JP3556488B2 - Substrate for plasma display panel - Google Patents

Description

【００４７】
【表２】

【００４８】
【表３】

【００４９】
これらの表から明らかなように、セラミックフィラーを添加しない試料Ｎｏ．１、８、セラミックフィラーの添加量が７０重量部よりも少ない試料Ｎｏ．７、２５、２９ではビッカース硬度が低く、９０重量部よりも多い試料Ｎｏ．４、１２、１６、２０、２３、２７では、ビッカース硬度が低く、比誘電率および誘電損失が高くなり、ガラスの歪点が高くなる傾向にあることが判る。
【００５０】
一方、本発明の試料では、ビッカース硬度が４５０ｋｇ／ｍｍ^２ 以上で、１００ｋＨｚにおける比誘電率が８．０以下、かつ誘電損失が１．０％以下と優れた特性を有することが判る。
【００５１】
そして、Ｂ、Ｓｉ、Ｚｎと、アルカリ金属のうち少なくとも２種以上を含有するガラスを用い、このガラス１００重量部に対してセラミックフィラーを７５〜８５重量部含有する試料Ｎｏ．１０、１１、１４、１５、１８、１９では、ビッカース硬度が５００ｋｇ／ｍｍ^２ 以上で、１００ｋＨｚにおける比誘電率が７．０以下、かつ誘電損失が０．８％以下であることが判る。
【００５２】
そして、本発明者等は、セラミックフィラーの平均粒径とビッカース硬度の関係を調べるため、試料Ｎｏ．３のセラミックフィラーの平均粒径を変化させ、ビッカース硬度を測定した。その結果を図２に示す。この図２から、セラミックフィラーが１．０〜１．５μｍの場合にはビッカース硬度がピークを示し、０．５μｍに近づくに従い、または２．０μｍに近づくに従い、ビッカース硬度が低下する傾向にあることが判る。
【００５３】
【発明の効果】
本発明のＰＤＰ用基板では、隔壁を、ガラスと、ＺｒＯ_２ 、ＴｉＯ_２ 、Ａｌ_２ Ｏ_３ 、ＳｉＯ_２ 、ＭｇＯ、ＣａＯおよびＹ_２ Ｏ_３ のうち少なくとも１種類からなる所定量のセラミックフィラーとから構成したため、ビッカース硬度が４５０ｋｇ／ｍｍ^２ 以上で、１００ｋＨｚにおける比誘電率が８．０以下、かつ誘電損失が１．０％以下となり、隔壁のビッカース硬度が向上でき、その結果、高精細の隔壁を形成し、高画質化を図ることができるとともに、印加電圧パルスに対する応答性が良く、隔壁部でのエネルギー損失を低減でき、さらに、焼成温度が低く、絶縁基板の熱変形の影響が小さくなり隔壁の寸法精度が向上し、製造歩留まりを向上できる。
【図面の簡単な説明】
【図１】ＰＤＰの一部を示す断面図である。
【図２】セラミックフィラーの平均粒径とビッカース硬度との関係を示すグラフである。
【符号の説明】
１・・・板状絶縁基体
３・・・隔壁
７・・・アドレス電極
９・・・蛍光体
１１・・・正面板
１３・・・放電維持電極[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate for a plasma display panel (hereinafter, referred to as a PDP) in which a partition constituting a discharge display cell is formed on a plate-like insulating substrate.
[0002]
[Prior art]
Conventionally, CRTs, which have been widely used as image display devices, are disadvantageous in that they have a large volume and weight and require a high voltage. Therefore, with the recent penetration of multimedia, light-emitting diodes (LEDs) and liquid crystals are used as information interfaces. A flat image display device having features such as a display element (LCD), a large screen such as a PDP, a high image quality, a thin and light weight, and an installation location can be selected has been developed, and the range of use thereof has been expanding.
[0003]
As such a flat-panel image display device, a PDP utilizing plasma emission has attracted attention as a light-emitting element of a large-screen color image display device.
[0004]
In such a PDP, a pair of flat insulating substrates forming a back plate and a front plate, and opposing electrode groups are provided in a minute discharge display cell surrounded by a partition partitioning the space. It has a structure in which a dischargeable gas such as gas is hermetically sealed, and a voltage is selectively applied between the opposing electrodes to generate plasma by discharge, and discharge is caused by ultraviolet light emitted from the plasma. The phosphor formed on the inner wall of the display cell emits light and is used as a light emitting element of an image display device.
[0005]
Conventionally, a PDP disclosed in Japanese Patent Application Laid-Open No. 9-231910 is known as a PDP in which the reflectance of a back plate or a partition wall is increased.
[0006]
In the PDP disclosed in this publication, the partition walls are composed of lead-based glass and a ceramic filler having an average particle diameter of 0.2 to 1.5 μm, which is made of one of ZrO ₂ , TiO ₂ , and BN. The PDP contains 10 to 40% by weight of a ceramic filler, and in such a PDP, the reflectance of the back plate and the partition walls can be increased.
[0007]
[Problems to be solved by the invention]
However, the PDP disclosed in the above publication has a problem that it is difficult to form a high-definition partition wall because of its low hardness, and that the partition wall is easily chipped when the panel is sealed.
[0008]
Further, since the glass containing lead as a main component is as large as 60 to 90% by weight, there is a problem that the relative dielectric constant is large and the dielectric loss is large. As a result, the electric flux distribution during the address period cannot be concentrated in the discharge space, which causes a reduction in light emission luminance. In addition, the capacitance of the discharge display cell becomes large, and thus, when driving the PDP, However, there is a problem that the driving current between the discharge electrodes becomes large, the power consumption of the PDP is increased, and the power supply equipment is enlarged. Further, there is a problem that a delay occurs in a signal response.
[0009]
The present invention has been made in view of the above problems, and can improve the hardness, reduce the relative dielectric constant and the dielectric loss of the partition, improve the luminance, reduce the power consumption, and further respond to signals. It is an object of the present invention to provide a PDP substrate capable of improving performance.
[0010]
