KR101046236B1 - Sealing element of a flat panel display panel and sealing element-exhaust pipe assembly including the same - Google Patents

Abstract

The present invention sealing device comprises sealing elements and this, in the flat panel display - A method for sealing between, and more particularly a plasma display panel (PDP) glass substrate and the exhaust pipe of about the exhaust pipe assembly, Bi ₂ O _3, BaO, SiO While solving the pollution problem by using lead-free glass frit containing ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , MgO, Fe ₂ O ₃ , Co ₃ O ₄ and NiO The present invention provides a sealing element that maintains excellent sealing properties and can be optimized for exhaust pipe connection.

Flat Panel Display, Plasma Display Panel, Sealing, Frit, Slurry, Firing, Exhaust Pipe

Description

SEALING DEVICE OF FLAT DISPLAY PANEL AND SEALING DEVICE-EXHAUST TUBE USING THE SAME

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing element of a flat panel display panel and a sealing element-exhaust pipe assembly including the same. More particularly, the characteristics of a device for sealing a glass substrate and an exhaust pipe during manufacturing of a flat panel display panel such as a plasma display panel (PDP) are described. It is about the technique to improve.

In general, a plasma display panel (PDP) is a flat panel display that uses light generated by discharged ultraviolet rays by making electrodes on two glass opposing surfaces and injecting a discharge gas therebetween.

Among the key technologies in the field of PDP, the development of sealing glass joining two glass facing surfaces, the development of components for sealing between the exhaust pipe and panel for injecting discharge gas or exhausting impurity gas inside the panel, etc. There is this.

Since airtightness must be maintained after the discharge gas is injected or discharged between the exhaust pipe and the panel, a low melting sealing glass frit used to join the glass facing surfaces is used.

Currently, glass frit for sealing with low melting point and low coefficient of thermal expansion is PbO-B ₂ O _{3 type} , PbO-B ₂ O ₃ -SiO _{2 type} , PbO-B ₂ O ₃ -SiO ₂ -ZnO type, PbO-B ₂ O Amorphous or crystalline based on a ₃ -ZnO system, a PbO-B ₂ O ₃ -V ₂ O ₅ system, or the like is used.

In addition, a typical conventional technique for sealing between the exhaust pipe and the panel using the low melting point sealing glass frit, PbO-B ₂ O ₃ -ZnO-based glass frit is mixed with an organic solvent and an organic binder paste (paste) It is common to use it after making it.

In other words, the paste is applied to a portion where the exhaust hole and the exhaust pipe formed at the edge of the panel contact each other, and then the exhaust hole and the exhaust pipe are joined to each other.

However, in the prior art, there is a problem in that the organic binder is not sufficiently burned and remains in the paste, and then bubbles are generated during firing and airtightness is lowered.

In addition, the residual organic binder and the MgO protective layer reacts with each other when the PDP panel is in contact with each other, resulting in a chemical change, which causes a problem in that the performance of the PDP is easily deteriorated to shorten the PDP life.

In the related art, since the paste has to be manually applied to the part where the exhaust hole and the exhaust pipe formed at the edge of the panel contact each other, there is a problem in that productivity is lowered.

In addition, most of the sealing composition for the sealing element currently uses a product containing lead, in this case, because the lead is eluted at the time of disposal may cause environmental pollution.

However, in the conventional case using a lead-free glass frit, there is a problem that it is difficult to form into granules of a slurry, and there is a problem that manufacturing is not easy, such as not determining an appropriate firing time. In addition, even when the product is formed, there is a problem of insufficient flexibility or poor transferability, and there is a problem in that it is not suitable as a sealing element due to poor surface smoothness and film thickness uniformity.

The present invention has been made to solve the conventional problems as described above, in the sealing of the panel and the exhaust pipe to prevent the occurrence of internal bubbles and deterioration of airtightness, and to solve the environmental pollution problem while easily manufacturing and applying a sealing element. It is an object of the present invention to provide a slurry composition for sealing elements of a flat panel display panel having an optimal lead-free composition.

The sealing element of the flat panel display panel according to the present invention is Bi ₂ O ₃ 75 to 85% by weight, BaO 0.5 to 4% by weight, SiO ₂ 0.01 to 2% by weight, B ₂ O ₃ 5 to 8% by weight, ZnO 7 to 13 Lead-free comprising 0.01 to 4.5% by weight, Al ₂ O ₃ or MgO 0.01 to 0.6% by weight, a single component of Fe ₂ O ₃ , Co ₃ O ₄ and NiO or the sum of two or more components A glass frit composition is provided and is provided with a 'L' shaped ring in which a jaw is present inside the cross section, and the outer edge of the ring is provided in a rounded shape.

