KR20070086978A - Glass for coating electrode, front substrate of plasma display panel and back substrate of plasma display panel - Google Patents

Abstract

A glass for coating an electrode which contains Cu in an amount of 0. 05 to 2 mole % in terms of CuO and Co in an amount of 0.05 to 2 mole % in terms of CoO; and a glass for coating an electrode which consists essentially of, in mole % and in terms of the oxides described bellow, 20 to 60 % of B2O3, 5 to 50 % of SiO2, 10 to 40 % of PbO + ZnO, 0 to 15 % of Al2O3, 0 to 20 % of SrO + BaO, 0 to 10 % of TiO2, 0 to 9 % of Bi2 O3, 0 to 16 % of Li2O + Na2O + K 2O, 0.05 to 2 % of CuO, 0.05 to 2 % of CoO, 0 to 2 % of CeO 2, and 0 to 2 % of MnO2.

Description

GLASS FOR COATING ELECTRODE, FRONT SUBSTRATE OF PLASMA DISPLAY PANEL AND BACK SUBSTRATE OF PLASMA DISPLAY PANEL}

The present invention relates to a front substrate and a back substrate of a plasma display panel (hereinafter referred to as a PDP), and an electrode coating glass suitable for electrode coating of these substrates.

In recent years, a thin flat panel type color display device attracts attention. In such a display device, an electrode is formed in each pixel in order to control the display state in the pixel which forms an image. As such an electrode, in order to prevent the image quality deterioration, transparent electrodes, such as a thin film of ITO or tin oxide formed on the glass substrate, are used.

The transparent electrode formed on the surface of the glass substrate used as a display surface of the said display apparatus is processed into a thin line in order to implement | achieve a fine image. In order to control each pixel independently, it is necessary to ensure insulation between such finely processed transparent electrodes. By the way, when moisture exists in the surface of a glass substrate, or when an alkali component exists in a glass substrate, some electric current may flow through the surface of this glass substrate. In order to prevent such a current, it is effective to form an insulating layer between the transparent electrodes. Moreover, it is preferable that this insulating layer is transparent so that the fall of the quality of an image by the insulating layer formed between transparent electrodes can be prevented.

Although various things are known as an insulating material which forms such an insulating layer, the glass material which is a transparent and highly reliable insulating material is especially used widely.

In PDPs, which are expected as large-sized flat-panel display devices in recent years, a front substrate used as a display surface and a back substrate on which partition walls are formed are attached, and cells are partitioned by partition walls. And an image is formed by generating a plasma discharge in the cell.

The transparent electrode is formed in the surface of the glass substrate of a front substrate, and in order to protect this transparent electrode from a plasma, it is essential to coat the said transparent electrode with glass excellent in plasma durability.

Moreover, an address electrode is formed in the surface of the glass substrate of a back substrate, and this address electrode is also coat | covered with glass.

The glass used for such electrode coating is normally used as glass powder. For example, the said glass powder which adds a filler etc. to the said glass powder as needed, mixes it with resin, a solvent, etc., and makes it into a glass paste, and apply | coats this to the glass substrate in which electrodes, such as a transparent electrode, are formed and baked, The resin is coated with a glass by a method such as a resin obtained by mixing a filler or the like, if necessary, on a green sheet, which is then laminated on a glass substrate on which the electrode is formed, and then fired.

The glass used for the transparent electrode coating of the PDP front substrate has a softening point Ts of 450 to 650 ° C and an average linear expansion coefficient at 50 to 350 ° C, in addition to the electrical insulation as described above. ) Is ^60x10 <^-7> -90 * 10 <^-7> / degreeC, high transparency of the electrode coating glass layer obtained by baking, etc. are calculated | required, and various glass is proposed conventionally.

In the PDP front substrate, a color filter layer is usually formed on the electrode coating glass layer for the purpose of contrast enhancement, etc. In recent years, a colored glass is used as the electrode coating glass layer so that the formation of the color filter layer is unnecessary, and thus the contrast of the screen is obtained. Is proposed (see Table 1 of Japanese Patent Laid-Open No. 2000-226229).