[Means for Solving the Problems]
The PDP substrate of the present invention is a plasma display panel substrate comprising a plate-shaped insulating base and a plurality of partitions formed on the plate-shaped insulating base, wherein the partition is made of glass (however, P ₂ O ₅ -based). (Excluding glass) and a ceramic filler comprising at least one of ZrO ₂ , TiO ₂ , Al ₂ O 3, SiO ₂ , MgO, CaO and Y ₂ O 3, wherein the ceramic filler is contained in 100 parts by weight of the glass. 70 to 90 parts by weight, and a Vickers hardness of 450 kg / mm ² or more . Here, it is desirable that the average particle size of the ceramic filler is 0.5 to 2 μm. Further, it is desirable that the glass contains B, Si, Zn as metal elements and at least two or more of alkali metals.
[0011]
Further, it is desirable that the relative permittivity of the partition wall of the plasma display panel substrate of the present invention at a measurement frequency of 100 kHz be 8.0 or less and the dielectric loss be 1.0% or less.
[0012]
[Action]
According to the PDP substrate of the present invention, the partition walls constituting the PDP discharge display cell are made of glass (however, excluding P ₂ O ₅ -based glass) , ZrO ₂ , TiO ₂ , Al ₂ O 3, SiO ₂ , and MgO. , CaO and Y ₂ O 3, containing 70 to 90 parts by weight of a ceramic filler based on 100 parts by weight of glass and having a Vickers hardness of 450 kg / mm ² or more. Thus, the partition walls of the PDP substrate can be made finer. This is because a large amount of ceramic filler exposed on the partition wall surface is baked in a uniform distribution state, so that it can maintain a dense surface state, and when an external force acts, the external force can be dispersed by the ceramic filler on the surface. It is.
[0013]
Further, since the amount of glass is small, the relative dielectric constant and the dielectric loss of the partition can be kept low even when a glass containing lead as disclosed in JP-A-9-231910 is used. Since the distribution can be concentrated in the discharge space, the emission luminance can be improved, and the capacitance of the discharge display cell can be reduced, the driving current between the discharge electrodes when driving the PDP can be reduced, and the power consumption of the PDP can be reduced. Can be reduced, and the response of the signal can be improved.
[0014]
Further, by setting the average particle size of the ceramic filler to 0.5 to 2 μm, the hardness of the partition walls can be further improved.
[0015]
Furthermore, since glass contains B, Si, Zn and at least two kinds of alkali metals as metal elements, lead-based glass as disclosed in JP-A-9-231910 is not used. Therefore, the relative dielectric constant and the dielectric loss can be further reduced, the emission luminance can be improved, the power consumption can be reduced, the firing temperature can be reduced, and the influence of thermal deformation on the plate-like insulating substrate is reduced, and the dimensional accuracy of the partition walls is reduced. And the production yield is improved.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, for example, as shown in FIG. 1, a PDP using the PDP substrate of the present invention includes a plate-shaped insulating substrate 1 (back plate) and a plurality of partition walls 3 formed integrally with the plate-shaped insulating substrate 1. The discharge display cell 5 is formed by the pair of partition walls 3. An address electrode 7 is formed on the bottom surface of the discharge display cell 5, and the address electrode 7 is covered with a protective film 8, and the protective film 8 is covered with a phosphor 9.
[0017]
On the other hand, a front plate 11 is joined to the upper surface of the partition 3, and a pair of discharge sustaining electrodes 13 are formed on the inner surface thereof. The discharge sustaining electrodes 13 are covered with a protective film 14.
[0018]
A dischargeable gas such as a rare gas is hermetically sealed in the discharge display cell 5, and a voltage is selectively applied between the opposing electrodes 7 and 13 to generate plasma by discharge, and the plasma is released from the plasma. The phosphor 9 formed on the inner wall of the discharge display cell 5 emits light by the ultraviolet light, and is used as a light emitting element of an image display device. The partition may have a black top on the top.
[0019]
The black top forming part of substrate for PDP barrier ribs or partition walls, the present invention is a glass _(except for P 2 _{O 5} based glass) _{and, ZrO 2, TiO 2, Al} 2 O3, SiO 2 , MgO, CaO, and Y ₂ O 3, comprising 70 to 90 parts by weight of the ceramic filler based on 100 parts by weight of glass, and having a Vickers hardness of 450 kg / mm ² or more. There is something. The P ₂ O ₅ glass is a glass containing 15% or more of P ₂ O ₅ .
