KR100694388B1 - A dielectric substance composition material and the same composition method to pdp - Google Patents

Abstract

A dielectric composition for lead-free PDP real panel is provided to have favorable dielectric property and acid resistance sufficient to produce a compartment layer of PDP, and to inhibit movement of Ag ions diffused from an address electrode to prevent yellowing of the compartment layer by eliminating lead ingredient from the composition. The composition comprises: 40 to 80wt.% of Bi2O3; 0.1 to 30wt.% of SiO2; 0.1 to 20wt.% of Al2O3; 0.1 to 5wt.% of at least one oxide selected from a group consisting of Li2O, Na2O, K2O; 0.1 to 5wt.% of at least one oxide selected from a group consisting of CuO, CoO, NiO, SeO2, CeO2, Sb2O3, Nd2O3, Al2O5 and V2O5. The dielectric material is formed by blending all of the constitutional ingredients, that is, the above listed oxides together, melting the blend at 1200 to 1350deg.C and changing the molten material into powder. The powdery composition has particle size ranging from 1 to 2 micrometers. The powdery composition is further treated by calcination at 500 to 600deg.C.

Description

A dielectric substance composition material and the same composition method to PDP

1 is a cross-sectional view illustrating a structure of a general PDP.

2A and 2B are views for explaining a manufacturing process of the PDP panel of the present invention.

* Description of the symbols for the main parts of the drawings *

1,11,111-Transparent glass substrate 2-ITO electrode

3,13,113-dielectric layer 4-protective film

12,112-address electrode (Ag pattern film)

14, bulkhead layer 15-fluorescent material

114a-First Bulkhead Layer 114b-Second Bulkhead Layer

115-Photoresist

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition of a backside dielectric material used for plasma display panels (PDP) and the like, and more particularly, to a composition and composition method of a backside dielectric material containing no lead (Pb) harmful to a human body.

In general, the PDP is configured as shown in FIG. 1 as an example.

The upper plate 1 has an indium tin oxide (ITO) electrode 2 connected to the bus electrode in a predetermined pattern, and a transparent dielectric layer 3 and a protective film 4 are formed to cover the ITO electrode.

Meanwhile, the lower electrode 11 has an address electrode 12 formed in a predetermined pattern, and the address electrode is covered by the rear dielectric layer 13. The barrier layer 14 is formed on the dielectric layer. Fluorescent material 15 is applied to each pixel area partitioned by the barrier layer, and plasma gas is injected into the sealed space area of each pixel.

The PDP configured as described above discharges plasma gas under control of a bus electrode connected to the ITO electrode of the upper plate 1 and a voltage applied to the address electrode 12 of the lower plate. The plasma gas collides with the fluorescent material 15 and the pixel region emits light.

In the PDP configured as described above, one example of the conventional dielectric material composition for the backplane is PbO, SiO ₂ , B ₂ O ₃ , Al ₂ O ₃ , ZnO, etc., as disclosed in Korean Patent Registration No. 10-0395594. It is known to have a main component, but because it contains a large amount of Pb (lead) components harmful to the human body when there is a chemical reaction with a solution such as acid or alkali when the product is disposed of, there is a problem of contaminating soil and water quality.

In addition, when the barrier ribs are formed by chemical etching, the barrier ribs are etched together, so that the address electrode cannot be protected, thereby increasing the resistance of the address electrode.

In addition, the conventional dielectric material does not suppress the movement of Ag ions diffused from the address electrode, and there is a problem in that the brightness of the PDP decreases due to a yellowing phenomenon caused by diffusion of Ag metal or the like at the interface between the barrier layer and the electrode.

The present invention has been made to solve the above problems,

By developing a low-melting back dielectric material that does not contain harmful lead components to humans or the environment, eco-friendly materials can be used, resistance to acids, and movement of Ag ions diffused from address electrodes can be suppressed. An object of the present invention is to provide a dielectric material composition for a back plate of a plasma display panel.

In order to achieve the above object, the dielectric material composition for the PDP backplane of the present invention is 40-80 wt% of Bi ₂ O _3, 0.1-30 wt% of B ₂ O ₃ , 0.1-20 wt% of SiO ₂ , Li ₂ O, Na ₂ O 0.1-5% by weight of at least one oxide selected from R ₂ O group (alkali group) consisting of K ₂ O, CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O _{5 It} characterized in that it comprises 0.1-5% by weight of at least one oxide selected from the group consisting of.

In addition, the composition of the dielectric material for the PDP backplane of the present invention is 40-80% by weight of Bi ₂ O _3, 0.1-30% by weight of B ₂ O ₃ , 0.1-20% by weight of SiO _2, 0.1-20 weight of Al ₂ O ₃ % And 0.1-5% by weight of at least one oxide selected from the group R ₂ O (alkaline group) consisting of Li ₂ O, Na ₂ O, and K ₂ O, CuO, CoO, NiO, SeO ₂ , CeO 0.1-5% by weight of one or more oxides selected from the group consisting of ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O ₅ , and melt-cooling the mixed composition Characterized by undergoing a first powdering process.