As mentioned above, using colored glass as an electrode coating glass layer so that formation of a color filter layer is unnecessary is proposed conventionally, However, it is not yet widely used.

Although the cause is not necessarily clear, the glass for electrode coating disclosed by Unexamined-Japanese-Patent No. 2000-226229 contains only CoO and NiO as a coloring component, and it may be the said cause.

An object of the present invention is to provide an electrode coating glass which enables the elimination of this possibility, and a PDP front substrate and a PDP back substrate using such a glass for electrode coating.

Means to solve the problem

This invention provides Cu and Co, the electrode coating glass (1st glass of this invention) whose CuO conversion content of Cu is 0.05-2 mol%, and CoO conversion content of Co is 0.05-2 mol%. .

In addition, in the mole percentage display on the basis of the following oxides, B ₂ O ₃ 20 to 60%, SiO ₂ 5 to 50%, PbO + ZnO 10 to 40%, Al ₂ O ₃ 0 to 15%, SrO + BaO 0 to 20 %, TiO ₂ 0-10%, Bi ₂ O ₃ 0-9%, Li ₂ O + Na ₂ O + K ₂ O 0-16%, CuO 0.05-2%, CoO 0.05-2%, CeO ₂ 0- _2%, MnO 2 0 ~ glass electrode coating that is essentially from 2% to provide (second glass of the present invention).

Moreover, the PDP front substrate in which the glass substrate in which the transparent electrode is formed is coat | covered with the glass layer is provided, The glass of a glass layer is a 1st or 2nd glass of this invention.

Moreover, the glass substrate in which the electrode is formed is coat | covered with the glass layer, and the partition wall is formed on this glass layer, The glass of a glass layer is a PDP rear substrate which is the 1st or 2nd glass of this invention. To provide.

Effects of the Invention

As a PDP front substrate in which a color filter layer is not formed, it is obtained that the electrode coating glass layer does not contain only CoO and NiO as a coloring component.

Moreover, it becomes possible to suppress the yellowing phenomenon of the peripheral part of the silver electrode of the electrode coating glass layer as a PDP front substrate in which silver electrode is used as a bus electrode etc.

To practice the invention  Best form for

Hereinafter, the case where the glass for electrode coating of this invention (henceforth simply called glass of this invention) is used as an electrode coating glass layer of a PDP front substrate is demonstrated. In addition, this invention is not limited to this case.

The glass of this invention is normally used as glass powder. For example, the glass powder of this invention becomes a glass paste using the organic vehicle for giving printability, etc., and apply | coats and bakes the said glass paste on the electrode formed on the glass substrate, and coat | covers an electrode. The organic vehicle referred to herein is obtained by dissolving a binder such as ethyl cellulose in an organic solvent such as α-terpineol. Or the slurry obtained by mixing resin, further filler, etc. with the glass powder of this invention is shape | molded in the green sheet, this is laminated on the glass substrate in which the electrode is formed, and it bakes, and coat | covers an electrode.

It is preferable that Ts of the glass of this invention is 450-650 degreeC. When Ts is more than 650 degreeC, there exists a possibility that the glass substrate (glass transition point: 550-620 degreeC) normally used may deform | transform at the time of baking.

In the case of using a glass substrate having a glass transition point of 610 to 630 ° C, the Ts is preferably 630 ° C or less, and more preferably 550 to 600 ° C.

Moreover, when using for the electrode coating glass layer of a single | mono layer structure, the said Ts becomes like this. Preferably it is 520 degreeC or more, More preferably, it is 550 degreeC or more, When using a glass substrate whose glass transition point is 610-630 degreeC, It is especially preferable that Ts is 580 degreeC or more.

As said glass substrate, the thing of (alpha) 80 * 10 <^-7> -90 * 10 <^-7> / ^degreeC is used normally. Therefore, in order to match such a glass substrate and an expansion characteristic, and to prevent the curvature and the fall of strength of a glass substrate, (alpha) of the glass of this invention becomes like this. Preferably it is 60 * 10 <^-7> -90 * 10 <^-7> / degreeC, More preferably Preferably it is 70 * 10 <^-7> -85 * 10 <^-7> / ^degreeC .