[0020]
Here, at least one of ZrO ₂ , TiO ₂ , Al ₂ O ₃ , SiO ₂ , MgO, CaO and Y ₂ O ₃ was selected as the ceramic filler because of the high hardness of the ceramic filler itself and the firing. This is because they do not form a solid solution with glass. As the ceramic filler, TiO ₂ is desirable because it has a high hardness.
[0021]
Furthermore, the reason that the ceramic filler is contained in an amount of 70 to 90 parts by weight based on 100 parts by weight of glass is that the effect of increasing the hardness is small when the amount of the ceramic filler is less than 70 parts by weight based on 100 parts by weight of glass. Further, when lead-based glass is used, the relative dielectric constant and the dielectric loss increase because the amount of glass increases, and when it is more than 90 parts by weight, the hardness tends to decrease. In addition to this, the strain point of the glass increases, and low-temperature firing becomes difficult. The ceramic filler is desirably contained in an amount of 75 to 85 parts by weight in terms of partition wall hardness, relative dielectric constant, dielectric loss, and firing temperature.
[0022]
The average particle size of the ceramic filler is desirably 0.5 to 2 μm. This is because, when the average particle size is smaller than 0.5 μm, aggregation tends to occur when the slurry is mixed with glass to form a slurry. Is shed and becomes a defect. The average particle size of the ceramic filler is particularly preferably 0.8 to 1.6 μm.
[0023]
In the PDP substrate of the present invention, the glass can be fired at a low temperature of 550 ° C. or lower, and examples thereof include various glasses containing lead, alkali, phosphorus, and the like. From the viewpoint of having a dielectric property (small relative permittivity) for improving the light emission luminance of the PDP, it is more preferable to contain two or more kinds of alkali metals. This is because the alkali metal oxide acts as a flux when the glass is melted, lowering the melting point and preventing migration of the Ag electrode material of the PDP.
[0024]
In particular, the glass preferably contains at least two of B, Si, Zn, and alkali metals as metal elements. This is because the polarizability of the network component of the glass is reduced, so that the relative dielectric constant of the entire glass can be reduced, thereby improving the emission luminance and reducing the power consumption.
[0025]
Examples of the alkali metal include Li, Na, K, Rb, and Cs. Of these, from the viewpoint of preventing migration of a metal component ionized from the Ag electrode, it is easy to form a cluster of different alkali oxides. A greatly different combination is preferable. For example, it is desirable to use a combination of Li and Cs and a combination of Na and Rb.
[0026]
In addition, in terms of having dielectric properties particularly suitable for improving light emission luminance, and having mechanical strength and chemical durability in a manufacturing process, such glasses include zinc borosilicate-based glass and oxides of alkali metals. Is more desirable.
[0027]
In particular, as the glass for the reasons detailed below, respectively, and 25 to 60 wt% _B 2 _{O 3,} and 20 to 45 wt% of ZnO, and SiO ₂ of 10 to 40 wt%, 5 wt % and _Al 2 _{O 3,} and consists of 2-8 wt% of ZrO ₂ Metropolitan desirably contains 6-14% by weight in terms of oxide of two or more of the alkali metals.
[0028]
That is, in the composition of the zinc borosilicate glass, B ₂ O ₃ acts as a flux at the time of melting the glass and has an effect of producing a strong glass. The coefficient of expansion can be made close to the coefficient of thermal expansion of the plate-shaped insulating substrate.
[0029]
Further, SiO ₂ is a main component of the high-melting glass for increasing the surface hardness and has an effect of lowering the relative dielectric constant. By containing 10 to 40% by weight, the strain point and the relative dielectric constant are reduced. Lowering the surface hardness.
[0030]
On the other hand, ZnO has an effect of lowering the strain point, and its chemical durability can be increased by containing 20 to 45% by weight.
[0031]
Further, Al ₂ O ₃ is contained to prevent phase separation of glass, improve chemical durability, increase the strength of partition walls, and match the coefficient of thermal expansion with the plate-like insulating substrate. By containing the content of about 5% by weight, the strain point can be reduced and the strength of the partition wall can be improved.
[0032]
ZrO ₂ contributes to whitening of the partition walls, and is desirably contained in an amount of 2 to 8% by weight in view of the strain point.
