polished cut surfaces were dissolved in dilute HF solution, dilute H ₂ SO _4, sodium tetrafluoroborate NaBF ₄ , sodium nitrate NaNO ₃ as a molten salt, or potassium tetrafluoro. A plasma display panel manufacturing method comprising the step of strengthening by etching with any one of a solution of potassium nitrate KNO ₃ dissolved in bororate KBF ₄ . delete delete

Images