JP2001294850A - Fluorescent substance paste and plasma display panel using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a fluorescent substance paste having most suitable viscosity characteristics and a plasma display panel using the fluorescent substance paste in a method for producing the plasma display panel by applying the fluorescent substance paste to a partition while discharging the fluorescent substance paste from a nozzle, and to provide a method for producing the plasma display panel. SOLUTION: This fluorescent substance paste is characterized by having >=20 (Pa.s) viscosity characteristics at 1 (1/s) shear rate and <=8 (Pa.s) at 200 (1/s) shear rate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display panel used for a display device and the like, and more particularly to a phosphor paste used for a phosphor layer used for a plasma display panel, and a method and an apparatus for producing the phosphor layer.

[0002]

2. Description of the Related Art Conventionally, in order to apply a phosphor to a display device such as a CRT display or a plasma display panel, a phosphor paste dispersed or mixed with various organic materials, inorganic materials, etc. is used, and screen printing or the like is used. A phosphor layer is formed by the method.

Further, a manufacturing method of applying a phosphor paste while discharging the phosphor paste from a fine nozzle has been proposed.

[0004]

In the manufacturing method in which the phosphor paste is applied to the inside of the partition wall while being discharged from the nozzle, the viscosity characteristics of the phosphor paste used are important.

[0005] If the viscosity is too high when discharging from a nozzle, the dischargeability becomes unstable, causing clogging or bending of the discharge. In addition, when there are a plurality of nozzles, the discharge amount from each nozzle varies. In such a case, the formed phosphor layer has a non-uniform film thickness, resulting in a defective product.

On the other hand, it is necessary to form a desired shape of the phosphor paste after ejection in the partition. It is desirable that the film be formed on both the side wall and the bottom of the partition with the same thickness.

However, when the viscosity of the phosphor paste to be used is low, most of the phosphor paste flows down from the side wall without being formed on the side wall and accumulates at the bottom. Conversely, if the viscosity is high, most of the film is formed on the side wall, and the bottom film thickness is reduced.

[0008] Therefore, in a manufacturing method in which the phosphor paste is applied to the inside of the partition wall while being discharged from the nozzle, it is very important that the phosphor paste used has an optimum viscosity state.

The present invention has been made in view of these inconveniences. In a manufacturing method in which a phosphor paste is applied from a nozzle to a partition while discharging the paste from a nozzle, a phosphor paste having optimum viscosity characteristics and a phosphor paste having the same viscosity are provided. An object of the present invention is to provide a method of manufacturing a plasma display panel using a body paste, and a manufacturing apparatus used for manufacturing the plasma display panel.

[0010]

The phosphor paste according to the present invention has a viscosity characteristic of 20 when the shear rate is 1 (1 / s).
(Pa · s) or more and a shear rate of 200 (1 /
In the case of s), it is not more than 8 (Pa · s).

[0011] Further, there is provided a method of manufacturing a plasma display panel, wherein a phosphor layer is formed by using the phosphor paste and scanning along a partition while discharging from a nozzle between the partitions. .

In addition, a phosphor paste whose viscosity characteristic decreases with an increase in shear rate is applied by applying a stress such that the viscosity becomes 8 (Pa · s) or less when the phosphor paste is applied to the inside of the partition wall. Forming a plasma display panel.

[0013] Further, the invention is characterized in that the stress is applied when discharging from a fine nozzle.

Further, a plurality of the fine nozzles are provided,
It is characterized in that a continuous flow can be discharged at the same time.

Further, a phosphor paste whose viscosity characteristics decrease with an increase in the shear rate is applied by applying a temperature such that the viscosity becomes 8 (Pa · s) or less when the phosphor paste is applied to the inside of the partition wall. Is formed.

Further, a control means capable of controlling the temperature to a viscosity of 8 (Pa · s) or less when using a phosphor paste whose viscosity characteristics decrease with an increase in the shear rate and applying the phosphor paste to the inside of the partition wall is provided. An apparatus for manufacturing a plasma display panel, characterized in that:

Further, the phosphor paste contains a photosensitive component.

Further, the plasma display panel is manufactured by the manufacturing apparatus.

According to the phosphor paste of the present invention and the manufacturing method using the phosphor paste, it is possible to discharge stably from the nozzle and to form the phosphor layer in the partition into a stable shape. It is possible to form a high quality phosphor layer in a short time. Further, by using the substrate on which the phosphor layer is formed, there is an advantage that a highly reliable, high-quality display device or the like can be stably obtained.

The reason why the phosphor layer can be formed stably by the above means will be described below.

The phosphor paste used for coating the inside of the partition wall while discharging from the nozzle is prepared by dispersing and mixing phosphor powder and an organic component such as an organic solvent and a resin. The phosphor paste thus produced exhibits various viscosity characteristics depending on the organic solvent and resin used.

When a phosphor layer is formed by discharging from a nozzle, the phosphor paste to be used needs to have a so-called thixotropic property in which the viscosity changes depending on the force (shearing force) applied to the phosphor paste. The properties require that the viscosity decrease as the shear force increases.

