JP2001062378A - Cathode-ray tube production method, cathode-ray tube production apparatus, and liquid application method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent foams generated in a coating liquid in a coating liquid supply pipeline when temporal stop of the coating liquid discharge and restart of discharge are repeated from being applied together with a coating liquid to an object. SOLUTION: When a coating film is formed on the inner face of an object 2 by sweeping a coating liquid discharge part 7 discharging a coating liquid through a plurality of small holes, some of the coating liquid supplied to the inside of the coating liquid discharge part is continuously discharged to the outside of the coating liquid discharge part 7 through an air vent passage 72 and temporal stop of the coating liquid discharge out the coating liquid discharge part 7 and restart of discharge are repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a cathode ray tube, an apparatus for manufacturing a cathode ray tube, and a liquid coating method. The present invention relates to a method for manufacturing a cathode ray tube, a cathode ray tube manufacturing apparatus, and a liquid coating method capable of realizing a high fluorescent screen at a high level.

[0002]

2. Description of the Related Art A general cathode ray tube for a TV comprises a funnel-shaped cathode ray tube main body and a front glass made of transparent glass and covering the front surface of the cathode ray tube main body. The structure of the front glass is a deep dish having a moderately curved central surface and a frame-shaped outer peripheral wall erected on the outer periphery of the central surface. The end portion of the outer peripheral wall is joined to the front end surface of the cathode ray tube main body, and the cathode ray tube is assembled.

[0003] A phosphor layer is formed on the inner surface of the front glass, and an image can be displayed when the phosphor layer emits light by an electron beam irradiated from an electron gun. In a cathode ray tube for a color TV, a plurality of color phosphor layers are formed in a pattern such as a dot or a stripe.

In order to form a phosphor layer on the front glass, a phosphor slurry is supplied to the inner surface of the front glass by using a discharge means such as a nozzle, and the front glass is tilted and turned to form a phosphor coating film. After the formation of the phosphor coating film, an operation of drying and curing the phosphor coating film or forming the phosphor coating film in a predetermined pattern is performed.

[0005] As a means for discharging the phosphor slurry, a plurality of small holes are arranged in an axial direction on a liquid discharge arm crossing over the front glass, and the phosphor slurry is simultaneously supplied from the plurality of small holes into a curtain shape. A predetermined amount of the phosphor slurry is efficiently supplied to the entire inner surface of the front glass by causing the liquid discharge arm for discharging the phosphor slurry to move in parallel above the front glass while discharging the phosphor slurry in such a state. Methods and devices are known. In particular,
Japanese Patent Application No. 9-37548 filed by the present applicant earlier
No., Japanese Patent Application No. 10-77057, Japanese Patent Application No. 10-2646
No. 41 discloses a technique.

[0006]

However, the above-described method and apparatus for forming a phosphor screen have the following problems.

By opening and closing a pipe line for feeding the phosphor slurry into the phosphor slurry discharge section, the discharge of the phosphor slurry from the phosphor slurry discharge means is temporarily stopped.
The discharge can be restarted. However, when the phosphor slurry supply pipe is closed, cavitation occurs, and bubbles are generated in the phosphor slurry in the pipe. The bubbles generated in the phosphor slurry are supplied into the front glass together with the phosphor slurry when the discharge is restarted.
The bubble once supplied into the front glass causes a tail-like bubble unevenness when the front glass is tilted and turned thereafter, and there is a problem that a uniform phosphor coating film cannot be formed. Accordingly, the foam unevenness significantly deteriorates the quality performance of the cathode ray tube.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problem, and when the discharge of the coating liquid is temporarily stopped and restarted, the coating liquid is supplied into the coating liquid in the coating liquid supply pipe. Provided are a method of manufacturing a cathode ray tube, a cathode ray tube manufacturing apparatus, and a liquid coating method that realize uniform formation of a coating film without foam unevenness by preventing generated bubbles from being applied to an object together with a coating liquid. Is to do.

[0009]

In order to achieve the above object, the present invention is configured as follows.

According to the first aspect of the present invention, a phosphor slurry is applied to the inner surface of the front glass of a cathode ray tube on which a dot or stripe-shaped black matrix has been formed in advance, and exposure and development are performed, so that each color is interposed between the black matrices. In a method for manufacturing a cathode ray tube having a step of forming a phosphor,
When forming a phosphor coating film on the inner surface of the front glass by sweeping the coating liquid discharge unit having a plurality of small holes and discharging the phosphor slurry from the small holes by one-way operation or reciprocating operation in one direction, A discharge step of continuously discharging a part of the phosphor slurry supplied to the inside of the coating liquid discharge section to the outside of the coating liquid discharge section through an air vent passage; and A stop operation of temporarily stopping the discharge of the phosphor slurry, and a repetition step of repeating a discharge restart operation of restarting the discharge of the phosphor slurry from the small holes of the application liquid discharge unit after the stop. When performing the discharge resuming operation after the stopping operation in the repetitive step, bubbles generated in the phosphor slurry in the phosphor slurry supply pipe line, the phosphor slurry of the phosphor slurry With parts, to provide a method of manufacturing a cathode ray tube, characterized in that to perform the discharge step of continuously discharging to the outside of the coating solution discharge section through the air vent passage.

According to the second aspect of the present invention, when the coating liquid discharge section is swept in one direction by one-way operation or reciprocating operation to apply the phosphor coating film on the inner surface of the front glass, the air is released from the air vent passage. Of the phosphor slurry to be discharged, the discharge amount per unit time of the blue phosphor slurry or the green phosphor slurry is the blue phosphor slurry or the green phosphor slurry discharged from the whole of the plurality of small holes of the application liquid discharge unit. 3. The method for manufacturing a cathode ray tube according to the first aspect, wherein the discharge amount per unit time is 3 to 10%.