Here, the glass transition temperature (Tg) of the glass frit is characterized in that 340 ~ 350 ℃, pyrolysis temperature (Td) is 370 ~ 380 ℃, the sealing element is characterized in that the density is 3 ~ 6 g / ㎠ It is done.

In addition, the sealing element-exhaust pipe assembly of the flat panel display panel according to the present invention is Bi ₂ O ₃ , BaO, SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , MgO, Fe ₂ O ₃ , Co ₃ O ₄ and It is provided with a lead-free glass frit composition including NiO, and is provided with an 'L' shaped ring in which a jaw is present inside the cross section, and an outer edge of the ring is provided in a rounded shape. And an exhaust pipe having a funnel-shaped flare coupled to the inner jaw of the sealing element and a tubule connected to the flare.

As described above, in the present invention, by removing the lead component from the conventional sealing device composition, it is possible to solve the environmental pollution problem, the glass frit Bi ₂ O ₃ , BaO, SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ By properly combining materials such as O ₃ , MgO, Fe ₂ O ₃ , Co ₃ O _4, and NiO, the properties of the sealing element can be improved, and the display manufacturing process can be more easily automated, thereby increasing the productivity of the display device. Provide the effect of improving.

Hereinafter, a sealing element of a flat panel display panel and a sealing element-exhaust pipe assembly including the same according to the present invention will be described in detail.

First, the present invention is Bi ₂ O ₃ 75 ~ 85% by weight, BaO 0.5 ~ 4% by weight, SiO ₂ 0.01 ~ 2% by weight, B ₂ O ₃ 5 ~ 8% by weight, ZnO 7 ~ 13% by weight, Al ₂ Provided is a glass frit comprising 0.01 to 0.6% by weight O ₃ or MgO, 0.01 to 4.5% by weight of a single component or a combination of two or more components of Fe ₂ O ₃ , Co ₃ O ₄ and NiO. At this time, the glass transition temperature (Tg) of the glass frit is preferably 340 ~ 350 ℃, pyrolysis temperature (Td) is preferably to be 370 ~ 380 ℃.

Here, Bi ₂ O ₃ serves as a main component of the sealing element to lower the thermal characteristics. If the content is less than 75% by weight, the glass transition temperature may exceed 350 ° C. If the content is more than 85% by weight, the glass composition may be unstable and crystallization may occur during sealing, resulting in insufficient adhesion. May occur.

BaO serves to stabilize the glass. If it is added less than 0.5% by weight may cause a problem that crystallization occurs during the sealing operation, when added in excess of 4% by weight may cause the problem of insufficient spreadability during the sealing operation due to the increase of the thermal properties and the coefficient of thermal expansion. Can be.

SiO ₂ serves as a glass mesh former to stabilize glass. When added in less than 0.01% by weight may cause a problem that crystallization is caused during the sealing operation, when added in excess of 2% by weight may cause a problem that the spreadability during the sealing operation due to the increase in the thermal properties.

B ₂ O ₃ is a glass network former and plays a role of stabilizing glass. If the content is less than 5% by weight, the composition of the glass may become unstable, causing devitrification in the quenching process of the melt. If the content is more than 8% by weight, the spreading property may be insufficient due to an increase in thermal properties. Problems may arise.

ZnO is a mesh modifier that lowers thermal properties and coefficient of thermal expansion. When added in less than 7% by weight, the thermal properties and the coefficient of thermal expansion is high, and when added in excess of 13% by weight may cause a problem that crystallization occurs during the sealing operation.

Al ₂ O ₃ or MgO serves to stabilize the glass. If it is added less than 0.01% by weight may cause a problem of crystallization during the sealing operation, if it is added in excess of 0.6% by weight may increase the thermal properties and coefficient of thermal expansion, or may cause a problem of crystallization during the sealing process have.

Fe ₂ O ₃ , Co ₃ O ₄ , NiO serves to implement the color of the frit. If a single component or two or more of the three components are added in less than 0.01% by weight, it is difficult to express the desired color, and when added in excess of 4.5% by weight, devitrification occurs during glass production or crystallization occurs during the sealing operation. The problem of high thermal characteristics may occur.

Each of the above components can be used independently, but by adding two or more components in combination, it is possible to implement a different color than when added independently.

The present invention manufactures a glass frit using the above-described composition, the characteristics of which are investigated as follows.

1 is a graph showing the thermal characteristics of the glass frit according to the present invention.

