JP2000327370A - Partition wall-forming material and glass composition for plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject material containing neither PbO nor alkali metal component affecting human health and electronic parts, bakable at low temperatures, leading to preventing a glass substrate involving the material from deformation by using, as a constitutive component, glass powder of specific composition comprising BaO, ZnO, B2O3 and SiO2. SOLUTION: This material is obtained by using, as a constitutive component, glass powder having a softening point of about <=630 deg.C and a thermal expansion coefficient adaptable to glass substrate, comprising 5-40 (pref. about 10-30) wt.% of BaO, 20-55 (pref. about 30-50) wt.% of ZnO, 15-50 (pref. about 20-50 wt.% of B2O3 and 0-25 (pref. about 2-15) wt.% of SiO2. This composition thus obtained is bakable at <=600 deg.C, leading to preventing a glass substrate involving the material from deformation. A partition wall for plasma display panels is made by kneading about 50-95 wt.% of the above glass powder with about 5-50 wt.% of ceramic powder to form a paste or green sheet, which is then either applied to a specified place followed by drying, or subjected to hot pressure bonding thereto followed by baking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for forming a partition for a plasma display panel.

[0002]

2. Description of the Related Art A plasma display panel is a self-luminous type flat display, has excellent characteristics such as light weight and thinness, a wide viewing angle, and the like, and is capable of realizing a large screen. It is receiving attention as one of certain display devices.

[0003] A plasma display panel is generally provided with a front glass substrate and a rear glass substrate facing each other. In a space between these substrates, a large number of partition walls (barrier ribs and barriers) for separating a gas discharge portion are provided. ) Is formed. As a material for forming the partition, a material obtained by mixing glass powder and ceramic powder is widely used. This partition wall forming material needs to be able to be fired at 600 ° C. or lower in order to prevent deformation of the glass substrate.
Therefore, glass having a softening point of 630 ° C. or less is used for the glass powder.

[0004]

Generally, the softening point is 630.
C. or lower glass has Pb as a component for lowering the softening point.
O and alkali metal oxides are contained, and this kind of glass is also used for the glass powder used for the above-mentioned partition wall forming material.

However, the glass containing PbO has a problem of affecting the human body when producing glass powder and treating waste. Further, it is known that the alkali metal component has an adverse effect on electronic components, and as a material for a plasma display panel, a material containing as little alkali metal component as possible is preferred.

An object of the present invention is to provide a partition wall forming material and a glass composition for a plasma display panel which can be fired at a temperature of 600 ° C. or less without containing PbO and an alkali metal component.

[0007]

The present inventors have made various studies and found that even if PbO or alkali metal oxide was not used, the glass based on BaO, ZnO, and B ₂ O ₃ was softened. The present inventors have found that there is a composition range where the point is 630 ° C. or lower, and propose the present invention.

That is, the material for forming a partition wall for a plasma display panel according to the present invention comprises 5 to 40%
_{nO 20~55%, B 2 O 3} 15~50%, SiO 2
It is characterized by containing glass powder having a composition of 0 to 25% as a constituent.

Further, the glass composition for a barrier rib forming material of the present invention comprises 5 to 40% of BaO and 20 to 55 of ZnO in mol%.
_{%, B 2 O 3 15~50%} , and having a composition of SiO ₂ 0 to 25%.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A plasma display according to the present invention.
The material for forming the barrier ribs for the tunnel is BaO-ZnO-B. _TwoO_ThreeMoth of system
Contains lath powder as the main constituent. Glass of this system
Is B_TwoO_ThreeIs within the range of 50 mol% or less, the softening point is
There is a composition region where the temperature is 630 ° C. or lower. Also this area
, The coefficient of thermal expansion tends to be high,
Includes relatively large amount of thermal expansion agent suitable for glass substrate
Adjusted to numbers.

The reason why the glass powder composition is limited as described above will be described below.

BaO is a component for lowering the softening point, and its content is 5 to 40%, preferably 10 to 30%.
If the content of BaO is less than 5%, the effect is not sufficient, and
%, The coefficient of thermal expansion becomes high, which is not preferable because it becomes incompatible with that of the glass substrate.

ZnO is a component which lowers the softening point and lowers the coefficient of thermal expansion.
%, Preferably 30 to 50%. If the content of ZnO is less than 20%, the above effects cannot be obtained. If the content is more than 55%, crystals are precipitated in the glass and a dense sintered body cannot be obtained, which is not preferable.

B ₂ O ₃ is a component constituting the skeleton of glass, and its content is 15 to 50%, preferably 20 to 50%.
%. If B ₂ O ₃ is less than 15%, vitrification becomes difficult. On the other hand, if B ₂ O ₃ is more than 50%, the softening point is 63.
If it is fired at a temperature of 600 ° C. or less so that the temperature does not become 0 ° C. or less, a dense sintered body cannot be obtained, and the panel characteristics deteriorate.