According to the third aspect of the present invention, when applying the phosphor slurry film to the inner surface of the front glass by sweeping the coating liquid discharge section in one direction by one-way operation or reciprocating operation, the coating liquid discharge section is discharged from the air vent passage. The cathode ray tube according to the first or second aspect, wherein a discharge amount per unit time of the red phosphor slurry to be discharged is 5 to 12% of a discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes. A manufacturing method is provided.

[0013] According to a fourth aspect of the present invention, in the repetition step, when the coating liquid discharge section passes above the outer peripheral wall of the front glass, the phosphor slurry from the coating liquid discharge section is discharged. The method for manufacturing a cathode ray tube according to any one of the first to third aspects, in which the discharge is temporarily stopped, is provided.

According to the fifth aspect of the present invention, the coating liquid discharge section having a plurality of small holes and discharging the coating liquid from the small holes is swept in one direction by one-way operation or reciprocating operation. In a liquid coating method for forming a coating film on a coating object by using a coating liquid, the coating liquid is formed by sweeping the coating liquid discharge section in one direction by one-way operation or reciprocating operation to form a coating film on the coating object. A step of continuously discharging a part of the coating liquid supplied to the inside of the discharge section to the outside of the coating liquid discharge section through an air vent passage, and temporarily discharging the coating liquid from the small hole of the coating liquid discharge section. And a repetition step of repeating a stop operation for temporarily stopping and a discharge resumption operation for resuming the application liquid discharge. When the discharge resumption operation is performed after the stop operation in the repetition step, the application liquid supply is performed. The discharging step of continuously discharging air bubbles generated in the coating liquid in the pipe, together with a part of the coating liquid, to the outside of the coating liquid discharge section through the air vent passage is performed. To provide a liquid application method.

According to a sixth aspect of the present invention, a phosphor slurry is applied to the inner surface of the front glass of a cathode ray tube on which a dot or stripe-shaped black matrix has been formed in advance, and exposure and development are performed, so that each color is interposed between the black matrices. In a cathode ray tube manufacturing apparatus having a step of forming a phosphor, a coating liquid discharge section having a plurality of small holes and discharging a phosphor slurry from the small holes is swept in one direction by a one-way operation or a reciprocating operation. When a phosphor coating film is formed on the inner surface of the front glass, a part of the phosphor slurry supplied to the inside of the coating liquid discharge part is continuously discharged to the outside of the coating liquid discharge part through an air vent passage. Mechanism and
A stop operation for temporarily stopping the discharge of the phosphor slurry from the small holes of the coating liquid discharge section, and after the stop, the discharge of the phosphor slurry from the small holes of the coating liquid discharge section is restarted again. And a control unit for repeatedly performing the discharge restart operation. When the discharge restart operation is performed after the stop operation in the control unit, the discharge mechanism causes the discharge slurry to generate in the phosphor slurry in the phosphor slurry supply pipe path. An apparatus for manufacturing a cathode ray tube, characterized in that the generated bubbles are continuously discharged together with a part of the phosphor slurry to the outside of the coating liquid discharge section through the air vent passage.

According to a seventh aspect of the present invention, when the control section sweeps the coating liquid discharge section in one direction by one-way operation or reciprocating operation to apply the phosphor coating film on the inner surface of the front glass, The discharge mechanism discharges a blue phosphor slurry or a green phosphor slurry per unit time of the phosphor slurry discharged from the air vent passage from the entire plurality of small holes of the application liquid discharge unit. The cathode ray tube manufacturing apparatus according to the sixth aspect, wherein the discharge amount of the blue phosphor slurry or the green phosphor slurry per unit time is controlled to be 3 to 10%.

According to an eighth aspect of the present invention, when applying the phosphor slurry film to the inner surface of the front glass by sweeping the coating liquid discharge unit in one direction by one-way operation or reciprocating operation by the control unit. The discharge mechanism is configured such that the discharge amount per unit time of the red phosphor slurry discharged from the air vent passage is 5 to 12% of the discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes. A cathode ray tube manufacturing apparatus according to the sixth or seventh aspect for controlling.

[0018] According to a ninth aspect of the present invention, when the coating liquid discharge section passes above the outer peripheral wall of the front glass, the control section controls the phosphor slurry from the coating liquid discharge section. Sixth to control to temporarily stop discharge
8. A cathode ray tube manufacturing apparatus according to any one of the eighth to eighth aspects.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing a cathode ray tube manufacturing apparatus used in a method for manufacturing a cathode ray tube according to one embodiment of the present invention, and FIG. 2 is a view showing the cathode ray tube manufacturing used in the method for manufacturing a cathode ray tube according to the embodiment of the present invention. FIG. 2 is a partially cutaway side view of the device.

In FIG. 1, a cathode ray tube manufacturing apparatus 1 used in a method of manufacturing a cathode ray tube comprises a holding unit 3 for holding a front glass 2 of a 51 cm size cathode ray tube having an aspect ratio of 4: 3, for example, and a coating unit. 4 and a coating liquid recovery tank 6.

As shown in FIG. 2, the front glass 2 has a central surface portion 21 whose gently curved planar shape is substantially rectangular.
And an outer peripheral wall 20 erected on the outer periphery of the central surface portion 21. The central surface 21 may be substantially flat with little curvature. The central surface portion 21 and the outer peripheral wall 20 of the front glass 2 may be integrally formed, or may be formed by integrally joining separately manufactured members.

The holding portion 3 is provided with a central surface portion 21 of the front glass 2.
2, that is, the concave inner surface in FIG. 2 is held upward. At the bottom of the holding part 3, there is provided a turning part 30 having a rotation drive device such as a motor, and the holding part 3 is turned by driving the turning part 30.