[0033]
Furthermore, the content of 6 to 14% by weight in terms of oxide of two or more of the alkali metals is that when the content is less than 6% by weight, the relative permittivity is high, the strain point is high, and when the content is more than 14% by weight, This is because migration of the Ag electrode material easily occurs.
[0034]
The PDP substrate of the present invention may further contain a third component as appropriate, in addition to the low-temperature sinterable glass and the ceramic filler, to obtain electrical characteristics such as relative permittivity, dielectric loss, and insulation resistance. It is also possible to adjust the expansion coefficient.
[0035]
In addition, by using the above ceramic filler, a partition constituting a discharge display cell of a PDP can be formed by laminating on a plate-shaped insulating substrate, or a partition formed body can be sagged or bent or warped due to melting of a low-melting substance. This also has the effect of suppressing deformation of the molded article and improving the strength of the molded article.
[0036]
The partition wall of the PDP substrate of the present invention has a Vickers hardness of 450 kg / mm ² or more, a relative dielectric constant at 100 kHz of 8.0 or less, and a dielectric loss of 1.0% or less.
[0037]
The reason for setting the Vickers hardness to 450 kg / mm ² or more is that if it is less than 450 kg / mm ² , it becomes difficult to form high-definition partition walls, and high-definition image quality cannot be obtained. When the relative dielectric constant at 100 kHz exceeds 8.0, the electric flux distribution cannot be sufficiently concentrated in the discharge space, and the effect of improving light emission luminance and reducing power consumption is set to 8.0 or less. Is smaller.
[0038]
Further, the reason why the dielectric loss of the partition wall at the measurement frequency of 100 kHz is set to 1.0% or less is that if the dielectric loss exceeds 1.0%, the energy loss in the partition wall and the response delay to the applied voltage pulse are large and the power consumption increases. This is because it may cause them to do so.
[0039]
In particular, in the PDP substrate of the present invention, it is more preferable that the Vickers hardness is 500 kg / mm ² or more, the relative dielectric constant at 100 kHz is 7.0 or less, and the dielectric loss is 0.5% or less.
[0040]
If the strain point of the glass is less than 400 ° C., deformation such as bending or warpage of the partition walls tends to occur during firing, and if it exceeds 500 ° C., it becomes difficult to fire for a short time. Therefore, in the present invention, the strain point of the glass is desirably in the range of 400 to 500 ° C., and the sintering may be performed by densifying the composition for partition walls and intimately adhering to the plate-like insulating substrate. It is sufficient that the temperature be equal to or higher than the strain point and equal to or lower than the strain point of the plate-shaped insulating substrate made of glass. Specifically, the temperature range is preferably 530 to 550 ° C.
[0041]
【Example】
First, the glass raw material powder shown in Table 1 and the ceramic filler of Table 1 having various average particle diameters were weighed at the ratio shown in Table 2 with respect to 100 parts by weight of the glass raw material powder, and were weighed with isopropyl alcohol (IPA). ) Was used as a solvent and wet-mixed for 18 hours in a ball mill using zirconia balls.
[0042]
Thereafter, a binder was added to the pulverized mixture, and the mixture was stirred. The obtained granules were passed through a 50-mesh net and formed into a disc having a diameter of 20 mm and a thickness of 4 mm at a pressure of 1000 kg / cm ^2. Was fired at each firing temperature shown in Table 3 for 20 minutes.
[0043]
Thereafter, the disc-shaped fired body was polished to produce a disc having a diameter of 17 mm and a thickness of 2 mm, and In-Ga electrodes were applied to both end faces to obtain a sample for evaluation.
[0044]
The relative permittivity and the dielectric loss of the evaluation sample thus obtained were measured using an LCR meter under the conditions of an atmosphere temperature of 25 ° C. and a measurement frequency of 100 kHz (AC 100 V).
[0045]
On the other hand, a binder was added to the pulverized mixture, and the mixture was stirred. The slurry obtained through a 50-mesh net was applied on a glass substrate and dried, and then baked at a temperature shown in Table 3 for 20 minutes. Was polished. The surface hardness of the evaluation sample thus obtained was measured with a micro Vickers hardness meter having a standard load of 98.07 N. These results are shown in Table 3.
[0046]
[Table 1]

