KR20090067831A - Environment friendly dielectric glass composition with titanium dioxide and its synthetic method - Google Patents

Abstract

A clear dielectric containing titanium oxide and a manufacture method thereof are provided to ensure high visible light transmission rate and low glass-transition temperature as well as proper dielectric constant without the use of lead and bismuth. A method for manufacturing a clear dielectric containing titanium oxide comprises the following steps of: mixing 8-40wt% of titanium oxide powder(TiO2), 15-50wt% of boron oxide powder(B2O3) and 8-40wt% of sodium oxide powder(Na2O); heat-treating and fusing the mixed powder to induce a chemical reaction; and cooling the fused material and making the material powder. In the mixing step, zinc oxide(ZnO) is additionally added. In the mixing step, silicon oxide(SiO2) is additionally added. The clear dielectric is used for plasma display panels.

Description

Environment friendly dielectric glass composition with titanium dioxide and its synthetic method

The present invention relates to a low melting lead-free transparent dielectric glass composition and a method for manufacturing the same. More specifically, a low melting lead-free transparent dielectric and a method for manufacturing the same, based on titanium oxide (TiO ₂ ), containing no lead harmful to humans and the environment It is about.

In the case of low melting transparent dielectric glass applied to PDP, it should be possible to fire at relatively low firing temperature of 540 ~ 580 ° C. Therefore, PbO- containing PbO- which has low melting point (PbO) as the main component for glass melting at low temperature B ₂ O ₃ based glass compositions are mainly used.

However, in recent years, it is required to remove lead components from glass materials from the viewpoint of environmental problems, and research has been actively conducted on compositions capable of replacing lead-containing materials in response to these requirements. Representative examples thereof include bismuth (Bi) based dielectric compositions and zinc (Zn) based dielectric compositions.

Korean Patent Publication No. 10-1999-0046605 discloses a dielectric composition composed of 50 to 85 wt% of PbO, 7 to 25 wt% of SiO _{2, and} 7 to 25 wt% of B ₂ O _3. In No. 10416, Bi ₂ O ₃ is 60-75 wt%, B ₂ O ₃ 4-15 wt%, SiO ₂ 5-8 wt%, P ₂ O ₅ 1-18 wt%, Al ₂ O ₃ 1-3 wt The technique regarding glass of the low melting lead-free composition which has% as a main component is introduced.

In addition, according to Japanese Patent Laid-Open No. 2000-226231, ZnO is 20 to 45% by weight, B ₂ O ₃ is 20 to 34% by weight, SiO ₂ is 20 to 45% by weight, and R ₂ O (K ₂ O, Na Lead-free glass compositions are characterized in that ₂ O and Li ₂ O) are 4-12 wt%, RO (sum of BaO and CaO) is 0-3 wt%, and NaF is 0.5-8 wt%. . In addition, U.S. Patent No. 6,417,123 has 20 to 45 wt% ZnO, 15 to 45 wt% BaO, 15 to 35 wt% B ₂ O ₃ , 3 to 15 wt% SiO ₂ , and PbO Introducing a glass composition of 0 to 24.5% by weight. All of the glass compositions provide glass compositions for use in PDP transparent dielectrics and partitioning agents.

Of these, bismuth (Bi) -based dielectric composition has a degree of difference, but it also causes environmental pollution, and more problematic is that the unit price is high. On the other hand, zinc (Zn) -based dielectric compositions are advantageous because they are free from environmental pollution and have a 50% price advantage over bismuth (Bi) -based dielectric compositions. There is a problem. In addition, there is a limit in lowering the firing temperature, but there is no choice but to use an alkali component in the composition. When the alkali component is used, a yellowing phenomenon occurs when the color changes to yellow after firing.

The present invention has been made to solve the above problems, it does not contain a heavy metal lead (Pb) or bismuth (Bi) harmful to the human body, high visible light transmittance, low vitrification temperature and low dielectric constant is appropriate It is an object to provide a melting point dielectric and a method of manufacturing the same.

Environment-friendly transparent dielectric of the present invention for achieving the above object comprises 8 to 40% by weight of titanium oxide (TiO ₂ ), the remainder containing boron oxide (B ₂ O ₃ ), sodium oxide (Na ₂ O) It is characterized by. The dielectric composition may further include zinc oxide (ZnO), and may further include silicon oxide (SiO ₂ ). The zinc oxide (ZnO) is 5 to 30% by weight, boron oxide (B ₂ O ₃ ) is 15 to 50% by weight, silicon oxide (SiO ₂ ) 10 to 15% by weight, sodium oxide (Na ₂ O) is 8 ~ 40%, silicon oxide (SiO ₂ ) It is characterized in that 10 to 15% by weight. The sodium oxide may be replaced with sodium carbonate (Na ₂ CO ₃ ). Eco-friendly transparent dielectric material according to the invention is characterized in that it is used in a plasma display panel transparent dielectric film.

