KR100871095B1 - Glass and ceramic compositions for information display - Google Patents

Abstract

A ceramic composite composition for display is provided to reduce the power consumption of the display, to solve the problem of the TCP damage and to improve the luminance of the display by using high reflective and low dielectric constant calcium carbonate filler. A ceramic composite composition for display comprises 70-90 wt% of oxide mixture containing at least one of bismuth(Bi), zinc(Zn) and boron(B); and 10-30 wt% of calcium carbonate filler. The calcium carbonate filler has the dielectric constant more than 0 and less than 6, a firing temperature of 250 - 600 deg.C and the average particle diameter of 0.5 - 3 micrometer.

Description

Ceramic composite composition for information display

The present invention relates to a ceramic composite composition that can be applied to a display, and more particularly, to a ceramic composite composition for a display composed of a lead-free oxide-based mixture and a high reflectance and low dielectric constant calcium carbonate filler.

Liquid crystal displays (hereinafter referred to as "LCDs") are light-receiving elements themselves and cannot be used in the absence of light. Therefore, in order to be able to use the LCD even in the absence of light, a backlight unit as shown in FIG. 1A is applied to the rear of the LCD.

The BLU 100 is formed of a fluorescent lamp or a plane light having uniform brightness, and includes an upper and lower cases 110 and 120, an optical sheet 130, an inverter 140, and a surface light source device 150.

In addition, the inside of the surface light source device 150 is composed of a front substrate 160 and a rear substrate 170, as shown in Figure 1b, the rear substrate is formed with a reflective layer 172 to improve the light efficiency To increase the brightness of the display.

Conventional BLU reflector is mainly used by coating silver (Ag) on the surface of the base material composed of stainless steel (SUS), brass, aluminum (Al), polyethylene terephthalate (hereinafter referred to as 'PET') lamp Due to the yellowing problem of silver (Ag) due to the endothermic for a long time around the titanium oxide (TiO ₂ ) or a polymer layer having a high reflectance is used.

FIG. 2 is a perspective view of a plasma display panel, wherein a white dielectric 220 and a partition wall are present on a rear substrate 210 of a plasma display panel (hereinafter referred to as a 'PDP') 200 as shown in FIG. 2. In the case of the 230, high reflectance of visible light is required like the BLU of the LCD, and thus, when forming the white dielectric 220 and the partition 230, the PbO-based low-temperature baking glass, the ceramic filler for white expression, and the high reflectance are formed. A mixture comprising TiO ₂ with is applied.

However, the TiO ₂ applied to the LCD BLU reflector, the white dielectric of the PDP, and the barrier rib as described above is a metal oxide having a very high dielectric constant, and the capacitance and address-holding electrode between the address-address electrodes of the display To increase the capacitance of the liver. This phenomenon eventually leads to an increase in the discharge current of the address electrode during discharge, thereby increasing the heat generation of the driver IC package, particularly the Tape Carrier Package (hereinafter, referred to as 'TCP'), resulting in damage to TCP. It is a problem. In addition, since TiO ₂ is very expensive, it also causes the price of the display to increase.

In addition, the polymer having a high reflectance is weak to heat, and there is a risk of damage due to heat applied to the manufacturing process of the display, and there is a problem that the application field is very limited depending on the use of the display due to its low rigidity.

Accordingly, an object of the present invention is to provide a ceramic composite composition for a display including a new filler that can replace a conventional high reflectance material (Ag, TiO ₂ and a high reflectance polymer).

Another object of the present invention is to provide a ceramic composite composition for a display including a calcium carbonate (CaCO ₃ ) filler which is inexpensive and satisfies both high reflectivity and low dielectric constant as a new filler.

Another object of the present invention is to provide a ceramic composite composition for a display configured to include a lead-free oxide-based mixture and a calcium carbonate filler that does not cause environmental pollution problems.