The coating unit 4 is a horizontal-bar-shaped coating liquid discharge unit 7 that is horizontally arranged across the space above the front glass 2 accommodated in the holding unit 3, and supports the coating liquid discharge unit 7 to perform coating. A moving unit 8 that translates in a direction perpendicular to the longitudinal axis of the liquid discharging unit 7; Although only one coating unit 4 is shown in the figure for simplicity, one coating unit 4 applies a phosphor slurry of only one of blue, green, and red. , Blue, green, and red are applied, and a phosphor slurry of each color is applied from the application unit 4 for each color.

A moving unit 8 for moving the coating liquid discharging unit 7 in parallel
In a pair of guide rails 80, 80 arranged in parallel at a predetermined interval with the holding unit 3 interposed therebetween, end members 82, 83 holding both ends of the application liquid discharging unit 7 are slidably supported respectively. It is configured. A ball screw shaft 81 penetrates one end member 82 of the end members 82 and 83 and is screwed with an internal nut portion. Ball screw shaft 81
Is located near one of the guide rails 80.
It is arranged parallel to 0 and rotatable forward and backward. By rotating the rotation axis of the motor 84 attached to one end of the ball screw shaft 81 in the forward and reverse directions, the ball screw shaft 81 was rotated in the forward and reverse directions, and was screwed into the ball screw shaft 81 with the forward and reverse rotation of the ball screw shaft 81. The end member 82 is a ball screw shaft 81
Move back and forth along the axial direction of. The opposite end member 83 integrated with the end member 82 via the application liquid discharge section 7
Also slide with respect to the other guide rail 80. As a result, the application liquid discharge section 7 can move in parallel above the front glass 2 by driving the motor 84 while being guided by the guide rails 80, 80.

A coating liquid supply pipe 85 is attached to an end member 83 holding one end of the coating liquid discharge section 7.
Through the coating liquid supply pipe 85, the phosphor slurry tank 10
0 to flow control valve 1 such as pump 101 and ball valve
The phosphor slurry is supplied to the inside of the coating liquid discharge unit 7 through the liquid supply unit 02.

FIG. 3 is a view of the application liquid discharge section 7 as viewed from below.
A plurality of small holes 71,.
1 are provided at predetermined intervals. The phosphor slurry supplied from the coating liquid supply pipe 85 into the coating liquid discharge section 7 is discharged simultaneously from all the small holes 71,.
As shown in FIG. 1, an air vent passage 7 composed of a flexible hose or the like is provided substantially in the center of the upper portion of the application liquid discharge section 7.
2 and an air vent passage opening / closing means 73 provided in the middle of the air vent passage 72 to constitute a discharge mechanism 150. As the air vent passage opening / closing means 73, for example, a ball valve that can open and close the air vent passage 72 and adjust the flow rate is used. The hydraulic pressure loss in the air vent passage 72 is sufficiently smaller than the hydraulic pressure loss in the small holes 71,. Specifically, as shown in FIG. 6, the inside diameter of the air vent passage 72 may be set to be sufficiently larger than the inside diameter of the small hole 71 of the application liquid discharge unit 7. As described above, the liquid pressure loss of the air vent passage 72 is reduced by the small holes 71 and
, 71, the air existing inside the application liquid discharge section 7 can be easily discharged to the outside through the air vent passage 72.

The coating liquid recovery tank 6 is arranged outside the front glass 2 and on one side of the front glass 2. As shown in FIG. 2, the coating liquid ejection unit 7 before the coating operation is
, 70 are discharged from the small holes 71,..., 71 at a position A above the coating liquid recovery tank 6 outside the tank. The discharged phosphor slurry 70, ..., 70
Is collected in the coating liquid collection tank 6. In this embodiment, one end of the air vent passage 72 is fixed inside the application liquid recovery tank 6 as shown in FIG.

The manufacturing process of the cathode ray tube will be described below with reference to FIGS. 1 to 5 based on the cathode ray tube manufacturing apparatus used in the method of manufacturing the cathode ray tube according to the above-described embodiment of the present invention. I do.

First, in step S1, a dot or stripe-shaped black matrix is formed on the inner surface of a front glass 2 having a size of 51 cm as an example by using a photolithographic method.

Subsequently, as an example, 25% by weight of a blue phosphor (particle size: 7 μm, manufactured by Nichia Chemical Industry), 2.5% by weight of polyvinyl alcohol (Poval B-24 manufactured by Denka), ammonium bichromate (nichrome acid manufactured by Kanto Chemical Co., Ltd.) Ammonium) A composition comprising 0.25 wt%, a surfactant 0.04 wt%, a dispersant 0.02 wt%, and deionized water is stirred and suspended by a stirrer such as a mixer or a disperser, and has a viscosity coefficient of 20 mPa · s. The blue phosphor slurry was prepared and held in a blue phosphor slurry tank, for example, the phosphor slurry tank 100 of FIG. Further, an aqueous ammonia solution was dropped into the blue phosphor slurry in the blue phosphor slurry tank 100 to adjust the pH of the blue phosphor slurry to 8.0.

Next, in step S2, the pump 10
1 to drive the flow control valve 102 and the coating liquid supply pipe 85
, The blue phosphor slurry is sent from the inside of the blue phosphor slurry tank 100 to the coating liquid discharge section 7, and the blue phosphor slurry is discharged from the small holes 71,..., 71 of the coating liquid discharge section 7. Subsequently, the supply amount of the blue phosphor slurry fed into the application liquid discharge section 7 is adjusted by the flow rate adjustment valve 102, and the flow rate of the air release passage 72 is adjusted by a ball valve as an example of the air release passage opening / closing means 73. That is, as an example, when the blue phosphor slurry is continuously discharged from the small holes 71,..., 71 of the coating liquid discharge unit 7, the plurality of small holes 71,
, 71, blue phosphor slurry 70, ..., discharged from
The total discharge flow rate of 70 is adjusted to 800 cc / min, and the amount of the blue phosphor slurry discharged into the coating liquid recovery tank 6 through the air vent passage 72 is adjusted to 50 cc / min. As described above, the plurality of small holes 7
When the blue phosphor slurry is discharged from 1, 71, ..., a part of the blue phosphor slurry can be continuously discharged from the air vent passage 72 having a smaller liquid pressure loss than the small holes 71, ..., 71. I have to. Next, the flow control valve 1
02 is closed to temporarily stop the discharge of the blue phosphor slurry from the application liquid discharge unit 7 for a predetermined time. After the stop operation is completed, the flow rate control valve 102 is opened and the above-described operation from the application liquid discharge unit 7 is performed again. The discharge resuming operation for resuming the discharge of the phosphor slurry is repeated a predetermined number of times to perform the coating on the inner surface of the front glass 2. Incidentally, the air vent passage opening / closing means 73 is always in an open state, and when the slurry discharge from the small holes 71, ..., 71 is stopped, a very small amount is generated due to the residual liquid pressure inside the coating liquid discharge part 7. There is continuous air vent passage 7
Discharge of the phosphor slurry from 2 occurs. Therefore, even when the discharge from the small holes 71,..., 71 is stopped, the bubble removal can be continuously performed.