As for the glass of this invention, it is preferable that Ts is 450-650 degreeC and (alpha) is 60 * 10 <^-7> -90 * 10 <^-7> / ^degreeC .

The dielectric constant at 1 MHz of the glass of this invention is 8-13 typically.

When the glass of this invention was formed as a glass layer with a thickness of 30-35 micrometers on the glass substrate used as a glass substrate of a PDP, when the glass layer has a wavelength of 450 nm, 550 nm, and 630 nm with respect to the glass substrate in which the glass layer was formed, The transmittance (unit:%) of each light is preferably T ₄₅₀ , T ₅₅₀ , T ₆₃₀ , respectively, T ₄₅₀ > T ₅₅₀ > T ₆₃₀ or -2% <(T ₄₅₀ -T ₅₅₀ ) <0%.

In _{addition, T 450, T 550, T} 630 is preferably not less than 65% of all.

Further, as the glass substrate PD200 of Asahi Glass manufacturing the glass substrate _{(T 450 = 89%, T} 550 = 90%, T 630 = 88%) having a thickness of 2.8㎜ it is illustrated.

When the glass of this invention is used for the glass layer which coat | covers a silver electrode, it is preferable that the yellowing phenomenon of the peripheral part of a silver electrode hardly arises or does not occur. The yellowing phenomenon is a phenomenon in which the glass is colored brown or yellow and the image quality of the PDP is deteriorated, which is caused by the diffusion of silver of the electrode into the glass layer covering the silver electrode.

Next, the component of the glass of this invention is demonstrated. In addition, for example, Cu exists in the form of CuO in glass, and handles CuO as a component, Cu0 conversion content is abbreviated as CuO, and content of each component is shown by molar percentage display except for Ni.

CuO is a component for realizing the preferable relationship shown above with respect to T ₄₅₀ , T _550, and T ₆₃₀ , or as a component which makes the yellowing phenomenon difficult or does not occur. When CuO is less than 0.05%, it becomes difficult to realize the said preferable relationship, or the said yellowing phenomenon becomes easy to occur, Preferably it is 0.1% or more. When CuO exceeds 2%, the transmittance of glass decreases, and in particular, T ₅₅₀ decreases, preferably 0.9% or less, and when it contains 24% or more of PbO, it is typically 0.4% or less.

CoO is essential as a component for realizing the said preferable relationship. If CoO is less than 0.05%, it is difficult to realize the above preferable relationship, preferably 0.1% or more, and more than 2%, the transmittance of glass decreases, and in particular, T ₆₃₀ decreases, preferably less than 1%.

CeO ₂ is not essential, but in the case of adjusting the color tone of the glass in the yellow direction, it may contain up to 2%. When CeO ₂ is more than 2%, the transmittance of glass decreases, and in particular, T ₄₅₀ decreases, preferably 1% or less. If containing a CeO ₂ content thereof is preferably not less than 0.1%.

MnO ₂ is not required, but if, for example, to adjust the color tone of the glass in the red direction, may contain up to 2%. When MnO ₂ exceeds 2%, the transmittance of glass decreases, and in particular, T ₅₅₀ decreases, preferably 1% or less. When it contains Mn0 ₂ , the content is preferably 0.1% or more, and typically 0.2% or more.

The glass of the present invention typically contains no NiO or, if it contains NiO, its content is less than 0.005% in terms of mass percentage.

The first glass of the present invention is typically a B ₂ O ₃ —SiO ₂ -based glass.

Next, the component of the 2nd glass of this invention is demonstrated. Further, for the CuO, CoO, CeO ₂ and Mn0 ₂ will not be specifically described herein avoid redundancy as described above.

B ₂ O ₃ is a glass network structure-forming components, is required. B ₂ O ₃ is less than 20% the glass is unstable, preferably by not less than 26%, and 60% greater than Ts is too high, preferably 55% or less, and typically not more than 50%.