SiO ₂ is a component forming a skeleton of glass, and its content is 0 to 25%, preferably 2 to 15%.
It is. If the content of SiO ₂ is more than 25%, the softening point is 630 ° C.
If it is fired at a temperature of 600 ° C. or less, a dense sintered body cannot be obtained, and the panel characteristics will be reduced.

In addition to the above components, other components can be added as long as the effects of the present invention are not impaired. For example, to improve water resistance and chemical resistance, MgO, Ca
Alkaline earth metal oxides such as O and SrO, Al ₂ O ₃ ,
ZrO ₂ , TiO ₂ and P ₂ O ₅ for glass stabilization
May be added. The addition amount of other components should be limited to 20 mol% or less, preferably 15 mol% or less.

The partition wall forming material for a plasma display panel of the present invention preferably contains a ceramic powder in addition to the above glass powder for the purpose of maintaining the shape. In this case, the mixing ratio is 50 to 95% by weight of glass powder, 5 to 50% by weight of ceramic powder, especially 60 to 90% by weight of glass powder.
% By weight and 10 to 40% by weight of ceramic powder. If the amount of the ceramic powder is more than 50%, the sinterability becomes insufficient and it is difficult to form a dense partition wall. If the amount is less than 5%, the shape maintaining effect is reduced. As the ceramic powder, for example, alumina, zirconia, zircon, titania, cordierite, mullite,
Silica, willemite, tin oxide, zinc oxide and the like can be used alone or in combination of two or more.

Next, a method for using the material for forming a partition wall for a plasma display panel of the present invention will be described. The material of the present invention can be used in the form of, for example, a paste or a green sheet.

When used in the form of a paste, together with the above-mentioned glass powder and, if necessary, ceramic powder,
Use thermoplastic resin, plasticizer, solvent, etc. The content of the glass powder and the ceramic powder in the paste is 3
It is generally about 0 to 90% by weight.

The thermoplastic resin increases the film strength after drying,
Further, it is a component that imparts flexibility, and its content is 0.1%.
It is generally about 1 to 20% by weight. As the thermoplastic resin, polybutyl methacrylate, polyvinyl butyral, polymethyl methacrylate, polyethyl methacrylate, ethyl cellulose and the like can be used, and these can be used alone or in combination.

The plasticizer is a component that controls the drying speed and imparts flexibility to the dried film. The content of the plasticizer is generally about 0 to 10% by weight. As the plasticizer, butylbenzyl phthalate, dioctyl phthalate, diisooctyl phthalate, dicapryl phthalate, dibutyl phthalate, and the like can be used, and these can be used alone or in combination.

The solvent is a material for making the material into a paste, and its content is generally about 10 to 30% by weight. Examples of the solvent include terpineol, diethylene glycol monobutyl ether acetate, 2,2,4
-Trimethyl-1,3-pentadiol monoisobutyrate or the like can be used alone or in combination.

The paste can be prepared by preparing a glass powder, a ceramic powder, a thermoplastic resin, a plasticizer, a solvent, and the like, and kneading them at a predetermined ratio to form a paste.

In order to form barrier ribs using such a paste, first, these pastes are applied by a screen printing method, a batch coating method, or the like, and a coating layer having a predetermined thickness is formed. Then, a resist film is formed, and exposed and developed. Subsequently, unnecessary portions are removed by using a sand blast method, followed by firing to obtain a partition having a predetermined shape.

When the material of the present invention is used in the form of a green sheet, a thermoplastic resin, a plasticizer and the like are used together with the glass powder and the ceramic powder.

The content of the glass powder and the ceramic filler in the green sheet is generally about 60 to 80% by weight.

As the thermoplastic resin and the plasticizer, the same thermoplastic resin and plasticizer as those used in the preparation of the paste can be used. The mixing ratio of the thermoplastic resin is 5 to 30% by weight. %, And the mixing ratio of the plasticizer is generally about 0 to 10% by weight.

As a general method for producing a green sheet, the above glass powder, ceramic powder, thermoplastic resin, plasticizer, etc. are prepared, and a main solvent such as toluene and an auxiliary solvent such as isopropyl alcohol are added thereto. The slurry is added to form a slurry, and the slurry is formed into a sheet on a film such as polyethylene terephthalate (PET) by a doctor blade method. After forming the sheet, the solvent and the solvent are removed by drying to obtain a green sheet.

The green sheet obtained as described above is thermocompression-bonded to a place where a glass layer is to be formed, and then fired to form a glass layer.
In the case of forming a partition, after forming a coating layer by thermocompression bonding, it is processed into a predetermined partition shape in the same manner as in the case of the paste described above.

