JP4296490B2 - Display materials - Google Patents

Description

The present invention (hereafter, PDP) The plasma display, a field emission display, a liquid crystal display, used in sheet display or the like, such as those related to the display for member of the partition wall and the back plate.

For example, in a gas discharge image display device such as a PDP, a glass partition is formed as a partition for forming one discharge space and preventing color interference between adjacent cells. Further, soda lime glass or high strain point glass having a thermal expansion coefficient (20 to 500 ° C.) of about 4 to 10 × 10 ⁻⁶ / ° C. is mainly used for the front and back plates of the PDP.
The partition wall, which is one of the PDP members, is mainly made of glass containing lead, and is manufactured by applying a paste on the back plate and then forming holes mainly by the sandblast method. However, the manufacturing method of such a partition wall is complicated, and the partition wall is prone to chipping and the yield is low, so that the productivity is low and the cost is high. Since the removed glass powder contains a lot of harmful lead, it is not environmentally preferable.
In addition, the performance of the PDP largely depends on the structure of the partition wall. In particular, for high definition and high brightness, the width of the partition wall separating the cells is reduced to increase the aperture ratio, and a high partition wall is provided. It is necessary to increase the discharge space by forming the discharge space, but since the glass barrier ribs are fragile, it is difficult to reduce the width of the barrier ribs separating cells and to form a high barrier rib. is there.

In order to solve the above-described problem, a metal partition wall on which a dielectric material containing glass is formed by an electrodeposition method has been proposed in, for example, Japanese Patent Laid-Open No. 3-205738 (see Patent Document 1). Japanese Patent Laid-Open No. 2000-64027 (see Patent Document 2) proposes a metal partition wall in which Al ₂ O ₃ is formed on the surface by vapor deposition.
Thus, when using a metal material as a partition instead of a glass material, a metal adjusted by rolling or the like to a desired thickness is used as a substrate, a predetermined through hole is formed in the metal substrate, and a front plate and a back plate are formed. By sticking together so as to be sandwiched between, discharge spaces corresponding to display pixels can be formed. Since the etching process can be applied to the formation of the through hole, the process is easy and no harmful lead is discharged. In addition, the height of the partition wall can be made higher than the partition wall made of glass depending on the thickness of the metal substrate. Therefore, it is also a great advantage that a display with high discharge efficiency can be obtained.
On the other hand, as a method of using a metal as a back plate which is one of the members for PDP, a method of covering the metal of the back plate with an insulating layer such as glass and using it as an auxiliary discharge electrode is disclosed in, for example, Japanese Patent Application Laid-Open No. 6-168669 ( In order to adjust the thermal expansion coefficient to the front plate glass, disclosed in Japanese Patent Application Laid-Open No. H10-260260, Ti is selected as the substrate for the back plate, and a method of processing the green ceramic tape on the partition wall by marking or embossing is, for example, It is disclosed as Japanese Patent Application Laid-Open No. 2001-526822 (see Patent Document 4).

Japanese Patent Laid-Open No. 3-205738 JP 2000-64027 A JP-A-6-168669 JP 2001-526822 A

As a result of examination of the above-described prior art by the present inventors, the method of electrodeposition of the manufacturing method disclosed in the above-mentioned Patent Document 1 has the advantage of using the above-mentioned metal, but has an insulating property. In general, the thickness of the layer is increased to 10 μm or more, and there is a problem that the aperture ratio of the cell is lowered.
Moreover, according to the vapor deposition of Al ₂ O ₃ of the manufacturing method disclosed in the above-mentioned Patent Document 2, although there is an advantage of using the above metal, there are many pinholes and cracks in the insulating film. It has been newly found that when a PDP is fabricated and discharged and driven, a leakage current flows through the partition walls, power consumption increases, and light emission efficiency decreases.
In addition, a metal partition wall formed by vapor deposition of Al ₂ O ₃ is an oxide layer having a single component composition, and the coefficient of thermal expansion cannot be controlled by the composition. In other words, the dielectric constant is inevitable, and further, the dielectric constant is low, for example, the electric capacity generated when electrically driving the PDP is increased, and a large voltage is required to drive the PDP, thereby reducing the power consumption of the PDP. It was a factor to increase.