SiO ₂ is essential as a glass network structure forming component. The SiO ₂ is less than 5%, the glass is unstable fixed, typically with 7% and at least 50% greater than the Ts is too high, preferably not more than 35% and typically is 26% or less.

PbO and ZnO are components having the effect of lowering Ts and must contain at least one. When the sum total of content of PbO and ZnO is less than 10%, the said effect is small, and is typically 18% or more, and when it exceeds 40%, there exists a possibility that alpha may become too large, or glass becomes easy to crystallize, Preferably it is 35% Below, it is typically 30% or less.

When it contains PbO, the content becomes like this. Preferably it is 10 to 35%, typically 21 to 29%. If PbO is more than 35%, α may be too large.

When it contains ZnO, its content becomes like this. Preferably it is 10 to 30%, typically 15 to 25%. When ZnO is more than 30%, glass will become easy to crystallize.

Al ₂ O ₃ is not essential, but may be contained up to 15% in order to stabilize the glass more. Al ₂ O ₃ is apt to be in a 15% excess of the glass is crystallized, is preferably 10% or less, typically less than 8%. When containing Al ₂ O ₃ content thereof is preferably at least 1%, typically not less than 3%.

Although both SrO and BaO are not essential, you may contain in the range up to 20% in the case of making alpha large. If the total is more than 20%, α may be too large, preferably 16% or less. When it contains at least one of SrO and BaO, it is preferable that the sum total of content of SrO and BaO is 5% or more, and is typically 8% or more. Moreover, in that case, it is preferable to contain BaO.

When it contains BaO, the content is typically 8 to 16%.

When it contains SrO, the content is typically 10% or less.

TiO ₂ is not essential, but may be contained up to 10% in order to increase the relative dielectric constant. If TiO ₂ is more than 10%, the glass tends to crystallize, and is typically 7% or less. When it contains TiO ₂ , the content is preferably 1% or more, typically 3% or more.

Bi ₂ O ₃ is not essential, it may be contained if, for example, to increase the dielectric constant to decrease the character Ts and has up to 9%. If Bi ₂ O ₃ is more than 9%, α may be too large, and typically 4% or less. If containing Bi ₂ O ₃ content thereof is preferably at least 1%.

If, for example, both Li ₂ O, Na ₂ O and K ₂ O are not essential, lowering the Ts and chairs may contain in the range of up to 16% in total. If the total is more than 16%, α may be too large, preferably 9% or less. When it contains any one or more of Li ₂ O, Na ₂ O and K ₂ O, the sum of the contents of these three components is preferably 2% or more, and typically 3% or more. In that case, typically, Li ₂ O is contained.

If containing a Li ₂ O content thereof is typically from 2 to 9%.

The sum of their contents when containing Na ₂ O and at least any one of a K ₂ O is typically not more than 10%.

Although the 2nd glass of this invention consists essentially of the said component, you may contain other components in the range which does not impair the objective of this invention. In that case, it is preferable that the sum total of content of such a component is 10% or less.

May be mentioned as a preferable embodiment of the second glass of the present invention, B ₂ O ₃ is a 20 ~ 55%, PbO is 10 ~ 35%, ZnO 0 to 10%, SrO 0 to 15%.

In addition, as another preferred embodiment, B ₂ O ₃ is 20 ~ 50%, SiO ₂ is 5 ~ 35%, ZnO is _{10 ~ 30%, Al 2 O} 3 is 0 ~ 10%, SrO is 0 ~ 10%, BaO It is and _{0 ~ 16%, Na 2 O} + K 2 O is 0 to 10%, those containing no PbO.

Next, the manufacturing method of the PDP front substrate of this invention is demonstrated.

The layer containing the glass powder of this invention is formed so that the transparent electrode and bus electrode formed on the glass substrate may be coat | covered.

The said transparent electrode is a strip | belt-shaped of 0.5 mm in width, for example, and is formed so that each strip | belt-shaped electrode may be mutually parallel. The distance between each strip | belt-shaped electrode center line is 0.83-1.0 mm, for example, In this case, the ratio which a transparent electrode occupies on a glass substrate surface is 50 to 60%.