Method for producing an environmentally friendly transparent dielectric according to the present invention comprises the steps of mixing titanium oxide (TiO ₂ ) 8 to 40% by weight, the rest of boron oxide (B ₂ O ₃ ), sodium oxide (Na ₂ O) in the form of a powder; Heat treating the mixed powder to perform melting and chemical reaction; After cooling the melt is characterized in that it comprises a step of producing a powder through a grinding process.

The dielectric composition may further include zinc oxide (ZnO), and may further include silicon oxide (SiO ₂ ). The raw material in the mixing step is 5-30% by weight of zinc oxide (ZnO), 15-50% by weight of boron oxide (B ₂ O ₃ ), 10-15% by weight of silicon oxide (SiO ₂ ), sodium oxide (Na ₂ O) is characterized in that 8 to 40%, silicon oxide (SiO ₂ ) 10 to 15% by weight. In addition, the melting and the step of the chemical reaction is characterized in that carried out for 1 to 10 hours in the temperature range of 800 ~ 1500 ℃.

The dielectric glass according to the present invention does not contain lead metal (Pb) or bismuth (Bi), which is a heavy metal, has a high visible light transmittance, a low vitrification temperature, and an appropriate dielectric constant, and can be used as an environmentally friendly dielectric glass. In particular, it is suitable as a material for the top plate dielectric for PDP, and it can be used as an exterior glass of construction having a photocatalyst property because a large amount of TiO ₂ is contained.

Components of the environmentally friendly transparent dielectric of the present invention is characterized in that it comprises titanium oxide, boron oxide, sodium oxide. In addition, zinc oxide and silicon oxide may be further included. The composition is environmentally friendly because it does not contain lead or bismuth components, which are heavy metals. In addition, it has an improved characteristic compared to the characteristics of the conventional flexible dielectric, it has a feature capable of low-temperature firing. The dielectric constant of the composition is 8 ~ 13 and the vitrification transition temperature is 400 ~ 500 ℃.

Method for producing an environmentally friendly transparent dielectric composition according to the present invention is as follows. It is divided into a step of preparing a mixture by mixing the component powders constituting the glass, and a step of synthesizing the glass by heat-treating the mixture at 800 ~ 1400 ℃ to melt and cool.

The manufacturing method is advantageous in that the mass production is possible due to the low cost and simple process. The component used in the present invention is characterized in that the solid oxide comprises titanium oxide, zinc oxide, boron oxide, silicon oxide, and sodium oxide as the main raw materials. The sodium oxide may be replaced with sodium carbonate. Composition ratio of the raw material is preferably titanium oxide (TiO ₂₎ contains 8 to 40% by weight. In addition, the zinc oxide (ZnO) is 5 to 30% by weight, boron oxide (B ₂ O ₃ ) is 15 to 50% by weight, silicon oxide (SiO ₂ ) 10 to 15% by weight, sodium oxide (Na ₂ O) or Sodium carbonate (Na ₂ CO ₃ ) preferably contains 8 to 40%. The reason for limiting the titanium oxide to 8 to 40% is that a melting point of less than 8% by weight does not play a role as a transparent dielectric, and if it exceeds 40%, there is a problem in that it does not have transparency.

Balance in the above proportion to mix the raw powders. The mixed powder is mechanically pulverized and mixed by a ball milling method using zirconia balls. The pulverized mixture is heat-treated in a high temperature heat treatment furnace at 800 to 1500 ° C. for 1 to 10 hours to cool the molten material that has been completely melted and chemically reacted on a stainless steel plate having a thickness of 5 mm. The cooled melt is produced in the form of fine powder with a size of 1 to 5 μm through a grinding process in the same manner as the ball mill in the form of a plate glass.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. However, the invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents may be thorough and complete, and the technical spirit of the present invention may be sufficiently delivered to those skilled in the art.

EXAMPLES TiO ₂ -based Transparent Dielectric Compositions and Methods for Manufacturing the Same

Titanium oxide (TiO ₂ ), zinc oxide (ZnO), boron oxide (B ₂ O ₃ ), silicon oxide (SiO ₂ ) and sodium oxide (Na ₂ O) are mixed in a weight ratio as shown in Table 1, followed by mixing The mixture was placed in a platinum crucible and heated to 1200 ° C. in the air, and maintained at an hour before quenching. The dielectric constant and vitrification temperature of the prepared composition are shown in Table 1.