The object of the present invention is bismuth oxide (Bi ₂ O ₃ ), zinc oxide-boron oxide (ZnO-B ₂ O ₃ ), zinc oxide-silicon oxide (ZnO-SiO ₂ ), zinc oxide-boron oxide- Silicon Oxide (ZnO-B ₂ O ₃ -SiO ₂ ), Zinc Oxide-Boron Oxide-Silicon Oxide-Aluminum Oxide (ZnO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), Bismuth Oxide-Silicon Oxide (Bi ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide-aluminum oxide type (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), bismuth oxide-zinc oxide-boron oxide-oxidation silicon-based _{(Bi 2 O 3 -ZnO-B} 2 O 3 -SiO 2), bismuth oxide-aluminum oxide-based _{(Bi 2 O 3 -ZnO-B} 2 O 3 -SiO 2 - zinc oxide - boron oxide - silicon oxide - Al ₂ O ₃ ), zinc oxide-boron oxide-aluminum oxide-silicon oxide-phosphorus oxide (ZnO-B ₂ O ₃ -Al ₂ O ₃ -SiO ₂ -P ₂ O ₅ ) and zinc oxide-barium oxide-boron oxide -Bis oxide Oxide containing at least one selected from the group consisting of mousse-silicon oxide-aluminum oxide-phosphorus oxide (ZnO-BaO-B ₂ O3-Bi ₂ O ₃ -SiO ₂ -Al ₂ O3-P ₂ O ₅ ) 70 to 90 wt% of the system mixture; And it is achieved by a ceramic composite composition for a display comprising 10 to 30wt% calcium carbonate filler.

In this case, the calcium carbonate filler has a dielectric constant of more than 0 and 6 or less, and has a firing temperature of 250 to 600 ° C. And calcium carbonate filler has an average particle diameter of 0.5-3 micrometers.

The oxide mixture is selected from the group consisting of sodium oxide (Na ₂ O), lithium oxide (Li ₂ O), potassium oxide (K ₂ O), vanadium oxide (V ₂ O ₅ ), and copper oxide (CuO). It may further comprise at least one metal oxide.

At this time, the oxide-based mixture preferably has a glass softening temperature of 250 to 600 ℃.

Therefore, the ceramic composite composition for a display according to the present invention is configured to include a low-cost calcium carbonate filler while satisfying both high reflectivity and low dielectric constant characteristics, thereby reducing power consumption of the display and solving the problem of TCP breakage. It works.

In addition, the calcium carbonate filler used in the ceramic composite composition for a display according to the present invention has a low firing temperature, so that a low temperature process (low temperature firing) is possible, and thus there is an advantage not limited to the application field.

In addition, since the ceramic composite composition for display according to the present invention comprises a lead-free oxide-based mixture and calcium carbonate filler, is harmless to the human body, there is an effect that can solve the environmental pollution problem when disposed.

The calcium carbonate filler included in the ceramic composite composition for a display according to the present invention exhibits a higher reflectance than a conventional reflective material (TiO ₂ ), thereby improving the brightness of the display.

The terms or words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a ceramic composite composition for display, and more particularly, at least one of bismuth (Bi), zinc (Zn), and boron (B) as a glass composition for forming a BLU of a LCD, a white dielectric of a PDP, and a partition wall. It is configured to include 70 to 90wt% of the oxide-based mixture including any one or more and 10 to 30wt% of the calcium carbonate filler.

At this time, the oxide-based mixture applied in the present invention is specifically bismuth oxide (Bi ₂ O ₃ ), zinc oxide-boron oxide (ZnO-B ₂ O ₃ ), zinc oxide-silicon oxide (ZnO-SiO ₂ ), zinc oxide - boron oxide - silicon oxide _{(ZnO-B 2 O 3 -SiO} 2), zinc oxide-boron oxide-silicon oxide-aluminum oxide-based _{(ZnO-B 2 O 3 -SiO} 2 -Al 2 O 3), Bismuth oxide-silicon oxide system (Bi ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide system (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide system ( Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide-aluminum oxide-based (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), bismuth oxide-oxidation Zinc-boron oxide-silicon oxide type (Bi ₂ O ₃ -ZnO-B ₂ O ₃ -SiO ₂ ), bismuth oxide-zinc oxide-boron oxide-silicon oxide-aluminum oxide type (Bi ₂ O ₃ -ZnO-B _{2 O 3 -SiO 2 -Al 2 O 3} ), zinc oxide-boron oxide-silicon oxide-aluminum oxide taking over _{(ZnO-B 2 O 3 -Al} 2 O 3 -SiO 2 -P 2 O 5) and acid Zinc-barium oxide-boron oxide-bismuth oxide-silicon oxide-aluminum oxide-phosphorus-oxide _{(ZnO-BaO-B 2 O3} -Bi 2 O 3 -SiO 2 -Al 2 O3-P 2 O 5) selected from the group consisting of It is preferably composed of at least one, and consists of sodium oxide (Na ₂ O), lithium oxide (Li ₂ O), potassium oxide (K ₂ O), vanadium oxide (V ₂ O ₅ ) and copper oxide (CuO) It may further include one or more metal oxides selected from the group.