In the case of discharging from a nozzle, if the viscosity of the phosphor paste used is high, the fluidity is impaired, resulting in defective discharge. However, after the discharge, if the viscosity is not high to some extent, on the other hand, all flow and the film cannot be formed on the side wall of the partition wall.

Further, when the phosphor paste passes through the nozzle, it passes through a narrow space at a high flow rate and receives a considerable shearing force. Thereafter, the applied shear force will be lost.

Therefore, the optimum viscosity characteristics of the phosphor paste used for coating the inside of the partition wall while discharging from the nozzle are that the viscosity is high on the low shear side and low on the high shear side. .

[0026]

FIG. 1 is a schematic diagram showing a change in viscosity of a phosphor paste according to the present embodiment with respect to a shear rate.

In the same figure, phosphor pastes having different viscosity characteristics are shown as comparative examples.

Table 1 shows the dischargeability of the phosphor paste according to the present embodiment shown in FIG. 1 from the nozzles.

[0029]

[Table 1]

FIG. 2 is a schematic diagram showing the cross-sectional shape of the phosphor layer when the phosphor paste having the characteristics of the present embodiment shown in FIG. 1 and (Table 1) is discharged from the nozzle and applied to the inside of the partition.

FIG. 3 is a schematic diagram showing the cross-sectional shape of the phosphor layer when the phosphor paste having comparative characteristics shown in FIG. 1 and (Table 1) is discharged from the nozzle and applied to the inside of the partition.

As shown in Comparative Example 1 in FIG.
Even when the viscosity at the time of (1 / s) is 20 (Pa · s) or more, the viscosity at the shear rate of 200 (1 / s) is 8 (Pa · s).
s) If it is more than this, as shown in (Table 1), the discharge property from the nozzle is poor, and it is impossible to apply the solution to the inside of the partition.

Further, as shown in Comparative Example 2 in FIG. 1, even when the viscosity at a shear rate of 200 (1 / s) is 8 (Pa · s) or less, the viscosity at a shear rate of 1 (1 / s) is low. Has a viscosity of 20
When the pressure is (Pa · s) or less, the ink can be discharged well from the nozzle as shown in (Table 1). However, as shown in FIG. It is almost impossible to form a phosphor layer on the side wall.

On the other hand, when the phosphor paste of the present invention shown in Example 1 in FIG. 1 is used, it is possible to discharge well from the nozzle, and even when applied to the inside of the partition wall, it does not flow down from the side wall, and It is possible to form a phosphor layer uniformly over the entire area.

[0035]

As described above, in the manufacturing method in which the phosphor paste according to the present invention is used in the manufacturing method in which the phosphor paste is applied from the nozzle while being discharged from the nozzle, stable discharge is possible and the phosphor layer in the partition is provided. Can be formed in a stable shape, and a high-quality phosphor layer can be formed in a short time. In addition, by using the substrate on which the phosphor layer is formed, a highly reliable, high-quality display device or the like can be stably obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a change in viscosity with respect to a shear rate in Comparative Examples 1 and 2 having different viscosity characteristics from Example 1 according to the present embodiment.

FIG. 2 is a schematic diagram showing a cross-sectional shape of a phosphor layer when the phosphor paste of Example 1 according to the present embodiment is applied to the inside of a partition wall while being discharged from a nozzle.

FIG. 3 is a schematic diagram showing a cross-sectional shape of a phosphor layer when the phosphor paste of Comparative Example 2, which is not based on the present embodiment, is applied to the inside of a partition wall while being discharged from a nozzle.

[Explanation of symbols]

 Reference Signs List 10 phosphor layer 11 partition 12 substrate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4H001 CA02 CC14 CF01 5C028 FF04 5C040 FA01 FA04 GA03 GG09 JA05 JA40 KB01 MA23

Claims (9)

[Claims] When the viscosity characteristic is a shear rate of 1 (1 / s),
20 (Pa · s) or more and a shear rate of 200
A phosphor paste characterized by being 8 (Pa · s) or less when (1 / s). 2. A method of manufacturing a plasma display panel, wherein a phosphor layer is formed by scanning along a partition while discharging the phosphor paste according to claim 1 from a nozzle between the partitions. . 3. A phosphor paste whose viscosity characteristic decreases with an increase in shear rate.
(Pa · s) A method for manufacturing a plasma display panel, comprising applying a stress having a viscosity of not more than (Pa · s) to form a phosphor layer. 4. The method according to claim 3, wherein said stress is applied when discharging from said fine nozzle. 5. The method according to claim 4, wherein a plurality of said fine nozzles are provided, and a continuous flow can be discharged at the same time. 6. A phosphor paste whose viscosity characteristic decreases with an increase in shear rate.
(Pa · s) A method for manufacturing a plasma display panel, wherein a phosphor layer is formed by applying a temperature so as to have a viscosity of not more than (Pa · s). 7. When applying the phosphor paste in the partition,
An apparatus for manufacturing a plasma display panel, comprising: control means capable of controlling a temperature at which the viscosity becomes 8 (Pa · s) or less. 8. The phosphor paste according to claim 1, wherein the phosphor paste contains a photosensitive component. 9. A plasma display panel manufactured by the manufacturing apparatus according to claim 7.