Moreover, since the metal back plate disclosed in Patent Document 4 uses expensive Ti as a material, it leads to an increase in cost. Further, in the display devices disclosed in Patent Document 3 and Patent Document 4 described above, no means for controlling the thickness or improving the insulating property is provided for the insulating layer, and the performance as a display device ( Brightness and power consumption).
It is an object of the present invention to provide a pinhole which is a factor that hinders insulation characteristics even if a thin insulating layer is controlled to ensure an aperture ratio so as not to lower the luminance of display members such as metal partition walls and metal back plates. It is to provide a high-performance display member by imparting high insulating properties by reducing the number of cracks as much as possible.

When using metal for display members such as partition walls and back plates that partition cells, it is essential to insulate the metal substrate. To achieve this insulation, a high level of insulation is required. Technology is required.
Normally, when a thin insulating layer with a thickness of 10 μm or less is produced by a method such as vapor phase method or liquid phase method, which is excellent in mass productivity, a pinhole is affected by the surface defects of the metal substrate and the unevenness of the etched surface. As a result, cracks are likely to occur and the insulation is impaired. As a result of intensive studies on the composition and thickness of the insulating layer, the present inventor has reached the present invention.
That is, the present invention is a display member in which an oxide layer is formed on a metal substrate, the oxide layer containing P: 5 to 16% by mass, and the balance being silicon composed of Si and O The display member is made of an oxide and unavoidable impurities and has a thickness of 0.1 to 10 μm.
Further, the present invention is a display member formed by forming an oxide layer on a metal substrate, the oxide layer containing P: 5 to 16% by mass%, and further B: 15% or less by mass%. (0% is not included), and the balance is a silicon oxide composed of Si and O and inevitable impurities, and the thickness of the oxide layer is 0.1 to 10 μm. .

As an effect of the present invention, for example, the following effects can be obtained by taking, as an example, a partition that needs the most processing among the members for display.
(1) By using a metal for the partition wall, it is possible to avoid glass containing a large amount of harmful lead contained in the partition wall itself and dust at the time of production thereof, so that the environmental load can be greatly reduced.
(2) The metal substrate can be finely processed by etching. As a result, it is easy to improve the brightness by narrowing the partition wall width and increasing the aperture ratio and to increase the definition of the panel.
(3) Since deep hole processing can be performed as compared with a technique such as sandblasting, the discharge space can be widened, the discharge efficiency can be increased, and the power consumption can be reduced.
(4) By appropriately adjusting the composition of the oxide layer of the present invention, the insulating layer thickness can be easily controlled. As a result, it is possible to secure the aperture ratio of the cells in the partition wall and prevent a decrease in luminance.
For example, when the present invention is applied to the back plate, heat dissipation, thinness, light weight, and cost reduction can be realized as compared with the current glass.
Furthermore, even when applied to partition walls, back plates, and other various members, the oxide layer is softened by appropriate heat treatment together with appropriate composition adjustment of the oxide layer, Since cracks can be filled and insulation can be made perfect, it is extremely effective as a display member.