Such an oxide-based mixture is a lead-free low melting point material, has a low glass softening temperature of 250 to 600 ° C., and does not contain harmful substances such as lead oxide (PbO), which does not cause environmental problems. .

The average diameter of the particles constituting the oxide mixture used in the present invention is 5 탆 or less, and preferably has a range of 0.1 to 1.0 탆.

The filler applied to the glass composition for plasma of the present invention uses a calcium carbonate (CaCO ₃ ) filler as a high reflectivity filler.

In this case, since the calcium carbonate filler exhibits a high reflectance and is inexpensive as compared with the conventional high reflectance material (Ag, TiO ₂ ), it is possible to obtain a better characteristic while replacing the conventional high reflectance material.

In addition, the calcium carbonate filler applied to the ceramic composite composition for display of the present invention has a low firing temperature of 250 to 600 ℃ there is an advantage that is not limited to the application field.

Hereinafter, the characteristics of the ceramic composite composition for a display according to the present invention will be described in detail with reference to the accompanying drawings and tables.

[Example]

One embodiment of the present invention relates to the particle size distribution of the calcium carbonate filler and the reflectance according to the content of the calcium carbonate filler contained in the ceramic composite composition for a display according to the present invention.

1. Method of Manufacturing Specimen

First, a specimen for measuring the change in reflectance according to the particle size distribution and calcium carbonate content of the calcium carbonate filler is prepared as follows.

The specimen is configured to include a calcium carbonate filler having a mean particle diameter of 0.5 μm, 1.0 μm and 2.0 to 3.0 μm and an oxide-based mixture of low melting point as shown in Table 1, wherein the content of the calcium carbonate filler is It consists of 10wt%, 20wt%, 30wt%.

The composition thus constituted is generally industrially used, such as a dry ball mill or a wet ball mill using a water or isopropyl alcohol, a vibration mill, a fractioner, a friction mill, a Henschel mixer, or the like. The mixing method is used for a certain period of time (about 24 hours).

Thereafter, the mixed composition and the organic material are mixed again in a proportion to prepare a paste.

At this time, the mixing ratio of the organic material is about 40wt% or less, and the organic material is a material that can be specifically applied to the manufacture of LCD BLU or PDP white dielectrics, barrier ribs, etc., for example, ethyl cellulose, hydroxy ethyl cellulose cellulose resins such as hydroxy ethyl cellulose, nitro cellulose, etc., acrylic resins such as polybutyl acrylate, polyisobuthyl methacrylate, It is configured to include one or more selected from the group consisting of vinyl alcohol (polyvinyl alcohol) resin, and mixed using a roll mill (roll mill).

The prepared paste is formed into a thick film on a glass substrate using a die-coater, leveled for a predetermined time, dried and subjected to a firing process.

At this time, as described above, the display ceramic composite composition according to the present invention is composed of a low melting point oxide-based mixture and a low temperature calcinable calcium carbonate filler and undergoes a low temperature baking process within a temperature range of 250 to 600 ° C.

Specifically, the paste prepared as described above is formed into a thick film on a glass substrate using a die coater, and flattened at room temperature for 5 to 30 minutes, followed by drying under an hour using an infrared (IR) dryer. In addition, the specimen is prepared by performing a calcination process at about 400 ° C. for 1 hour at an electric furnace (raising rate of 10 ° C./min) and at about 550 ° C. for 1 hour or less.

On the other hand, the specimen preparation for the comparative example is produced by the same process as the above-described embodiment, except that in the comparative example to apply a titanium oxide filler having a 0.5 ㎛ average particle diameter in place of the calcium carbonate filler.