[0047]
[Table 2]

[0048]
[Table 3]

[0049]
As is clear from these tables, Sample No. with no ceramic filler added. Sample Nos. 1 and 8 in which the amount of the ceramic filler added was less than 70 parts by weight. Samples Nos. 7, 25 and 29 have low Vickers hardness, and are larger than 90 parts by weight. 4, 12, 16, 20, 23, and 27 show that the Vickers hardness tends to be low, the relative dielectric constant and the dielectric loss tend to be high, and the strain point of the glass tends to be high.
[0050]
On the other hand, it is understood that the sample of the present invention has excellent properties such as a Vickers hardness of 450 kg / mm ² or more, a relative dielectric constant at 100 kHz of 8.0 or less, and a dielectric loss of 1.0% or less.
[0051]
Then, a glass containing B, Si, Zn, and at least two or more of alkali metals was used. 10, 11, 14, 15, 18, and 19 indicate that the Vickers hardness is 500 kg / mm ² or more, the relative dielectric constant at 100 kHz is 7.0 or less, and the dielectric loss is 0.8% or less.
[0052]
Then, the present inventors investigated the relationship between the average particle size of the ceramic filler and the Vickers hardness. The Vickers hardness was measured while changing the average particle size of the ceramic filler of No. 3. The result is shown in FIG. From FIG. 2, when the ceramic filler is 1.0 to 1.5 μm, the Vickers hardness shows a peak, and the Vickers hardness tends to decrease as the thickness approaches 0.5 μm or 2.0 μm. I understand.
[0053]
【The invention's effect】
In the PDP substrate of the present invention, the partition walls are made of glass and a predetermined amount of ceramic filler composed of at least one of ZrO ₂ , TiO ₂ , Al ₂ O ₃ , SiO ₂ , MgO, CaO and Y ₂ O _3. With this configuration, the Vickers hardness is 450 kg / mm ² or more, the relative dielectric constant at 100 kHz is 8.0 or less, and the dielectric loss is 1.0% or less, and the Vickers hardness of the partition walls can be improved. To improve the image quality, have good response to the applied voltage pulse, reduce the energy loss at the partition wall, further reduce the firing temperature, and reduce the influence of thermal deformation of the insulating substrate. The dimensional accuracy of the partition is improved, and the production yield can be improved.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a part of a PDP.
FIG. 2 is a graph showing the relationship between the average particle size of a ceramic filler and Vickers hardness.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Plate-shaped insulating base 3 ... Partition 7 ... Address electrode 9 ... Phosphor 11 ... Front plate 13 ... Discharge sustaining electrode

Claims (4)

In a plasma display panel substrate including a plate-shaped insulating substrate and a plurality of partitions formed on the plate-shaped insulating substrate, the partition is made of glass (however, excluding P ₂ O ₅ -based glass) , ZrO ₂ , TiO ₂ , Al ₂ O ₃ , SiO ₂ , MgO, CaO and ceramic filler comprising at least one of Y ₂ O ₃ , wherein the ceramic filler is 70 to 90 parts by weight based on 100 parts by weight of the glass. A substrate for a plasma display panel , comprising: a Vickers hardness of 450 kg / mm ² or more . 2. The plasma display panel substrate according to claim 1, wherein the ceramic filler has an average particle size of 0.5 to 2 [mu] m. 3. The substrate for a plasma display panel according to claim 1, wherein the glass contains B, Si, Zn as a metal element and at least two or more of alkali metals. The plasma display panel substrate according to any one of claims 1 to 3, wherein a relative dielectric constant of the partition wall at a measurement frequency of 100 kHz is 8.0 or less and a dielectric loss is 1.0% or less.

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