In addition, the mixed composition is characterized in that the melting is made at 1200-1350 ℃.

In addition, the primary powdered composition is made of an average particle size of 1-2mm size, the primary powdered composition is characterized in that the secondary powder is an average particle diameter of 1-2㎛.

In addition, the secondary powdered composition is characterized in that fired at a temperature of 500-600 ℃.

Example

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative example PbO (wt%) 0 0 0 0 0 0 0 61 Bi ₂ O ₃ (wt%) 61.8 66.6 69.8 76 80 60 62 0 SiO ₂ (wt%) 12 7 9 7 5 22 8 One B ₂ O ₃ (wt%) 14 19 11 9 10 10 32.6 30 Al ₂ O ₃ (wt%) 12 7 9 7 4 4.9 5 2 RO (wt%) [MgO + CaO + ZnO + SrO + BaO] 0 0 0 0 0 0 0 6 R ₂ O (wt%) [Li ₂ O + Na ₂ O + K ₂ O] 0.1 0.1 0.5 0 One 3 2 0 [CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O ₅ ] (wt%) 0.1 0.3 0.7 One 0.1 0.1 0.4 0 Before transition (℃) 490 445 450 420 401 485 - 435 Softening point (℃) 530 510 485 465 450 535 - 477 Coefficient of linear expansion 70 75 75 86 99 70 - 74 Crystallization presence (below 700 ℃) radish radish radish radish radish radish Phase separation radish Dielectric constant 12-13 13-14 15-16 17-18 18-19 12-13 - 13-14 Acid resistance (μm / min) 0.1 0.15 0.2 0.3 0.7 0.1 - 1.3 Gelation Good Good Good Good Good Good - Good Yellowing phenomenon radish radish radish radish radish radish - radish

Each of the seven sample samples at the mixing ratio of the composition shown in Table 1 was put into a platinum crucible and melted for about 1 hour to 1200-1350 ° C., and then cooled using a dry cooling method, and the disk mill (Disk Mill) ) Was first ground to an average particle diameter of 1mm-2mm.

In particular, the oxide of the R ₂ O group (alkali group) is sufficient if any one or more of the described oxides are included in the ratio composition, and Table 1 of the present example is described as the total weight ratio without describing the individual weight ratio of each oxide.

In addition, in the auxiliary composition of the group consisting of CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O ₅ , at least one is contained in a constant ratio composition. It is sufficient if included, and described in total weight ratio, not individual weight ratio as in R ₂ O group (alkali group).

Subsequently, the powder of the first milled composition was second milled using a jet mill, a ball mill, a bead mill, and the like to have an average particle diameter of about 1-2 μm.

Samples were prepared using the secondary pulverized powder, each having a structure used for a dielectric material for PDP in the process shown in FIGS. 2A and 2B.

Referring to FIGS. 2A and 2B, the composition of the PDP dielectric material and the manufacturing process thereof according to the present invention will be described in detail. First, silver (Ag) corresponding to an address electrode having a thickness of about 0.3 μm on the transparent glass substrate 111 is described. The dielectric layer was formed by forming a pattern film 112 and mixing ethylcellulose, which is one of the vehicle materials, in a weight ratio of 7: 3, respectively, to form a paste on each sample sample of secondary powder on the upper layer where the silver pattern film was formed. (113) was formed to a thickness of about 30㎛ and cured and then fired by applying a heat of about 560 ℃.

In the same manner, seven sample samples of the PDP dielectric material were prepared, and the dielectric material containing the conventional PbO component was prepared under the same conditions as the embodiment of the present invention in order to compare with the sample of the sample. .

Using each sample prepared as described above, the transition point (Tg), softening point (Ts), linear expansion coefficient, crystallization, dielectric constant, acid resistance, gelation, and yellowing of the dielectric material were shown in Table 1, respectively.

The transition point was recorded by measuring the temperature at which the transition (time to start the material movement) occurs while increasing the temperature to 800 ℃ at a temperature increase rate of 10 ℃ / min made of a dielectric material prepared as shown in Figure 2b, the softening point is The molten glass is made into a block and polished to a size of 3mm x 3mm x 19mm, and then the temperature is softened (at the point of transition from the solid phase to the liquid phase) while the temperature is raised to 500 ° C at a heating rate of 10 ° C / min. It was.

The coefficient of linear expansion measured the degree of expansion of the specimen between 50-350 ° C. while melting molten glass, grinding it to a size of 3 mm x 3 mm x 19 mm, and then raising the temperature to 500 ° C. at a temperature increase rate of 10 ° C./min. .

The crystallization is judged to be poor when it is crystallized at 700 ° C. or lower in the process of measuring the transition point and is good when crystallized at 700 ° C. or higher, and the acid resistance is 1 in the state in which the dielectric layer 113 of FIG. 2A is configured. After immersing in a solution of HCl and a concentration of 1% HNO ₃ for a certain time, the acid resistance was evaluated by calculating the difference between the thickness of the dielectric layer formed by the initial firing and the etched thickness. If the dielectric material is low in acid resistance, it is etched together with the partition during formation of the partition by etching, so that the address electrode 112 cannot be protected, thereby increasing the resistance of the address electrode.