2. How to measure

Specimens prepared as described above measure particle size distribution using a particle size analyzer and reflectance using an ultraviolet (UV) spectrum.

The particle size distribution was obtained using a particle size analyzer as shown in FIG. 3, and then transformed into a cumulative distribution to obtain a particle size distribution result for each specimen as shown in Table 1 below.

In addition, the measurement of the reflectance using the ultraviolet spectrum is performed at the UV wavelength of the 550 nm band.

3. Measurement result

Table 1 shows the change in reflectance according to the particle size distribution and calcium carbonate content of the calcium carbonate filler included in the display ceramic composite composition according to the present invention.

High Reflectivity Filler Psalter Particle Size Distribution (㎛) Reflectance according to content (%) d0.1 d0.5 d0.9 10wt% 20wt% 30wt% CaCO ₃ (Example) 0.5 μm 0.28 0.55 1.95 - 86 84 1.0 μm 0.43 0.75 2.08 72 82 79 2.0 ~ 3.0㎛ 0.54 1.01 2.12 80 83 79 TiO ₂ (Comparative) 0.5 μm 0.08 0.18 0.55 66 77 83

As shown in Table 1, the particle size distribution of the calcium carbonate filler included in the ceramic composite composition for display according to an embodiment of the present invention is present in the range of 0.04 to 6㎛, the average particle diameter is 0.5 to 3㎛ Have

In addition, when the calcium carbonate filler according to the present invention is included in 10 to 30wt%, has a reflectance value of at least equivalent to or more than titanium oxide filler, in particular, the measured reflectance value when the content of calcium carbonate filler is 20wt% When 20 wt% of titanium oxide filler is included, the reflectance is 5 to 9% higher than that of the measured reflectance.

That is, the calcium carbonate filler applied to the ceramic composite composition for a display according to the present invention may have a higher reflectance than when the titanium oxide filler is applied, thereby improving the brightness of the display to which the same is applied.

[Other Embodiments]

Another embodiment of the present invention relates to the electrical properties according to the content of the calcium carbonate filler contained in the ceramic composite composition for a display according to the present invention.

1. Method of Manufacturing Specimen

Specimen for measuring electrical properties according to the content of calcium carbonate filler are prepared as follows.

As shown in Table 2 below, the pellet was composed of only a calcium carbonate filler (100 wt%) having an average particle diameter of 0.5 μm, and a calcium carbonate filler having an average particle diameter of 0.5 μm in an oxide-based mixture frit (80 wt%). %) Is prepared as a pellet prepared by mixing, and as a specimen for the comparative example is prepared as a pellet prepared by mixing an oxide mixture frit (80wt%) with a titanium oxide filler (20wt%) having an average particle diameter of 0.5㎛. .

At this time, the oxide-based mixture frit may be applied to the oxide-based mixtures of the kind described above in one embodiment, in another embodiment of the present invention is applied to the boron oxide-zinc oxide (B ₂ O ₃ -ZnO) -based frit. . In addition, the mixture of the oxide mixture frit and the filler may use a tubular mixer.

The pellets prepared as described above are subjected to a firing process in a temperature range of 250 to 600 ° C., respectively, and then polished to prepare specimens for measuring dielectric constant.

According to another embodiment of the present invention, the firing process is performed at 550 ° C. for about 30 minutes, and the temperature increase rate is performed at 5 ° C./min, and the polishing is 10 mm or less in thickness and 10 mm to 56 mm in diameter. Prepare to size.

2. How to measure

Specimens prepared as described above are used to measure the permittivity of electrical properties.

The dielectric constant is measured through an LCR meter. After measuring Cp (Equivalent parallel capacitance) and D (Dissipation factor) at 1 MHz using a B-type electrode, the dielectric constant and Obtain the dielectric loss value.

3. Measurement result

Table 2 shows the dielectric constant (dielectric constant) and dielectric loss according to the content of the calcium carbonate filler included in the ceramic composite composition for display according to the present invention.