As described above, an important feature of the present invention is that a metal substrate is used to optimize the composition of the insulating material and the thickness of the insulating layer.
First, in the case of this invention, it is set as the member for setting it as a partition, a backplate, etc. using a metal substrate. Therefore, the structure, thickness, and shape of the metal substrate to be used are appropriately adjusted depending on the application. For example, in the case of a partition wall, fine through holes corresponding to display pixels are formed by a technique such as etching.
In the present invention, an oxide layer is formed on the above-described metal substrate.
As for the composition of the oxide layer, silicon oxide composed of Si and O is the main composition, and by adding P to this, it can be applied to the oxide insulating layer of the display member.
The purpose of P addition is to increase the thermal expansion coefficient of SiO ₂ of the main composition to bring it closer to the thermal expansion of the metal substrate, lower the softening point of SiO ₂ , and heat treatment process when assembling a display member as a display This is because the generation of cracks in the oxide layer is suppressed by the stress due to the difference in thermal expansion from the metal substrate.
If the amount added is too small, there is no effect of controlling the thermal expansion difference, and 5% or more is necessary in the present invention . If the addition amount is smaller than this, cracks are generated in the oxide layer by, for example, a heat treatment step when assembling the display. Moreover, even if there is too much addition amount, insulation will fall and the malfunction that a display will not display an image correctly will arise. Therefore, in the present invention, the upper limit is made 16% or less. A more preferable upper limit of the addition amount is 12%.

In the present invention, the reason why the balance is mainly composed of silicon oxide consisting essentially of Si and O is that the power consumption of the PDP is greatly reduced.
The dielectric constant of the SiO ₂ oxide layer is about 4. This is less than or equal to about 10 of the oxide composed of Al ₂ O ₃ proposed by the applicant of the present invention, and it is very difficult to suppress the electric capacity generated when the PDP is electrically driven. Since it is advantageous, the voltage can be kept low in order to drive the PDP, and the power consumption of the PDP can be reduced.
In the present invention, the balance is mainly composed of silicon oxide consisting essentially of Si and O. For example, when qualitative analysis or quantitative analysis is performed with an EDX (energy dispersive X-ray analyzer), P In addition, Si and O are detected, and the other means that the elements contained in the oxide layer are inevitably detected during and after the formation of the oxide layer.
In addition, when performing qualitative analysis or quantitative analysis with an analyzer such as EDX, the component of the metal substrate may be detected if the oxide layer is thin. Therefore, when performing quantitative analysis, exclude the component of the metal substrate. A quantitative analysis is recommended.

Next, the thickness of the oxide layer will be described.
Since the oxide layer of the present invention functions as an electrical insulating layer, the oxide layer needs to have a sufficient thickness as the electrical insulating layer. If the thickness of the oxide layer is less than 0.1 μm, the insulating property is low and the display cannot be normally driven. Therefore, the lower limit is set to 0.1 μm or more.
However, when the thickness of the oxide layer exceeds 10 μm, the cell aperture ratio decreases and the luminance of the display decreases. Therefore, the upper limit of the thickness of the oxide layer is set to 10 μm or less. The thickness of the oxide layer is more preferably 0.5 to 7 μm, but the suitable thickness differs slightly depending on where the display member is used. For example, if it is used for a partition, the oxide layer The preferable thickness is preferably about 0.3 to 5 μm so that the aperture ratio does not decrease. If the oxide layer is used for the back plate, the preferable thickness is 0.8 to 7 μm.
As described above, in the present invention, by using a metal member having an oxide layer whose main composition is silicon oxide consisting essentially of Si and O, the remainder reduces the power consumption of the PDP, By adding an appropriate amount of P to this, it is possible to reduce the pinholes and cracks of the oxide layer formed on the metal substrate as much as possible, and to adjust the thickness of the oxide layer within a specific range so as to have an insulating property. By optimizing the aperture ratio, an optimal display member can be realized.