The above step S2 is, specifically, the following 2-1 step S21 to 2-8 step S2
8 is performed.

That is, as a 2-1 step S21, the coating solution discharge section 7 is placed at a position (position A in FIG. 2) immediately above the coating solution recovery tank 6 so that the blue phosphor slurries 70,.
When 0 is discharged, the supply of the blue phosphor slurry to the application liquid discharge section 7 is shut off. This shutoff is performed by the flow control valve 102.
As an example, the opening and closing means such as a ball valve provided in the application liquid supply pipe 85 can be closed. By this blocking operation, the small holes 71,.
The discharge of the blue phosphor slurry from 1 is stopped.

Subsequently, as a 2-2 step S22,
By driving the motor 84 of the moving section 8,
Are moved from the position A to the position of one end inside the front glass 2 (position B in FIG. 2) while the discharge of the blue phosphor slurry from the small holes 71,.

The second to third steps S23 include the flow control valve 1
By opening the ball valve as an example of 02, the supply of the blue phosphor slurry to the application liquid discharge unit 7 moved to the position B is restarted, and the small holes 71,.
The discharge of the blue phosphor slurry 70,...

In the second to fourth steps S24, the application liquid ejecting section 7 which has resumed ejection is moved from the position B to the inside of the front glass 2 at a speed of 200 mm / sec by driving the motor 84 of the moving section 8. Sweep is performed to the end position (position C in FIG. 2), and the blue phosphor slurry is applied to the inner surface of the front glass 2 in the outward path.

Subsequently, as a 2nd-5th step S25,
The application liquid discharging unit 7 is driven by the reverse drive of the motor 84 of the moving unit 8.
Is made a U-turn, that is, moved in the direction opposite to the moving direction of the forward path, and is swept from the position C to the position B at the same speed of 200 mm / sec as the sweep rate of the forward path.
Is further overlapped on the blue phosphor slurry applied on the outward path, and the blue phosphor slurry is applied on the return path.

When the application liquid ejecting section 7 returns to the position B, the application operation is again performed by closing the opening / closing means such as a ball valve as an example of the flow control valve 102 in the second to sixth step S26. The supply of the blue phosphor slurry to the liquid discharge section 7 is shut off, and the discharge of the blue phosphor slurry from the small holes 71, ..., 71 is stopped.

In step 2-27, the application liquid discharging section 7 in which the discharge of the blue phosphor slurry is stopped is moved to the above B
From the position to the position A just above the coating liquid recovery tank 6.

Finally, as a 2nd-8th step S28, the supply of the blue phosphor slurry to the application liquid discharge section 7 which has returned to the position A is resumed, and the discharge of the blue phosphor slurry is resumed from the small holes 71,. I do.

After the 2-8 step S28, the process returns to the 2-1 step S21 again. After the cathode ray tube is carried out for the next step, another cathode ray tube is carried in and the other cathode ray tube is carried out. To start the application operation of the blue phosphor slurry of the above, or,
The front glass 2 is relatively arranged along the longitudinal direction of the coating solution discharge section 7.
Is moved to apply the blue phosphor slurry to another portion inside the front glass 2.

As described above, according to the above embodiment, when the blue phosphor slurry is applied, the small holes 71,.
Since a part of the blue phosphor slurry is continuously discharged from the air vent passage 72 having a smaller liquid pressure loss than
2-1 step S21 and 2-3 step S23, and 2-6 step S26 and 2-8 step S2
In 8, when the supply of the blue phosphor slurry is interrupted and resumed, bubbles generated in the blue phosphor slurry by cavitation are easily removed from the air vent passage 72 to the coating liquid recovery tank 6 together with a part of the blue phosphor slurry. Can be prevented from being generated, and it is possible to prevent the occurrence of bubble unevenness that has occurred when the bubbles are applied to the inner surface of the front glass 2 without being discharged. Further, when the application liquid discharge section 7 passes above the outer peripheral wall 20, the discharge of the blue phosphor slurry from the small holes 71, ..., 71 is stopped, and there is no shielding material covering the outer peripheral wall 20. This also has a new effect that the outer peripheral wall 20 is not stained with the blue phosphor slurry.

The amount of the blue phosphor slurry discharged through the air vent passage 72 per unit time is 3 to 10% of the total discharge amount per unit time discharged from the plurality of small holes 71,. Is desirable. When the ratio greatly exceeds 10%, when the discharge of the blue phosphor slurry is restarted, the blue phosphor slurry is vigorously discharged from the air vent passage 72 side, the discharge of the liquid from the application liquid discharge unit 7 becomes weak, and the liquid jumps out. I do. If it is 3% or less, the air bubbles are not sufficiently discharged through the air vent passage 72, and a bubble unevenness defect of 0.67% occurs.