In addition, the bus electrode is formed so as to correspond to the transparent electrode, and is generally made of silver or Cr-Cu-Cr.

In the case of forming the layer containing the glass powder of the present invention, when using the printing method, a filler or the like is added to the glass powder of the present invention if necessary, and then mixed with a resin, a solvent or the like to form a glass paste, which forms a transparent electrode. In the case of applying to a glass substrate, and using the green sheet method, a slurry obtained by mixing the resin with a glass, a filler, and the like, if necessary, is molded into a green sheet and laminated on a glass substrate having electrodes formed thereon. Do it.

The glass substrate in which the layer containing the glass powder of this invention was formed is heated, this layer is baked and it becomes an electrode coating glass layer, and then the layer of magnesium oxide is formed as a protective film on this electrode coating glass layer, and PDP It becomes a front substrate.

In addition, the structure etc. which were shown in the above description are examples, and the PDP front substrate of this invention is not limited to this.

The PDP back substrate of this invention is manufactured according to the manufacturing method of the PDP front substrate of this invention. That is, the layer containing the glass powder of this invention which coat | covers the address electrode on a glass substrate is formed similarly to the manufacturing method of the PDP front substrate of this invention.

The address electrode generally consists of silver or Cr-Al.

When it is desired to impart light reflectivity, light shielding properties, or the like to the electrode-coated glass layer of the PDP back substrate of the present invention, it is preferable to include a filler (including a pigment) in the layer containing the glass powder of the present invention. have. Moreover, as a pigment, what contains one or more elements chosen from the group which consists of Al, Si, Ti, Cr, Mn, Co, and Cu is common.

In the said preferable case, when the layer containing the glass powder of this invention contains a pigment as a filler, it is preferable to make a glass powder of this invention 100 mass parts, and to contain a pigment in the ratio of 0.5-40 mass parts.

The raw materials were prepared and mixed so that the column from B ₂ O ₃ to MnO ₂ in the table could be represented by mole percentage display, melted for 1 hour using a platinum crucible in an electric furnace at 1100 to 1350 ° C, and molded into thin glass. Then, it grind | pulverized with the ball mill and obtained glass powder. Examples 1-17 are Examples, and 18 is a comparative example.

About these glass powders, the softening point Ts (unit: degreeC), the average linear expansion coefficient (alpha) (unit: ^10-7 / degreeC) in 50-350 degreeC, and the dielectric constant (epsilon) in 1 MHz are measured as described below. It was. The results are shown in the table.

Ts: It measured using the differential thermal analyzer in the range up to 800 degreeC.

(alpha): The baked body obtained by baking a powder for 10 minutes at the temperature 30 degreeC higher than Ts after pressure shaping | molding is processed into the column shape of diameter 5mm and length 2cm, and the average linear expansion coefficient in 50-350 degreeC with a thermal expansion system. Was measured.

(epsilon) Glass powder was remelted, shape | molded after plate shape, it processed, and it was set as the measurement sample of 50 mm x 50 mm, and thickness 3mm. Aluminum electrodes were produced by vapor deposition on both surfaces of the measurement sample, and the dielectric constant at the frequency of 1 MHz was measured using an LCR meter.

In addition, 100 g of the glass powder was kneaded with 25 g of an organic vehicle to prepare a glass paste. In addition, the organic vehicle was produced by dissolving 12% of ethyl cellulose in? -Terpineol in a mass percentage display.

Next, a glass substrate (PD200, manufactured by Asahi Glass Co., Ltd.) having a size of 50 mm × 75 mm and a thickness of 2.8 mm was prepared, and a silver paste for screen printing was printed on a portion of the surface 48 mm × 73 mm of the glass substrate and baked, Formed. Further, the glass substrate is a mass percentage shown _{compositions, SiO 2 58%, Al 2} O 3 7%, Na 2 O 4%, K 2 O 6.5%, MgO 2%, CaO 5% SrO 7%, BaO 7.5 %, ZrO ₂ 3%, and a glass transition point of 626 ° C. and α having 83 × 10 ⁻⁷ / ° C. and a phosphorus glass.