Table 1

<Test Example 1> Check the transparency

The photograph of the photograph of the dielectric glass manufactured by the composition of Example 1, 8 is shown in FIG. It was confirmed that it was colorless and transparent.

Test Example 2 Crystal Structure

The dielectric glass prepared in the composition of Example 1 was analyzed using an X-ray diffractometer and an electron microscope, and it was confirmed that both were amorphous structures. The results of X-ray diffraction analysis for Example 5 are shown in FIG. 2. . As shown in Figure 2 it could be confirmed that the amorphous state. In FIG. 2, a gentle peak at 20 ° or less indicates that an amorphous structure is well formed by forming a tetrahedral or octahead lock unit unit. In other words, the transparent dielectric glass according to the present invention has a pattern of typical amorphous glass in which tetrahedral basic units are irregularly arranged as a result of X-ray rotation analysis.

Test Example 3 Vitrification Temperature Measurement

The vitrification temperature of the dielectric glass prepared according to the present invention was measured using a thermal analysis equipment manufactured by Netzch, Germany. Thermal analysis conditions were measured with a temperature increase rate of 5 ℃ / min, a temperature range of 200 ~ 800 ℃. As a result of the measurement, the vitrification temperature was measured at 400 to 500 ° C. A thermal analysis graph for Example 8 is shown in FIG.

Test Example 4 Dielectric Constant Measurement

In order to measure the dielectric constant, the dielectric glass composition prepared by the present invention was prepared in the form of plate glass, and then the surface was smoothly polished and cut into a size of 10 × 10 × 5 mm. Firing for a minute constituted the electrode. Table 1 shows the measured dielectric constant values. It was found that the measured dielectric constants are suitable for PDP top dielectrics in the range of 8 ~ 13.

1 is a photograph of a transparent dielectric composed of the compositions of Examples 1 and 8 according to the present invention.

2 is an X-ray diffraction diagram of a transparent dielectric composed of the composition of Example 5 according to the present invention.

3 is a thermal analysis graph showing the vitrification transition temperature of the transparent dielectric composed of the composition of Example 8 according to the present invention.

Claims (11)

Tungsten oxide (TiO ₂ ) containing 8 to 40% by weight, the remainder is boron oxide (B ₂ O ₃ ), and an environmentally friendly transparent dielectric, characterized in that it comprises sodium oxide (Na ₂ O). The method of claim 1, Eco-friendly transparent dielectric further comprises zinc oxide (ZnO) The method of claim 2, Eco-friendly transparent dielectric further comprises silicon oxide (SiO ₂ ). The method of claim 3, The zinc oxide (ZnO) is 5 to 30% by weight, boron oxide (B ₂ O ₃ ) is 15 to 50% by weight, silicon oxide (SiO ₂ ) 10 to 15% by weight, sodium oxide (Na ₂ O) is 8 ~ Eco-friendly transparent dielectric, characterized in that 40%. The method of claim 1, An environmentally friendly transparent dielectric, which is used in a plasma display panel transparent dielectric film. Titanium oxide (TiO ₂ ) containing 8 to 40% by weight, the remainder containing zinc oxide (ZnO) and boron oxide (B ₂ O ₃ ), silicon oxide (SiO ₂ ), sodium carbonate (Na ₂ CO ₃ ) Eco-friendly transparent dielectric, characterized in that. Mixing 8 to 40 wt% of titanium oxide (TiO ₂ ) with the remainder of boron oxide (B ₂ O ₃ ) and sodium oxide (Na ₂ O) in powder form; Heat treating the mixed powder to perform melting and chemical reaction; And cooling the melt to prepare a powder through a grinding process. The method of claim 7, wherein Eco-friendly transparent dielectric manufacturing method characterized in that it further comprises zinc oxide (ZnO) in the mixing step. The method of claim 8, Eco-friendly transparent dielectric manufacturing method characterized in that it further comprises silicon oxide (SiO ₂ ) in the mixing step. The method of claim 9, The zinc oxide (ZnO) is 5 to 30% by weight, boron oxide (B ₂ O ₃ ) is 15 to 50% by weight, silicon oxide (SiO ₂ ) 10 to 15% by weight, sodium oxide (Na ₂ O) is 8 ~ Eco-friendly transparent dielectric manufacturing method, characterized in that 40%. The method of claim 7, wherein The melting and chemical reaction step is an environmentally friendly transparent dielectric manufacturing method, characterized in that performed for 1 to 10 hours at a temperature range of 800 ~ 1500 ℃.

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