As described above, after the blue phosphor slurry is applied to the inner surface of the front glass 2 in step S2, the holding section 3 is tilted and turned in step S3 to sufficiently remove the blue phosphor particles. The sedimentation is settled, and excess moisture is dried using a far infrared heater.

Further, in step S4, the dried coating film 74 is exposed to ultraviolet light through a shadow mask, developed by washing with water or the like, and a blue fluorescent light is applied to a predetermined position between the black matrices on the inner surface of the front glass 2. Form body dots.

Similarly, in steps S5 to S7, instead of the blue phosphor, a green phosphor (particle diameter of green phosphor manufactured by Nichia Corporation of 7 μm, viscosity coefficient of green phosphor slurry of 20 mPa · s) is used. Use step S2
The same operation as in S4 is performed to form green phosphor dots at predetermined positions on the front glass 2 between the black matrices.

Thereafter, similarly, in steps S8 to S10, instead of the green phosphor, a red phosphor (particle diameter of red phosphor manufactured by Nichia Corporation 6 μm, viscosity coefficient of red phosphor slurry 25 mPa · s) is used. Step S using
The same operation as in steps S2 to S4 is performed to form red phosphor dots at predetermined positions on the front glass 2 between the black matrices.

When the green phosphor slurry is applied, the amount of the green phosphor slurry discharged per unit time through the air vent passage 72 per unit time is the same as that of the blue phosphor slurry because its viscosity coefficient is almost the same. For some reason,
The discharge amount is set to 3 to 10% of the total discharge amount per unit time discharged from the plurality of small holes 71,. Also, when applying the red phosphor slurry, the amount of the red phosphor slurry discharged per unit time through the air vent passage 72 has a viscosity coefficient which is smaller than that of the blue phosphor slurry or the green phosphor slurry. Because of its high height, a plurality of small holes 71,
…, 71 of the total discharge amount per unit time discharged from 5
Set to 12%. The higher the viscosity coefficient, the more difficult it is to discharge air bubbles. Therefore, the discharge amount is set to be larger than in the case of the blue phosphor slurry or the green phosphor slurry. By setting as such, when the discharge of the red phosphor slurry is resumed, similarly to the blue phosphor slurry or the green phosphor slurry, the red phosphor slurry is vigorously discharged from the air vent passage side, and the coating liquid discharge unit It is possible to reliably prevent the liquid from being weakly ejected from causing the liquid to fly laterally, or to prevent the bubbles from being sufficiently discharged through the air vent passage, thereby causing a non-uniformity of, for example, 0.67%. In addition, the phosphor used at this time may be one coated with a pigment of the same color so as to absorb light of another color and reflect only its own color, and the particle diameter of the phosphor is also limited to this. Not something.

Thus, in steps S2 to S10, blue phosphor dots, green phosphor dots, and
After forming red phosphor dots at predetermined positions between the black matrices on the front glass 2, step S
At 11, a metal back layer is formed by aluminum deposition via a lacquer film.

Subsequently, in step S12, the front glass 2 on which the phosphor has been formed and the funnel are joined by a glass frit, an electron gun is sealed, and a cathode ray tube is manufactured by vacuum evacuation.

At this time, the phosphor coating film 74 formed on the inner surface of the front glass 2 can be formed into a uniform film without foam unevenness even if the supply of the phosphor slurry is interrupted and restarted. As an example, the foam unevenness defective rate has been reduced from 1.56% to 0.18%). Also, as an example, as a result of measuring the luminance of the manufactured cathode ray tube, a high luminance (a peripheral luminance distribution average value of 97%,
Worst value 95%) and stable color difference (3/1000 in x direction, y
Direction 5/1000).

According to the above-described embodiment, when applying the phosphor coating film 74 to the inner surface of the front glass 2 by sweeping the coating liquid discharging section 7 in one direction by one-way operation or reciprocating operation, A step of continuously discharging a part of the phosphor slurry supplied to the inside of the section 7 to the outside of the coating liquid discharge section 7 through the air vent passage 72; and a step of discharging the phosphor slurry from the coating liquid discharge section 7. A stop operation for temporarily stopping the discharge of the phosphor slurry from the application liquid discharge unit 7 and a discharge for restarting the discharge are included by including a step of repeating a stop operation for temporarily stopping the discharge and a discharge restart operation for restarting the discharge. Even if coating is performed by repeating the restarting operation, a uniform phosphor screen without bubble unevenness can be realized at a high level. Therefore, its practical effects are significant.

That is, when the discharge of the phosphor slurry from the application liquid discharge section 7 is temporarily stopped and restarted by opening and closing a pipe line for supplying the phosphor slurry, the supply of the phosphor slurry for cavitation is repeated. Bubbles are generated in the phosphor slurry in the pipe passage, and the generated bubbles are transferred to the plurality of small holes 71,.
By continuously discharging the coating liquid together with the coating liquid from the air vent passage 72 provided separately from the coating liquid discharge section 7, it is possible to form a uniform coating film without bubble unevenness.

At this time, if the liquid pressure loss in the air vent passage 72 is made sufficiently smaller than the liquid pressure loss in the small holes of the coating liquid discharge section, the air present inside the coating liquid discharge section through the air vent path can be further reduced. It can be discharged easily and more reliably to the outside. Specifically, the inside diameter of the air vent passage may be set to be sufficiently larger than the inside diameter of the small hole of the application liquid discharge section. Therefore, even when bubbles are generated in the phosphor slurry when the discharge of the phosphor slurry from the application liquid discharge unit is temporarily stopped and restarted, the bubbles are applied to the inner surface of the front glass together with the phosphor slurry. Since there is no such phenomenon, there is no occurrence of tailing-like coating unevenness due to bubbles when the front glass is tilted and swirled after the coating, and it is possible to realize a phosphor screen with a uniform coating pattern with high accuracy. The discharge amount of the phosphor slurry per unit time discharged from the air vent passage is 10% of the discharge amount per unit time of the phosphor slurry discharged from the plurality of small holes of the application liquid discharge unit.
It is desirable that it is less than about. If the ratio greatly exceeds 10%, when the discharge of the phosphor slurry is restarted, the phosphor slurry flows out vigorously from the air vent passage side, and the liquid discharge from the application liquid discharge section is weakened, causing a liquid side jump.