Referring to FIG. 1, it can be seen that the glass frit including the lead component is almost similar to the thermal properties, and the characteristics thereof can be summarized as shown in Table 1 below.

The coefficient of thermal expansion is 7.707 in the data, which translates into 77.07 in terms of × 10 ^-7 / ℃. The reason why lead-free CTE is higher than lead is due to limitations in Bi material properties, but this is a numerical change that is not a problem for practical applications.

TABLE 1

division Tg (占 폚) Td (℃) CTE (× 10 ^-7 ) (℃) Flexible (conventional) 344 371 71 Lead Free (Invention) 346 372 77.07

Next, a method of forming a silyl element using the glass frit according to the present invention described above is as follows.

2 is a flowchart illustrating a method of forming a sealing device according to the present invention.

Referring to Figure 2, 45 to 94.9% by weight of the glass frit as the lead-free organic frit, 5 to 50% by weight of the organic solvent to be a lead-free filler and 0.1 to 5.0% by weight of the organic binder (S100) by mixing (S100) To form (S110).

Here, the mixing of the glass frit with the organic solvent and the organic binder raw material is intended to facilitate the production of the sealing element by preparing a slurry having fluidity.

For the mass production of the sealing element automation of the process for forming the sealing element is essential, and for this it is advantageous to give the fluidity to the raw material, the process of forming the slurry composition is very important.

Here, toluene, acetate, alcohol, and the like are used as the organic solvent, and an acryl or cellulose is used as the organic binder. In this case, when the acrylic organic binder is used, a slurry closer to a spherical shape may be obtained than when the cellulose binder is used, and therefore, an acrylic organic binder or a cellulose binder may be appropriately selected and used according to the required form.

The slurry is prepared by adding all the above-described raw materials and then ball milling or mixing using a stirrer. Alternatively, the glass frit may be ball milled and wet-pulverized, and then, an organic solvent and an organic binder may be added and ball milled again to prepare a slurry.

Next, the prepared slurry is spray dried to form a granule (S120). In this case, the slurry may be mixed again by a corn-blending method. For example, the blending method may be performed at 5 to 50 rpm for 10 to 60 minutes.

The slurry thus obtained is used to form the shape of the desired sealing element (S130). At this time, since the molding process is automated, the moldability of the slurry is required to have a uniform value within an appropriate range. Factors affecting the moldability of the slurry include particle size and particle size distribution, and the tap density and the flow rate of the slurry may be properties indicating moldability.

The particle size of the slurry required to ensure proper moldability is approximately 50 ~ 450㎛ average particle diameter, the tap density of the slurry is 2 ~ 4 g / ㎠, the flow rate (40 ~ 60sec) It is preferable.

Next, the slurry is molded to form a desired molded body, and the molded body is heat treated (S140) to complete the sealing element (S150). Such a sealing element includes a flat panel display panel, and may be used as a sealing component used in various electromagnetic devices such as a heater or a glow discharge device.

Among them, during the process of manufacturing a flat panel display device including a PDP, in order to inject discharge gas into the panel or exhaust the impurity gas, an exhaust hole is formed at the edge of the panel and an exhaust pipe is attached to the exhaust hole to inject and exhaust the gas. There is a sealing element that performs this.

In the present invention, various sealing elements required for a flat panel display panel including a PDP will be described.

Particularly, in order to realize the shape of sealing between the panel and the exhaust pipe of the PDP, the mold is designed in consideration of the pressure transferability during compression molding. It is preferable to form the molded body so that dimensional accuracy can be secured.

As another molding method, an extrusion molding method may be used. In this case, the slurry composition (lead-free glass frit + organic solvent + organic binder) is kneaded without forming granules and then manufactured into a symmetrical product using an extrusion molding machine. can do. In addition, it may be used in the same manner as the adhesive tape to the portion to be produced by sealing the plate shape having the desired width and length.

Here, the molded body sealing between the panel and the exhaust pipe of the PDP may be made independent or positioned integrally between the display panel and the exhaust pipe.

One example of a stand-alone type is a ring, plate or disc type, and in the case of a ring type, it is preferable to manufacture an outer diameter of 3 to 20 mm.

Next, the molded body formed as mentioned above is heat-treated to complete a sealing element. At this time, it is preferable to heat-treat for 10 to 60 minutes at an appropriate heat treatment condition 300 ~ 500 ℃ of the molded article including the lead-free glass frit according to the present invention. Moreover, it is preferable to heat up at a speed | rate of 1-10 degreeC per minute, until heat processing temperature reaches 500 degreeC from 300 degreeC.