In the oxide layer of the present invention, inevitable cracks and pinholes may occur slightly. Of course, compared with the Al ₂ O ₃ oxide layer already proposed by the present inventors, the number of silicon oxide and P is so small that it cannot be compared.
However, if pinholes or cracks remain in the oxide layer, there may still be problems in terms of insulation. Therefore, in the present invention, an appropriate amount of B can be added in order to reduce the slightly generated cracks and pinholes as much as possible.
The reason is that addition of B can lower the softening point of SiO ₂ . By performing heat treatment on the oxide layer to which an appropriate amount of B is added, inevitably generated pinholes and cracks can be filled, and as a result, insulation can be made more reliable.
In order to obtain this effect, it may be contained exceeding the B-free (B: 0%) level, but in order to obtain a remarkable effect, the B content should be added in the range of 1 to 15% by mass%. .
If B is less than 1%, the effect of softening the oxide layer is at the B-free level, or the effect of B addition is not clear just by slightly improving. On the other hand, even if B exceeds 15%, Not only is the effect of further softening the oxide layer not expected, but the upper limit is made 15% because it concentrates on the surface of the oxide layer and crystallizes as boric acid. Preferably it is 8 to 13% of range.

For the metal substrate of the present invention, for example, in the case of PDP, soda lime glass or high strain point glass having a thermal expansion coefficient of about 4 to 10 × 10 ⁻⁶ / ° C. is mainly used for the front plate and the back plate. It is desirable to refrain from using those having a coefficient of thermal expansion that is excessively different from those of these glasses.
The reason is that the metal substrate is used as a metal member on which an oxide insulating layer is formed and bonded to the front plate glass or the back plate glass of the display. For this reason, unless a metal material having a thermal expansion characteristic close to that of glass is used, the bonded portion is peeled off, the entire substrate is warped, a bonding failure occurs, and it is difficult to drive the display normally. Because.
Therefore, in the present invention, it is preferable to use an Fe—Ni-based alloy containing Ni: 40 to 55% in mass% in which the thermal expansion coefficient can be easily adjusted by the amount of Ni, as a preferable metal substrate material.
This is because the amount of Ni required to match the thermal expansion characteristics of the currently used glass (thermal expansion coefficient of a general glass substrate material: 4 to 10 × 10 ⁻⁶ / ° C.) is 40 to 40% by mass. This is because it is 55%.
Further, an Fe—Ni—Cr alloy in which a part of Ni is replaced with Cr, an Fe—Ni—Co alloy in which Co is similarly replaced, and the like can also be used.
Furthermore, inevitable impurities may be included so as not to increase the production cost as long as various characteristics of the metal substrate are not deteriorated.

Next, the manufacturing method of the display member of the present invention described above will be described.
First, in the present invention, an oxide layer is formed on a metal substrate. The formation method is not particularly limited as long as the composition and thickness of the oxide layer can be adjusted. For example, the formation method may be a CVD method suitable for high-speed and uniform film formation at low cost.
And the metal substrate in which the oxide layer was formed is heat-processed at 400-750 degreeC. By heat-treating at a temperature in this range, P: 1 to 16% is contained, and the remainder is an oxide layer mainly composed of silicon oxide composed of Si and O, and the oxide layer is softened. Insulation can be improved. In addition, the oxide layer containing an appropriate amount of B can fill pinholes and cracks inevitably generated by this heat treatment, and can further improve the insulation.
In the present invention, the upper limit of the heat treatment temperature is set to 750 ° C., and in the temperature range exceeding 750 ° C., the metal substrate is distorted and cannot be used as a display member. In order to give as little heat history as possible to the metal substrate, the lower the temperature of the heat treatment, the more preferably 600 ° C. is the upper limit.
Further, the lower limit of the heat treatment temperature is set to 400 ° C., and if the temperature is lower than 400 ° C., the insulating property of the oxide layer becomes insufficient. The minimum of the preferable heat processing temperature is 500 degreeC.
The heat treatment time is not particularly limited, but is preferably about 10 minutes to 2 hours, and is adjusted by the thickness of the oxide layer and the amount of B added to the oxide layer so that pinholes and cracks in the oxide layer are filled. It is good to hold.