Thus, the glass substrate in which the silver layer was formed, and the glass substrate in which the silver layer was not formed were prepared, and the said glass paste was uniformly screen-printed in each 50 mm x 50 mm part, and it dried at 120 degreeC for 10 minutes. These glass substrates were heated at a temperature increase rate of 10 deg. C / min until the temperature reached Ts, and again, the temperature was maintained at Ts for 30 minutes and fired. Thus, the thickness of the glass layer formed on the glass substrate was 30-35 micrometers.

The light transmittance T ₄₅₀ (unit:%), T ₅₅₀ (unit:%), T ₆₃₀ (light transmittance of wavelength 450nm, 550nm, 630nm) with respect to the sample in which the said glass layer was formed on the glass substrate in which the silver layer is not formed. Unit:%) was measured as described below.

T ₄₅₀ , T ₅₅₀ , T ₆₃₀ : The transmittance of light having a wavelength of 450 nm, 550 nm, and ₆₃₀ nm was measured using an integrated spherical magnetic spectrophotometer U-3500 manufactured by Hitachi, Ltd. (state without sample was 100%). ).

Moreover, the presence or absence of the yellowing phenomenon was investigated about the sample in which the said glass layer was formed on the glass substrate in which the silver layer was formed. As a result, the yellowing phenomenon that the color of any of the glass layers in Examples 1 to 18 was also colorless, blue or cyan, and the color of the glass layer became brown or yellow was not observed.

The glass of the present invention can be used for electrode coating of the front or back substrate of a PDP.

In addition, the PDP front substrate and PDP back substrate of the present invention can be used for the production of PDP.

In addition, all the content of the JP Patent application 2005-7898, a claim, drawing, and the abstract for which it applied on January 14, 2005 is referred here, and it takes in as an indication of the specification of this invention.

Claims (10)

Glass for electrode coating containing Cu and Co, whose CuO conversion content of Cu is 0.05-2 mol%, and CoO conversion content of Co is 0.05-2 mol%. The method of claim 1, Containing Ce, and the CeO ₂ content is 2 mol% or less in terms of the electrode for coating glass. The method according to claim 1 or 2, Containing Mn, and the MnO ₂ in terms of the content is 2 mol% or lower electrode for coating glass. The method according to claim 1, 2 or 3, B ₂ O ₃ -SiO ₂ based glass electrode coating glass. In terms of mole percentage based on the following oxides, B ₂ O ₃ 20 to 60%, SiO ₂ 5 to 50%, PbO + ZnO 10 to 40%, Al ₂ O ₃ 0 to 15%, SrO + BaO 0 to 20%, TiO ₂ 0-10%, Bi ₂ O ₃ 0-9%, Li ₂ O + Na ₂ O + K ₂ O 0-16%, CuO 0.05-2%, CoO 0.05-2%, CeO ₂ 0-2% , MnO ₂ 0 ~ glass electrode coating that is essentially from the 2%. The method of claim 5, B ₂ O ₃ is 20 ~ 55%, PbO is 10 ~ 35%, ZnO 0 to 10%, the electrode for coating glass SrO 0 to 15%. The method of claim 5, B ₂ O ₃ is 20 to 50%, SiO ₂ is 5 to 35%, ZnO is 10 to 30%, Al ₂ O ₃ is 0 to 10%, SrO is 0 to 10%, BaO is 0 to 16%, Na O + K ₂ O is 0, ₂ ~ 10%, a glass electrode coating containing no PbO. The method according to any one of claims 1 to 7, The electrode coating glass which does not contain Ni or contains Ni and whose NiO conversion content is less than 0.005% by the mass percentage display. A plasma display panel front substrate wherein a glass substrate on which a transparent electrode is formed is covered with a glass layer, wherein the glass of the glass layer is the electrode coating glass according to any one of claims 1 to 8. Board. The glass substrate in which the electrode is formed is coat | covered with the glass layer, and the partition is formed on the glass layer, and the glass of a glass layer is a board | substrate of any one of Claims 1-8. The plasma display panel back substrate which is the glass for electrode coating described.