It should be noted that the present invention is not limited to the above embodiment, but can be implemented in various other modes.

For example, in the present embodiment, a cathode ray tube having a size of 51 cm has been described as an example. However, the present invention is not limited to this. The sweep speed of the discharge unit 7 can be freely adjusted.

In this embodiment, a specific example of reciprocal coating has been described.
Needless to say, it is also possible to set up and perform one-way application.

Further, in the present embodiment, when the application liquid discharging section 7 is U-turned in the coating operation, the coating liquid discharging section 7 is not moved in the longitudinal direction. It is also possible to move the application liquid ejecting unit 7 by about a half pitch of the hole arrangement intervals of the small holes 71,..., 71 when the U-turn position is reached. In this manner, the coating films 70 can be formed at intervals smaller than the intervals between the small holes 71,..., 71, and a more uniform coating film can be efficiently formed.

As shown in FIG. 7, in the above-described apparatus of FIG. 1, a control unit 200 is further provided.
The motor 84 of the moving unit 8, the air vent passage opening / closing means 73 of the discharge mechanism 150, the flow control valve 102, the pump 10
1. Connecting the swirling unit 30 and the like so that each operation can be controlled,
, 71 from the phosphor slurries 70,.
, A discharge operation for temporarily stopping the discharge of the phosphor slurries 70,... 70 from the small holes 71,. May be controlled to automatically and repeatedly operate. It should be noted that the discharge mechanism 150
Bubbles generated in the phosphor slurry in the phosphor slurry supply piping, together with a part of the phosphor slurry,
The operation of continuously discharging the coating liquid to the outside of the application liquid discharge section 7 through the air release passage 72 is performed by adjusting the opening / closing degree of a ball valve as an example of the air release passage opening / closing means 73 of the discharge mechanism 150 by the control section 200 and then constantly. , Can be performed by leaving it in an open state.

In the present embodiment, the phosphor slurry is applied to the inner surface of the front glass 2 of the cathode ray tube. However, other than the front glass 2, a member having a similar structure and coated with various coating liquids can be used. If available, they can be used.

Further, the object to be coated may have a substantially flat plate shape without the outer peripheral wall 20.

Therefore, the present invention can be applied not only to a cathode ray tube but also to a liquid coating method for forming a thin film by coating a liquid on an object to be coated such as a semiconductor substrate, a liquid crystal substrate, and an optical disk substrate. Needless to say.

[0064]

As described above, according to the method for manufacturing a cathode ray tube according to the first aspect of the present invention, a stop operation for temporarily stopping the discharge of the phosphor slurry from the coating liquid discharge section, and a stop operation after the stop. Even when the discharge resuming operation for resuming the discharge of the phosphor slurry is repeated, bubbles are generated in the phosphor slurry in the phosphor slurry supply pipe line due to cavitation. The coating liquid can be discharged to the outside of the coating liquid discharge section together with the coating liquid from the air vent passage provided separately from the plurality of small holes of the section, and a uniform fluorescent screen without bubble unevenness can be realized with high accuracy. .

According to the method of manufacturing a cathode ray tube according to the second aspect of the present invention, in addition to the operation and effect of the first aspect, when the phosphor slurry is a blue phosphor slurry or a green phosphor slurry, the air vent is performed. The blue phosphor slurry or the green phosphor slurry of the phosphor slurry discharged from the passage is discharged per unit time from the blue phosphor slurry or the green phosphor discharged from the plurality of small holes of the application liquid discharge unit. The discharge amount of body slurry per unit time is 3 ~
By setting the ratio to 10%, when the discharge of the blue phosphor slurry or the green phosphor slurry is restarted, the blue phosphor slurry or the green phosphor slurry is discharged from the air vent passage side vigorously. The liquid discharge from the liquid discharge part weakens and the liquid side jump occurs, or
It is possible to reliably prevent the bubbles from being sufficiently exhausted through the air vent passage, and to cause, for example, a defect of the foam unevenness of 0.67%.

According to the method of manufacturing a cathode ray tube according to the third aspect of the present invention, in addition to the effects of the first or second aspect, when the phosphor slurry is a red phosphor slurry,
Because the viscosity coefficient of the red phosphor slurry is higher than the viscosity coefficient of the blue phosphor slurry or the green phosphor slurry,
The higher the viscosity coefficient, the more difficult it is to discharge air bubbles. Therefore, the discharge amount is set to be larger than in the case of the blue phosphor slurry or the green phosphor slurry. Therefore, the discharge amount per unit time of the red phosphor slurry discharged from the air vent passage is set to be 5 to 12% of the discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes. Due to this, when the discharge of the red phosphor slurry is restarted, the red phosphor slurry will be discharged vigorously from the air vent passage side, the liquid discharge from the application liquid discharge section will be weakened, and the liquid horizontal jump will occur. Alternatively, it is possible to reliably prevent the bubbles from being exhausted sufficiently through the air vent passage, thereby causing, for example, a bubble unevenness defect of 0.67%.

According to the method of manufacturing a cathode ray tube according to the fourth aspect of the present invention, in addition to the functions and effects of any one of the first to third aspects, the coating liquid discharge section is provided above the outer peripheral wall of the front glass. During the passage, the discharge of the phosphor slurry from the small holes is stopped, so that the outer peripheral wall is not stained with the phosphor slurry even if there is no shielding material covering the outer peripheral wall.