The following examples further illustrate the present invention.
Fe-48Ni steel ingot containing 48% Ni by mass and obtained by vacuum melting, with the balance being substantially Fe and unavoidable impurities is subjected to hot and cold plastic working to obtain a thickness. A 0.2 mm plate was obtained.
A non-through hole serving as a discharge space of the display was provided in this plate material by etching, and the metal substrate was processed into the shape shown in FIG.
Then, the oxide layer of Table 1 was formed in the surface of the metal substrate, the back surface, and the hole wall surface by CVD method, and the metal partition with a metal back plate as a member for a display was produced.
The metal partition was heat-treated at 700 ° C. for 1 hour in the air to soften the oxide layer. A phosphor was applied to the metal partition wall having the oxide insulating layer, and then baked at 500 ° C.
And after joining and sealing with front plate glass at 450 degreeC, the exhaust_gas | exhaustion process was implemented at 400 degreeC. And the mixed gas of Ne and Xe was enclosed in the cell, the panel for plasma displays was produced, and the performance was evaluated.
The dielectric breakdown voltage was evaluated by measuring the dielectric breakdown voltage when a metal sphere was in contact with the front and back sides of the barrier rib and the AC voltage was gradually increased and applied in the flat portion of the barrier rib having an oxide insulating layer. It is a result.
The evaluation of the thermal cycle is as follows: ○ in the case where no crack was found in the oxide insulating layer under the heat treatment conditions of 500 ° C. × 1 hr in the atmosphere corresponding to the heat treatment at the time of assembling the panel; did.
The evaluation results are shown in Table 1.

The results of Table 1 will be described.
No. 1-No. 4, no. 1 is low in P content and has poor thermal cycle performance due to the problem of consistency of thermal expansion coefficient with the metal substrate, so that when the panel is assembled, the oxide insulating layer cracks, and the withstand voltage is low. Since it decreased, it could not be driven as a PDP.
No. of the present invention. 2 and No. In No. 3, the withstand voltage was 100 V or higher on one side, showing a good withstand voltage, and was able to be driven normally as a PDP.
No. Regarding No. 4, since the content of P was high, the withstand voltage was 100 V or less, and it was judged that practical application was difficult.

In addition, no. 5-No. 7, no. 6 and no. For No. 7, the addition of B resulted in No. It can be seen that the withstand voltage is improved as compared with FIG.
No. For No. 5, since the addition amount of B is small, the withstand voltage is No. 5. Stayed at 3rd level.
No. 8 and no. In No. 9, the P content is too little or too much. For No. 8, since the P content is low and the thermal cycle performance is poor due to the consistency of the thermal expansion coefficient with the metal substrate, cracks occur in the oxide layer when it is assembled into a PDP, and the withstand voltage is low. Since it decreased, it could not be driven as a PDP.
No. 9 could be driven as a PDP, but because the P content was high, the withstand voltage was 100 V or less, and when the power consumption was measured, it was determined to be abnormal and difficult to put into practical use.
No. No. 10 had a low withstand voltage due to the thin oxide layer, and could not be driven as a PDP.

  The present invention is a display member having a high insulation reliability using a metal substrate as a display member and using an oxide layer that is easily softened by heat treatment as an insulating layer and easily fills in pinholes and cracks. is there. In addition to display components, it can be applied to applications where fineness, strength, heat dissipation, and insulation are indispensable by microfabrication and deep hole machining, and the environmental impact can be greatly reduced when replacing glass components containing lead. .

It is a block diagram which shows an example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate for metal partition 2 Oxide insulating layer 3 Phosphor layer 4 Substrate for metal back plate 5 Glass front plate 6 Discharge space

Claims (2)

  A display member formed by forming an oxide layer on a metal substrate, the oxide layer containing P: 5 to 16% by mass, with the balance being silicon oxide composed of Si and O and unavoidable A display member comprising impurities and a thickness of the oxide layer of 0.1 to 10 μm. A display member formed by forming an oxide layer on a metal substrate, the oxide layer containing P: 5 to 16% by mass%, and further B: 15% or less (0% included) by mass% And the remainder consists of silicon oxide and inevitable impurities composed of Si and O, and the thickness of the oxide layer is 0.1 to 10 μm.

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