Classification Psalter Dielectric constant Dielectric loss Example CaCO ₃ 100wt% 4.75 ± 0.07 40.45 ± 3.59 Frit 80wt% + CaCO ₃ 20wt% 3.75 ± 0.06 76.22 ± 1.92 Comparative example Frit 80wt% + TiO ₂ 20wt% 10.82 ± 0.45 102.86 ± 4.36

As shown in Table 2, it can be seen that the calcium carbonate filler included in the ceramic composite composition for display according to the present invention has a significantly lower dielectric constant (dielectric constant) and dielectric loss than the conventionally applied titanium oxide filler. have.

That is, the calcium carbonate filler applied to the ceramic composite composition for a display according to the present invention is a metal oxide having a much lower dielectric constant than the conventional filler, so that the capacitance between electrodes of the display device can be lowered, thereby solving the problem of TCP breakdown. In addition, power consumption can be reduced to provide a low power display.

Therefore, the ceramic composite composition for a display according to the present invention can be easily applied to the display field, in particular, a field requiring low melting point, high reflectivity, low dielectric constant, such as a BLU, a white dielectric of a PDP, and a partition wall of an LCD.

The terms or words used in this specification and claims are not to be construed as being limited to their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

1A is a perspective view illustrating a liquid crystal display backlight unit;

1B is a cross-sectional view of the surface light source device shown in FIG. 1A;

2 is a perspective view illustrating a plasma display panel;

Figure 3 is a graph of particle size analysis results according to an embodiment of the present invention.

<< Explanation of symbols for main part of drawing >>

100: LCD BLU 110: Top case

120: lower case 130: optical sheet

140: inverter 150: surface light source device

160: front substrate 170: rear substrate

172: reflective layer 200: PDP panel

210: back substrate 220: white dielectric

230: bulkhead

Claims (7)

Bismuth oxide type (Bi ₂ O ₃ ), zinc oxide-boron oxide type (ZnO-B ₂ O ₃ ), zinc oxide-silicon oxide type (ZnO-SiO ₂ ), zinc oxide-boron oxide-silicon oxide type (ZnO- B ₂ O ₃ -SiO ₂ ), zinc oxide-boron oxide-silicon oxide-aluminum oxide type (ZnO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), bismuth oxide-silicon oxide type (Bi ₂ O _3- SiO ₂ ), bismuth oxide-boron oxide-silicon oxide based (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), bismuth oxide-boron oxide-silicon oxide based (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ ), Bismuth oxide-boron oxide-silicon oxide-aluminum oxide type (Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), bismuth oxide-zinc oxide-boron oxide-silicon oxide (Bi ₂ O ₃ -ZnO-B ₂ O ₃ -SiO ₂ ), bismuth oxide-zinc oxide-boron oxide-silicon oxide-aluminum oxide-based (Bi ₂ O ₃ -ZnO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ ), Zinc Oxide-Boron Oxide-Aluminum Oxide-Silicon Oxide-Phosphorus Oxide (ZnO-B ₂ O ₃ -Al ₂ O ₃ -SiO ₂ -P ₂ O ₅ ) and Zinc Oxide-Barium Oxide-Boron Oxide-Bismuth Oxide-Silicon Oxide Oxidized Egg Minyum-phosphorus-oxide _{(ZnO-BaO-B 2 O3} -Bi 2 O 3 -SiO 2 -Al 2 O3-P 2 O 5) the oxide mixture comprising at least one selected from the group consisting of 70 to 90wt% ; And Calcium Carbonate Filler 10-30wt% Ceramic composite composition for display comprising a. delete The method of claim 1, The calcium carbonate filler has a dielectric constant of greater than 0 and 6 or less. The method of claim 1, The calcium carbonate filler is a ceramic composite composition for a display having a firing temperature of 250 to 600 ℃. The method of claim 1, The oxide mixture is selected from the group consisting of sodium oxide (Na ₂ O), lithium oxide (Li ₂ O), potassium oxide (K ₂ O), vanadium oxide (V ₂ O ₅ ) and copper oxide (CuO). Ceramic composite composition for display further comprising at least a metal oxide. The method according to claim 3 or 4, The calcium carbonate filler has a ceramic composite composition for a display having an average particle diameter of 0.5 to 3㎛. The method of claim 5, wherein The oxide-based mixture is a display ceramic composite composition having a glass softening temperature of 250 to 600 ℃.

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