According to the liquid application method according to the fifth aspect of the present invention, the stop operation for temporarily stopping the application liquid discharge from the application liquid discharge section, and the discharge restart for restarting the discharge of the coating liquid after the stop are performed. Even if the above operation is repeated, bubbles are generated in the coating liquid in the coating liquid supply pipe line due to cavitation, and the generated bubbles are evacuated by air vents provided separately from the plurality of small holes of the coating liquid discharge section. The coating liquid can be discharged from the passage to the outside of the coating liquid discharge section together with the coating liquid, and a uniform coating film without bubble unevenness can be formed.

According to the cathode ray tube manufacturing apparatus of the sixth aspect of the present invention, the coating liquid discharge section having a plurality of small holes and discharging the phosphor slurry from the small holes can be operated in one direction or reciprocally in one direction. When the phosphor coating film is formed on the inner surface of the front glass by being swept by the operation, a part of the phosphor slurry supplied to the inside of the coating liquid discharging unit is continuously discharged to the outside of the coating liquid discharging unit through an air vent passage. The control unit includes a discharge operation for temporarily discharging the phosphor slurry from the application liquid discharge unit, and a discharge restart operation for restarting the discharge of the phosphor slurry again after the discharge. Even if the above is repeated, bubbles are generated in the phosphor slurry in the phosphor slurry supply pipe line due to cavitation, and the generated bubbles are discharged by the discharge mechanism described above. From a plurality of air vent passages provided separately from the stoma, it can be discharged together with the coating liquid to the outside of the coating solution discharge section, no bubbles unevenness, can be realized at a high homogeneous phosphor screen precision.

According to the cathode ray tube manufacturing apparatus of the seventh aspect of the present invention, in addition to the effect of the sixth aspect, when the phosphor slurry is a blue phosphor slurry or a green phosphor slurry, the air vent passage The amount of blue phosphor slurry or green phosphor slurry discharged from the phosphor slurry per unit time per unit time is the blue phosphor slurry or green phosphor discharged from the plurality of small holes of the application liquid discharge unit. 3 to 1 of the discharge amount of the slurry per unit time
By setting the ratio to 0%, when the discharge of the blue phosphor slurry or the green phosphor slurry is resumed, the blue phosphor slurry or the green phosphor slurry is discharged from the air vent passage side vigorously. The liquid discharge from the liquid discharge section is weakened, causing a liquid side jump, or bubbles are not sufficiently discharged through the air vent passage.
Occurrence of bubble unevenness of 67% can be reliably prevented.

According to the cathode ray tube manufacturing apparatus of the eighth aspect of the present invention, in addition to the functions and effects of the sixth or seventh aspect,
When the phosphor slurry is a red phosphor slurry, since the viscosity coefficient of the red phosphor slurry is higher than the viscosity coefficient of the blue phosphor slurry or the green phosphor slurry, the higher the viscosity coefficient, the less bubbles are discharged. Because, compared to the case of blue phosphor slurry or green phosphor slurry,
Set a higher emission amount. Therefore, the discharge amount per unit time of the red phosphor slurry discharged from the air vent passage is set to be 5 to 12% of the discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes. Due to this, when the discharge of the red phosphor slurry is restarted, the red phosphor slurry will be discharged vigorously from the air vent passage side, the liquid discharge from the application liquid discharge section will be weakened, and the liquid horizontal jump will occur. Alternatively, it is possible to reliably prevent the bubbles from being exhausted sufficiently through the air vent passage, thereby causing, for example, a bubble unevenness defect of 0.67%.

According to the cathode ray tube manufacturing apparatus of the ninth aspect of the present invention, in addition to the functions and effects of any one of the sixth to eighth aspects, the coating liquid discharge section passes above the outer peripheral wall of the front glass. At this time, the discharge of the phosphor slurry from the small holes is stopped, so that the outer peripheral wall is not stained with the phosphor slurry even if there is no shielding material covering the outer peripheral wall.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a cathode ray tube manufacturing apparatus used in a method of manufacturing a cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a partially cutaway view of a side surface of a cathode ray tube manufacturing apparatus used in the cathode ray tube manufacturing method according to the embodiment of the present invention.

FIG. 3 is a bottom view of a coating liquid discharge unit in the cathode ray tube manufacturing apparatus used in the cathode ray tube manufacturing method according to the embodiment of the present invention.

FIG. 4 is a flowchart showing steps of a method for manufacturing a cathode ray tube according to the embodiment of the present invention.

FIG. 5 is a flowchart showing details of a repetitive operation of a discharge / stop operation and a discharge restart operation of the phosphor slurry in the method of manufacturing the cathode ray tube of FIG. 4;

FIG. 6 is a schematic cross-sectional view of a coating liquid discharge unit in a cathode ray tube manufacturing apparatus used in the cathode ray tube manufacturing method according to the embodiment of the present invention.

FIG. 7 is a block diagram of a control part of a cathode ray tube manufacturing apparatus used in a method of manufacturing a cathode ray tube according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cathode ray tube manufacturing apparatus, 2 ... Front glass, 3 ... Holding part,
Reference numeral 4 denotes a coating unit, 6 denotes a coating liquid recovery tank, 7 denotes a coating liquid discharge unit, 8 denotes a moving unit, 20 denotes an outer peripheral wall, and 21 denotes a central surface portion.
... Swirl part, 70 ... Phosphor slurry, 71 ... Small hole, 72 ...
Air vent passage 73, Air vent passage opening / closing means 74 74 Coating film 80 Guide rail 81 Ball screw shaft 82
... End member, 83 ... End member, 84 ... Motor, 85 ... Coating liquid supply pipe, 100 ... Phosphor slurry tank, 101 ... Pump, 102 ... Flow control valve, 150 ... Discharge mechanism, 200
... Control unit.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Nobuyuki Aoki 1-1, Sakaicho, Takatsuki-shi, Osaka F-term (reference) 4D075 AC06 AC84 AC88 AC94 CA47 DA06 DB13 DC19 EA31 5C028 HH04

Claims (9)