During the heat treatment under the above-mentioned conditions, the organic matter contained in the organic solvent or the organic binder is burned to remove organic residues that degrade the properties of the sealing element.

3 is a flowchart illustrating a method for forming an exhaust pipe according to the present invention.

Referring to FIG. 3, a process of cutting tubules having a straw shape (S10) is performed. Next, the process of glazing (S20) is performed on the edge portion of the customs, and the step (S30) of expanding the edge portion of the customs in a funnel form.

Next, to complete the exhaust pipe by performing an annealing process (S40), and washing and drying (S50). Next, a step (S60) of final inspection is carried out to see if leakage parts or cracks are formed in the exhaust pipe.

Next, as illustrated in FIGS. 2 and 3, the completed sealing element and the exhaust pipe are integrated, and the exhaust port of the display panel is sealed using the sealing element-exhaust pipe assembly thus formed.

4 and 5 are photographs showing the lead-free sealing element-exhaust pipe assembly according to the present invention.

Referring to Figures 4 and 5, it can be seen that the product is formed at approximately the same level as the flexible sealing element-exhaust pipe assembly. Conventional lead-free sealing element has a problem that is difficult to form a product because it is difficult to form into granules, by using the lead-free glass frit composition described in the present invention, it is possible to produce a finished product to a level almost equivalent to a general product.

In order to confirm that the product is equivalent to the conventional level, the adhesion strength test is carried out.

6 is a schematic view showing an experiment for measuring the adhesion strength of the sealing element according to the present invention.

FIG. 6 illustrates a method of attaching the sealing element 310 according to the present invention on an upper portion of the panel 300 and applying a shock using the vibrating pen 320 to measure a time until the sealing element 310 is detached. The results are shown in Table 2 below.

TABLE 2

division Measure Primary Secondary Flexible (conventional) 180 seconds 168 seconds Lead Free (Invention) 210 seconds 225 seconds

From the results in Table 2, it can be seen that the adhesion strength of the sealing element using the lead-free glass frit according to the present invention is better than that of the conventional flexible element.

Here, the lead-free glass frit according to the present invention generates a chemical reaction with the substrate. In other words, Bi is diffused to the substrate to increase the adhesion strength. At this time, the diffusion depth depends on the sealing temperature and the holding time.

Figure 7 is a photograph showing the Bi diffusion of the lead-free glass frit according to the present invention.

Figure 7 (a) is a lead-free glass frit according to the present invention is sealed to the substrate, Figure 7 (b) shows a case using a conventional lead-containing product for comparing the features of the present invention.

Sealing temperature was 480 ~ 500 ℃, after maintaining for 10 to 30 minutes, the interface between the sealing element and the substrate was analyzed by mapping (mapping) with EDX. As a result, in the case of the lead-free glass frit according to the present invention (FIG. 7 (a)), it can be confirmed that diffusion of about 10 μm occurred. In addition, in the case of the glass frit containing lead (Fig. 7 (b)) it can be confirmed that almost no diffusion occurs.

As described above, the lead-free sealing element according to the present invention has better characteristics than the conventional one, and it will be described below that they are directly applied to the PDP.

8 and 9 are a perspective view and a cross-sectional view showing a sealing element-exhaust pipe according to the present invention.

Referring to FIG. 8, a lead-free including Bi ₂ O ₃ , BaO, SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , MgO, Fe ₂ O ₃ , Co ₃ O _4, and NiO ) Is provided with a glass frit composition, the sealing element 430 is provided with a 'L' shaped ring in which the jaw is present in the cross section. At this time, the outer edge of the ring is provided in a rounded form, unlike the conventional flexible sealing element.

Next, a flare 420 of the funnel type exhaust pipe 400 coupled to the inside of the jaw is provided, and the tubule 410 is provided on the top thereof.

Referring to FIG. 9, there may be a difference in piping characteristics and adhesion depending on the height a and the diameter of the lower diameter b of the flare 420. ) Is preferably 0.8 to 1.4 mm, and the lower diameter (b) is preferably 9.72 to 10.60 mm.

Next, the diameter of the capillary 410 is preferably formed within 6mm. Therefore, the lower diameter (b) of the flare 420 is preferably formed to be 8 ~ 11mm than the diameter of the capillary 410. As described above, in the present invention, it is preferable that the lower flare diameter is formed to be 1.3 to 2.2 times larger than the capillary diameter. When the ratio of the lower diameter is less than 1.3, the sealing margin may be reduced, and when the ratio of the lower diameter is larger than 2.2 times, the amount of glass frit may be increased, thereby reducing the exhaust efficiency.