In the above description, the partition wall forming method is described by taking the sand blast method using a paste or a green sheet as an example. However, the partition wall forming material for a plasma display panel of the present invention is not limited to these methods. It is a material that can be applied to other forming methods such as a printing lamination method, a lift-off method, a photosensitive paste method, a photosensitive green sheet method, and a press molding method.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.

Table 1 shows examples of the present invention (samples No. 1 to No. 1).
4) and a comparative example (sample No. 5).

[0033]

[Table 1]

Each sample was prepared as follows. First, glass materials such as various oxides and carbonates are prepared so as to have the compositions shown in the table, and after uniformly mixed, put into a platinum crucible and put in a platinum crucible.
Melting was performed at 250 ° C. for 2 hours to obtain a uniform glass body. Next, this was pulverized by an alumina ball mill, and the aperture was 53 μm.
And classified with a sieve.

The thermal expansion coefficient and softening point of the obtained glass powder were measured. As a result, no. Samples 1 to 4 had a coefficient of thermal expansion of 77.6 to 87.1 × 10 ⁻⁷ / ° C. and a softening point of 615 ° C. or less. On the other hand, No. Sample No. 5 had a high softening point of 653 ° C.

Next, a glass powder sample and various ceramic powders were mixed in the proportions shown in the table to obtain a partition wall forming material. The sinterability of the obtained sample was evaluated.

As a result, in the embodiment of the present invention, No. 1
Each of the samples Nos. To 4 exhibited good sinterability when fired at 600 ° C. On the other hand, in Comparative Example No. The sample of 5 is 60
When fired at 0 ° C., a dense sintered body could not be obtained.

The coefficient of thermal expansion of each sample was determined by powder press molding and firing, followed by polishing to a column having a diameter of 4 mm and a length of 40 mm, and measuring the temperature in accordance with JIS R3102. The values in the range were determined. The softening point of the glass is measured using a macro-type differential thermal analyzer,
The value of the fourth inflection point was taken as the softening point. The sinterability was evaluated as follows. First, each sample was treated with ethyl cellulose 5
% Terpineol solution and kneaded with a three-roll mill to form a paste. Next, this paste was applied on a window glass plate (coefficient of thermal expansion: 85 × 10 ⁻⁷ / ° C.) by a screen printing method to form a coating film having a thickness of 200 μm.
Subsequently, it was baked at 600 ° C. for 10 minutes in an electric furnace to obtain a glass film. Furthermore, after the oily ink was applied on the obtained glass film, it was wiped off with alcohol, and those that could be wiped off satisfactorily with the ink were indicated as “O”, and those that were difficult to wipe off with the ink soaked were indicated as “x” in the table. .

[0039]

As described above, the partition wall forming material for a plasma display panel of the present invention can form a dense partition wall at a firing temperature of 600 ° C. or less. Moreover, since glass powder containing no PbO or alkali metal oxide is used, there is no environmental problem or adverse effect on the performance of the plasma display panel.

Therefore, it is suitable as a partition wall forming material for a plasma display panel.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuo Hatano 2-7-1 Hararashi, Otsu-shi, Shiga F-term in Nippon Electric Glass Co., Ltd. 4G062 AA08 AA09 BB01 BB08 CC10 DA01 DA02 DA03 DA04 DB01 DC04 DC05 DD01 DE04 DE05 DE06 DF01 EA01 EB01 EC01 ED01 EE01 EF01 EG03 EG04 EG05 FA01 FA10 FB01 FC01 FD01 FE01 FF01 FG01 FH01 FJ01 FK01 FL01 GA01 GA10 GB01 GC01 GD01 GE01 HH01 HH03 HHH HH HH HH HH HH HH HH HH HH HH HH KK07 KK10 MM07 MM12 NN26 NN30 NN32 PP01 PP02 PP03 PP04 PP05 PP13 PP14 PP15 PP16 5C040 GF18 KA08 KA11 KB02 KB11

Claims (4)

[Claims] (1) 5 to 40% of BaO in mole%, ZnO
_{20~55%, B 2 O 3 15~50} %, SiO 2 0~
A partition wall forming material for a plasma display panel, comprising a glass powder having a composition of 25% as a constituent. 2. The glass powder according to claim 1, wherein the glass powder contains substantially no PbO and no alkali metal oxide.
For forming partition walls for plasma display panels. 3. The material for forming a partition wall for a plasma display panel according to claim 1, comprising 50 to 95% of glass powder and 5 to 50% of ceramic powder. 4. The composition according to claim 4, wherein the molar percentage of BaO is 5 to 40%, and that of ZnO is
_{20~55%, B 2 O 3 15~50} %, SiO 2 0~
A glass composition for forming a partition wall having a composition of 25%.