Dielectric constant is formed in the thickness of about 30㎛ on the transparent glass substrate 111 and the address electrode 112 of the primary powder and the ethyl cellulose, which is one of the vehicle materials, in a weight ratio of 7: 3, respectively. And after curing by heating at about 560 ° C., an electrode for evaluation is further formed on the substrate having the dielectric layer 113 formed thereon, and the dielectric of the insulating layer between the address electrode 112 and the silver evaluation electrode is formed. The constant was measured. If the dielectric constant of the dielectric material is too large, the response speed becomes slow and the power consumption increases.

Gelation was recorded by leaving the primary powder and the ethyl cellulose-based vehicle at a weight (wt)% of 7: 3, respectively, for about 2 days to check whether a constant viscosity was maintained.

In addition, the yellowing phenomenon was recorded by cutting the dielectric material prepared as shown in Figure 2b to a size of 100mm x 50mm, and evaluated the degree of Diffusion of Ag (silver) metal electrode with a color limiter and compared with the color index.

As can be seen from the results of Table 1 experiments for the dielectric material of the present invention, as the content of Bi ₂ O ₃ increased, the transition point and softening point of the glass decreased, and the dielectric constant and coefficient of thermal expansion increased. If it is 40 wt% or less, the firing temperature is increased to produce micro grains. If it is 80 wt% or more, surface cracking or warping may occur due to an increase in the coefficient of thermal expansion. Preferably it is included in 50 to 70% by weight.

In addition, as the content of B ₂ O ₃ increases, the transition point and softening point of the glass are lowered. If the content is 30% by weight or more, powdery phases occur, which makes glass production difficult. Preferably contained in 0.1 to 25% by weight.

In addition, the lower the SiO ₂ content, the worse the acid resistance and the lower the transition point and softening point of the glass. If it is 20 weight% or more, a baking temperature will become high and a density will worsen. Preferably included in 0.1 to 15% by weight.

In addition, the RO group composed of MgO, CaO, ZnO, SrO, and BaO can obtain a dielectric constant reducing effect at a similar firing temperature by partially using Bi ₂ O ₃ , and preferably contained in an amount of 0.1 to 20% by weight, respectively. It is good.

In addition, the R ₂ O group composed of Li ₂ O, Na ₂ O, and K ₂ O lowers the firing temperature, but increases the crystallinity when it is 5% by weight or more. Preferably contained in 0.1 to 1% by weight.

In addition, the group consisting of CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O ₅ is a group of Ag ions that are transferred from the Ag electrode through a redox reaction. It serves to suppress yellowing due to colloidalization and to improve color of bismuth-based glass. Preferably contained in 0.1 to 1% by weight, respectively.

The dielectric material composition for the PDP backplane of the present invention is not only superior in quality compared to the dielectric material produced by the conventional dielectric material composition without containing lead, and in particular, does not contain lead, which is environmentally friendly. There is this. In addition, the dielectric material composition of the present invention has sufficient acid resistance to protect the address electrode during the formation of the partition wall, and the yellowing phenomenon can be remarkably lowered as compared with the structure manufactured by the conventional dielectric material composition.

Claims (5)

40-80 wt% Bi ₂ O _3, 0.1-30 wt% B ₂ O ₃ , 0.1-20 wt% SiO _2, 0.1-20 wt% Al ₂ O ₃ , Li ₂ O, Na ₂ O, K ₂ O 0.1-5% by weight of at least one oxide selected from the alkali group consisting of CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O _A dielectric material composition for a backplane of a PDP, comprising 0.1-5% by weight of at least one oxide selected from the group consisting of 5. 40-80 wt% Bi ₂ O _3, 0.1-30 wt% B ₂ O ₃ , 0.1-20 wt% SiO _2, 0.1-20 wt% Al ₂ O ₃ , Li ₂ O, Na ₂ O, K ₂ O 0.1-5% by weight of at least one oxide selected from the alkali group consisting of CuO, CoO, NiO, SeO ₂ , CeO ₂ , Sb ₂ O ₃ , Nd ₂ O ₃ , As ₂ O ₅ , V ₂ O mixing one or more kinds of oxide selected from the group consisting of _{0.1-5. 5%} by weight, of the PDP, characterized in that goes through the step of pulverization after melt cooling the mixed composition back panyong method genetic composition stays. The method of claim 2, Melting of the mixed composition is a dielectric material composition method for a back plate of the PDP, characterized in that made at 1200-1350 ℃. The method of claim 2, The powdered composition is a dielectric material composition method for a back plate of the PDP, characterized in that the average particle diameter is made of 1-2㎛. The method of claim 4, wherein The powdered composition is a dielectric material composition method for a backplane, characterized in that fired at a temperature of 500-600 ℃.

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