10 is a cross-sectional view showing the application of the sealing element-exhaust pipe assembly according to the present invention to a PDP panel.

Referring to FIG. 10, the sealing element-exhaust pipe assembly described with reference to FIG. 9 is precisely aligned with the exhaust port 520 of the PDP panel 500 to perform a sealing process. In this case, when the sealing element-exhaust pipe assembly is heated to 400 to 600 ° C. and calcined for 10 to 60 minutes, a densified high quality PDP and a flat panel display device can be manufactured.

Here, if the maximum diameter of the flare 420 is formed to be close to the diameter of the capillary 410 can further improve the sealing properties, by using the lead-free glass frit composition according to the present invention can form a more detailed ring-shaped sealing element This allows for higher quality PDPs and flat panel display devices.

11 is a cross-sectional view illustrating the application of the sealing element-exhaust pipe assembly to the PDP panel according to another embodiment of the present invention.

11 is a flare of the exhaust pipe 600 is formed to have the same diameter as the customs 610. Since the glazing process and the expansion process of the exhaust pipe manufacturing process described in FIG. 3 can be omitted, the PDP and the flat panel display manufacturing process can be shortened and the quality can be improved as described above.

This is possible as the sealing element 620 can be formed in more detail using the lead-free glass frit according to the present invention.

Therefore, by using the sealing element according to the present invention as described above, by removing the lead component, it is possible to solve the environmental pollution problem, and to improve the characteristics of the sealing element and to more easily automate the display manufacturing process, Productivity can be improved.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments, but may be modified in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

1 is a graph showing the thermal characteristics of the glass frit according to the present invention.

2 is a flow chart showing a method of forming a sealing element according to the present invention.

3 is a flow chart illustrating a method for forming an exhaust pipe according to the present invention.

4 and 5 are photographs showing the lead-free sealing element-exhaust pipe assembly according to the present invention.

6 is a schematic view showing an experiment for measuring the adhesion strength of the sealing element according to the present invention.

7 is a photograph showing Bi diffusion of the lead-free glass frit according to the present invention.

8 and 9 are a perspective view and a cross-sectional view showing a sealing element-exhaust pipe according to the present invention.

10 is a cross-sectional view showing the application of the sealing element-exhaust pipe assembly according to the present invention to a PDP panel.

11 is a cross-sectional view showing the application of the sealing element-exhaust pipe assembly to the PDP panel according to another embodiment of the present invention.

Claims (8)

Bi ₂ O ₃ 75-85 wt%, BaO 0.5-4 wt%, SiO ₂ 0.01-2 wt%, B ₂ O ₃ 5-8 wt%, ZnO 7-13 wt%, Al ₂ O ₃ or MgO 0.01- Equipped with a lead-free glass frit composition comprising 0.01 to 4.5% by weight of 0.6% by weight, a single component of Fe ₂ O ₃ , Co ₃ O ₄ and NiO or a sum of two or more components, the interior of the cross section Is provided with a 'L' shaped ring with a jaw, the outer edge of the ring is a sealing element of a flat panel display panel is provided in a rounded form. delete The method of claim 1, The glass transition temperature (Tg) of the glass frit is 340 ~ 350 ℃, pyrolysis temperature (Td) is a sealing element of the flat panel display panel, characterized in that. The method of claim 1, The sealing element is a sealing element of the flat panel display panel, characterized in that the density of 3 ~ 6 g / ㎠. Provided as a lead-free glass frit composition comprising Bi ₂ O ₃ , BaO, SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , MgO, Fe ₂ O ₃ , Co ₃ O ₄ and NiO Is provided with a 'L' shaped ring in which the jaw is present in the inside of the cross-section, the outer edge of the ring is provided with a rounded sealing element; And Sealing element-exhaust pipe assembly of the flat panel display panel including an exhaust pipe provided with a funnel-like flare coupled to the inner jaw of the sealing element and the tubules connected to the flare. The method of claim 5, Sealing element-exhaust pipe assembly of the flat panel display panel, characterized in that the maximum diameter of the flare is provided with a size 1.3 to 2.2 times the diameter of the customs. The method of claim 5, Sealing element-exhaust pipe assembly of the flat panel display panel characterized in that the height of the flare is provided with a size of 0.8 ~ 1.4 mm. The method of claim 5, Sealing element-exhaust pipe assembly of the flat panel display panel, characterized in that the lower diameter of the flare is provided with a size of 9.72 ~ 10.60mm.

Images