[Claims] An inner surface of a front glass of a cathode ray tube on which a dot or stripe black matrix is formed in advance,
A method for manufacturing a cathode ray tube, comprising a step of applying a phosphor slurry, exposing and developing to form a phosphor of each color between the black matrices, comprising a plurality of small holes, and discharging the phosphor slurry from the small holes. When the coating liquid discharge section is swept in one direction by one-way operation or reciprocating operation to form a phosphor coating film on the inner surface of the front glass, a part of the phosphor slurry supplied to the inside of the coating liquid discharge section A discharge step of continuously discharging the coating liquid to the outside of the coating liquid discharge section through an air vent passage, a stop operation of temporarily stopping the discharge of the phosphor slurry from the small holes of the coating liquid discharge section, and after the stop. Repeating a discharge resuming operation for resuming the discharge of the phosphor slurry from the small holes of the application liquid discharging section. When performing the discharge resuming operation after the stop operation, bubbles generated in the phosphor slurry in the phosphor slurry supply pipe line, together with a part of the phosphor slurry, are passed through the air vent passage to the outside of the coating liquid discharge section. A method for manufacturing a cathode ray tube, wherein the discharge step of continuously discharging to a cathode ray tube is performed. 2. The phosphor slurry discharged from the air vent passage when the phosphor coating film is applied to the inner surface of the front glass by sweeping the coating liquid discharge section in one direction by one-way operation or reciprocating operation. The discharge amount per unit time of the blue phosphor slurry or the green phosphor slurry is 3 times the discharge amount per unit time of the blue phosphor slurry or the green phosphor slurry discharged from the whole of the plurality of small holes of the coating liquid discharge section. The method for producing a cathode ray tube according to claim 1, wherein the content is 10% to 10%. 3. A unit time of the red phosphor slurry discharged from the air vent passage when applying the phosphor slurry film on the inner surface of the front glass by sweeping the coating liquid discharge unit in one direction by one-way operation or reciprocating operation. 2. The discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes per unit time is 5 to 12%.
Or the method for manufacturing a cathode ray tube according to 2. 4. The method according to claim 1, wherein in the repetition step, the discharge of the phosphor slurry from the coating liquid discharge unit is temporarily stopped when the coating liquid discharge unit passes above the outer peripheral wall of the front glass. Item 4. The method for producing a cathode ray tube according to any one of Items 1 to 3. 5. A coating liquid discharging section having a plurality of small holes and discharging a coating liquid from the small holes is swept in one direction by one-way operation or reciprocating operation to apply the coating liquid to an object to be coated. In the liquid coating method for forming a film, when the coating liquid discharge section is swept in one direction by one-way operation or reciprocating operation to form a coating film on the application target, the coating liquid discharge section is supplied to the inside of the coating liquid discharge section. A step of continuously discharging a part of the coating liquid to the outside of the coating liquid discharge unit through the air vent passage, and a stop operation of temporarily stopping the discharge of the coating liquid from the small hole of the coating liquid discharge unit, A repetition step of repeating a discharge resuming operation for resuming the application liquid discharge. When the discharge resumption operation is performed after the stop operation in the repetition step, the discharge liquid is generated in the coating liquid in the coating liquid supply pipe path. The liquid applying method, wherein the discharging step is performed to continuously discharge the generated bubbles together with a part of the coating liquid to the outside of the coating liquid discharge section through the air vent passage. 6. An inner surface of a front glass of a cathode ray tube in which a dot or stripe black matrix is formed in advance,
In a cathode ray tube manufacturing apparatus having a process of applying a phosphor slurry, exposing and developing to form a phosphor of each color between the black matrices, a coating having a plurality of small holes and discharging the phosphor slurry from the small holes. When forming a phosphor coating film on the inner surface of the front glass by sweeping the liquid discharge unit in one direction by one-way operation or reciprocating operation, a part of the phosphor slurry supplied to the inside of the coating liquid discharge unit is removed. A discharge mechanism for continuously discharging the coating liquid discharge unit to the outside through the air vent passage; a stop operation for temporarily stopping discharge of the phosphor slurry from the small holes of the coating liquid discharge unit; A control unit for repeatedly performing a discharge restart operation for restarting discharge of the phosphor slurry from the small holes of the coating liquid discharge unit; When performing the discharge resuming operation after the operation, the discharge mechanism causes bubbles generated in the phosphor slurry in the phosphor slurry supply pipe line, together with a part of the phosphor slurry, to pass through the air vent passage and the coating solution. An apparatus for manufacturing a cathode ray tube, wherein the cathode ray tube is continuously discharged to the outside of the discharge section. 7. When the control unit causes the coating liquid discharge unit to sweep in one direction by one-way operation or reciprocating operation to apply the phosphor coating film to the inner surface of the front glass, the discharge mechanism includes the air vent passage. The amount of blue phosphor slurry or green phosphor slurry discharged from the phosphor slurry per unit time per unit time is the blue phosphor slurry or green phosphor discharged from the plurality of small holes of the application liquid discharge unit. Slurry discharge per unit time 3 ~
The cathode ray tube manufacturing apparatus according to claim 6, wherein the control is performed so as to be 10%. 8. When applying the phosphor slurry film on the inner surface of the front glass by sweeping the coating liquid discharge unit in one direction by one-way operation or reciprocating operation by the control unit, the discharge mechanism is configured to perform a discharge from the air vent passage. 8. The method according to claim 6, wherein the discharge amount of the red phosphor slurry discharged per unit time is controlled to be 5 to 12% of the discharge amount per unit time of the red phosphor slurry discharged from the plurality of small holes. A cathode ray tube manufacturing apparatus as described in the above. 9. The control section temporarily stops the discharge of the phosphor slurry from the coating liquid discharge section when the coating liquid discharge section passes above the outer peripheral wall of the front glass. The cathode ray tube manufacturing apparatus according to any one of claims 6 to 8, wherein the apparatus is controlled to: