JP2003203568A - Cleaning treatment method and cleaning treatment device of face panel for color cathode-ray tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning treatment device capable of surely performing cleaning treatment by adding respective optimal cleaning conditions of a new face panel and a regenerating face panel. <P>SOLUTION: A cleaning solution for cleaning an inside surface of the regenerating face panel is composed of a solution including a tannic acid of at least 10% to a 1 to 5% solution of acid ammonium fluoride. A face panel inside surface cleaned by this solution is cleaned by spray. A first cleaning device 16, a first water washing device 17, a second cleaning device 18, and a second water washing device 19 are arranged in order along a carrying device 15 for mixedly carrying the new face panel 35 and the regenerating face panel 37. Cleaning is performed by using the cleaning solution in the first cleaning device 16. Cleaning is performed by using a fluoric acid in the second cleaning device 18. High pressure spray water washing is performed by using pure water in the first and second water washing devices 17 and 19. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a face panel for a color cathode ray tube, and in particular, a newly manufactured new face panel and a defective product at the stage of forming a black light absorption layer, which is cleaned. A method for cleaning a face panel for a color cathode ray tube, in which a good face panel can be obtained by cleaning the inner face of each face panel and the face face for reproduction for reuse after cleaning. And a cleaning apparatus.

[0002]

2. Description of the Related Art Generally, a color cathode ray tube has a face panel 61 and a face panel 61 as shown in FIG.
Has a funnel-shaped funnel 62 joined to the inner surface of the face panel 61, and a phosphor screen 63 including a three-color phosphor layer and a black light absorbing layer is provided on the inner surface of the face panel 61. A shadow mask 65 attached to a mask frame 64 is arranged inside the face panel 61 facing the screen 63, and an inner shield 66 extending in the funnel 62 direction is also attached to the mask frame 64. Has been done. This phosphor screen 63 is a black matrix type in which a dot-shaped or striped three-color phosphor layer that emits blue, green, and red, and a black light absorption layer is provided in the gap between the three-color phosphor layers, or It is formed as a phosphor screen 63 called a black stripe shape.

On the other hand, the funnel 62 has a cylindrical neck 6
An electron gun 69 that emits three electron beams 68B, 68G, and 68R is arranged in the inside 7. The three electron beams 68B, 68G, 68 emitted from the electron gun 69
R is a deflection yoke 7 mounted on the outside of the funnel 62
The color image is reproduced and displayed on the phosphor screen 63 by deflecting by 0, selecting by the shadow mask 65, and horizontally and vertically scanning the phosphor screen 63.

The phosphor screen 63 of such a color cathode ray tube is manufactured through the following manufacturing process.

That is, a newly created face panel 6
1 or a defective product at the stage of forming the black light absorption layer, and the inner surface of the face panel 61 is washed to remove the black light absorption layer and is used again for forming the phosphor screen 63. Then, the inner surface of each face panel 61 is degreased and washed. A photosensitive film is formed by applying a photosensitizer to the inner surface of the degreased and washed face panel 61,
This photosensitive film is exposed through the shadow mask 65 and developed to form a resist having a matrix or stripe pattern at the phosphor layer forming position. Next, black paint is applied to the inner surface of the face panel 61 on which the resist is formed to form a black paint layer. Next, the black paint layer on this resist is peeled off together with the resist to form a matrix- or stripe-shaped black light absorbing layer.

What is determined to be a defective product at this stage is rotated as the reproduction face panel 61.

After that, a phosphor slurry containing a phosphor and a photosensitizer as a main component is applied to the gap between the black light absorption layers to form a phosphor slurry layer, and the phosphor slurry layer is passed through a shadow mask 65. It is exposed and developed into a phosphor layer, which is 3
The phosphor screen 63 is formed by repeating the color phosphor layer.

In order to clean the inner surface of the face panel 61 prior to the formation of the black light absorbing layer, as shown in FIG. 7, various cleaning and washing processes are performed. In FIG. 7, the left side of the drawing shows a state in which the cleaning solution and the washing water are sprayed from the nozzles to the inner surface of the face panel 61, and the right side of the drawing shows the solution and the like.

First, in the first position ((a) in the figure), the inner surface of the face panel 61 faces downward and faces the cleaning nozzle 71.
% Of hydrofluoric acid is sprayed to apply to the inner surface of the face panel 61 for cleaning. Next, the face panel 61 is, for example, 10
It is intermittently moved to the second position ((b) in the figure) every second. In this second position, water for washing is jetted from the nozzle 72 toward the inner surface of the face panel 61,
The remaining black light absorbing layer and the cleaning solution are washed away. After that, it is moved to the third position ((c) in the figure), and again, 15% hydrofluoric acid is sprayed from the nozzle 73 to apply and wash, and then in the fourth position ((d) in the figure). The inner surface of the face panel 61 is washed by jetting water for washing from the nozzle 74 to wash out hydrofluoric acid.

The hydrofluoric acid used in this cleaning treatment has a high cleaning ability for the glass surface even at a low concentration, but when cleaning the black light absorbing layer, the portion where the black light absorbing layer is not formed, that is, the phosphor is used. From the non-black light absorbing layer portion where the glass surface on which the layer is to be formed is exposed, it enters the interface between the black light absorbing layer and the glass surface, and undergoes the process of rooting the black light absorbing layer. In order to clean the inner surface of the face panel 61 within the limited index time (8 to 30 seconds) during the process, it is necessary to use a high concentration of hydrofluoric acid.

When an acidic ammonium fluoride solution is used as a cleaning solution, it is possible for this solution to permeate the black light absorbing layer and directly act on it. Is not very expensive. For this reason, there is a possibility that defects may occur due to insufficient cleaning of the glass surface. Particularly in the case of the reproduction face panel 61 with the black light absorbing layer attached, film residue of the black light absorbing layer occurs,
Further, if the black light absorbing layer remains on the inner surface of the face panel 61 for too long, the etching of the inner surface of the glass by the cleaning solution progresses unevenly, and as a result, the unevenness of the inner surface of the face panel 61 becomes severe and the inner surface glares. (Inner burn) is a problem.

[0012]

As described above, reduction of harmful substances such as fluorides has become an urgent task, especially in recent years, from the viewpoint of environmental consideration. It is necessary to process it in a direction that avoids its use. However, in the cleaning treatment with hydrofluoric acid, it is necessary to use a high concentration of hydrofluoric acid. For this reason, the cleaning step with the cleaning solution is dispersed in two, and 15% concentration of hydrofluoric acid is used in each step. It is devised so that it will be processed.

That is, in both the new face panel 61 and the reproduction face panel 61, the inner surface of the face panel 61 is washed with hydrofluoric acid having a concentration of 15% at the first position,
In the case of the new face panel 61, the water washing process is performed at the next second position, but in the case of the reproduction face panel 61, the water washing process is not performed and the face face is held at that position. Next, in the third position, the inner surface of the face panel 61 is washed again with 15% concentrated hydrofluoric acid, and in the last fourth position, it is washed with water to obtain a clean inner surface of the face panel 61.

However, even if such cleaning treatment is carried out, defects due to insufficient cleaning of the glass occur, and in the case of a reproduction face panel with a black light absorbing layer, there is a film residue of the black light absorbing layer or internal burning etc. There was a problem.

The present invention has been made in order to solve such a problem, and ensures the cleaning process by adding optimum cleaning conditions to each of the new face panel and the reproduction face panel. It is an object of the present invention to provide a method and apparatus for cleaning a face panel for a color cathode ray tube capable of performing the above.

[0016]

According to the present invention, there is provided a method for cleaning a face panel for a color cathode ray tube for cleaning the inner surface of a face panel through a cleaning device and a water cleaning device, wherein ammonium acid fluoride is used as a cleaning solution in the cleaning device. Cleaning was performed using a cleaning solution containing at least 10% tannic acid with respect to a 1 to 5% solution, and the inner surface of the cleaned face panel was spray-cleaned in a water cleaning device.

Further, a carrying device for carrying out intermittently at a predetermined time interval with the inner surface of the face panel facing downward, and a first cleaning device and a first cleaning device, which are sequentially arranged side by side on the opposite side in the traveling direction of the carrying device. 1 washing device, 2nd washing device and 2nd washing device are provided, the 1st washing device has the solution tank which stores the acidic ammonium fluoride solution and the nozzle which injects this solution to the inside of the face panel, Each of the first and second water washing devices has a water tank containing pure water and a nozzle for injecting the pure water at high pressure toward the inner surface of the face panel,
The second cleaning device has a solution tank containing a hydrofluoric acid solution and a nozzle for injecting this solution toward the inner surface of the face panel, and each of these devices is provided with a device for selectively cleaning the inner surface of the face panel. Configured.

According to such a cleaning method and cleaning apparatus, the inner surface of the face panel can be reliably cleaned not only when a new face panel is used but also when a reproduction face panel is mixedly applied. It is possible to obtain a face panel for a color cathode-ray tube that does not cause the occurrence of heat generation, internal burning, or the like, and it is also possible to configure these as an automated line.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method and apparatus for cleaning a face panel for a cathode ray tube according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an outline of a cleaning apparatus used for cleaning a face panel for a color cathode ray tube according to the present invention.

That is, the rubber rollers 11 made of a large number of chemical resistant materials are arranged at a predetermined interval so as to form a line in the traveling direction. The rubber roller 11 has a gear (not shown) at one end, and the gear is meshed with the endless chain 12. A drive gear 13 is meshed with the chain 12, and a rotational force is applied to the chain 12 by rotating the gear 13 by a motor 14 so that the rubber roller 11 is rotated to form a conveying device 15.

Below the carrier device 15, the carrier device 1 is provided.
The first cleaning device 16, the first water cleaning device 17, the second cleaning device 18, and the second water cleaning device 19 are sequentially arranged at predetermined intervals in correspondence with the traveling direction of No. 5.

The first cleaning device 16 is provided with a first cleaning solution tank 20, and a spray nozzle 22 is attached to the solution tank 20 via a valve 21. The nozzle 22 is located between the rubber rollers 11. It is located in the gap.
Similarly, the first washing device 17 is also provided with a first washing water tank 23, a spray nozzle 25 is attached via a valve 24, and the spray nozzle 25 is arranged so as to face the gap portion of the rubber roller 11. Similarly, in the second cleaning device 18, the second cleaning solution tank 2
6, a valve 27 and a spray nozzle 28 are provided.
Similarly, the second washing device 19 is also provided with a second washing water tank 29, a valve 30, and a spray nozzle 31, and these nozzles 28 and 31 similarly face the gap portion of the rubber roller 11. It is arranged to.

On the other hand, on the receiving side of the carrying device 15, a photodiode 32 and a photosensor 33 are arranged in a gap portion of the rubber roller 11 at positions facing each other with the rubber roller 11 interposed therebetween. Is connected so as to be supplied to a control circuit 34 such as a microcomputer, and this control circuit 34 also connects each valve 2
1, 24, 27, 30 and the motor 14 are also connected to control each of them.

In the cleaning apparatus thus constructed, the motor 14 is driven to rotate intermittently by the control circuit 34, and the chain 12 is driven accordingly to rotate each rubber roller 11 intermittently. A new face panel 35 whose inner surface is to be cleaned and a black matrix or black stripe type black light absorbing layer on the rubber roller 11 are determined to be defective when the black light absorbing layer is formed, and the inner surface needs to be cleaned again. In a state where the reproduction face panel 37 in which 36 is attached to the inner surface is mixedly mounted, the face panels 35 and 37 are sequentially placed in the same direction with the inner surfaces facing downward so as to face the rubber roller 11 side. Of course, the new face panel 35 alone, the reproduction face panel 37 alone, or a predetermined number of them may be grouped together and mixedly mounted.

The new face panel 35 or the reproduction face panel 37 placed on the carrying device 15 is
The light emitted from the photodiode 32 is detected by the photo sensor 3
By a light sensing device 38 configured to receive at
It is determined whether it is a new product or a face panel 35, 37 for reproduction. For example, in the case of a new face panel 35, the light of the photodiode 32 is directly input to the photo sensor 33 because the face panel 35 is transparent, and the output of the photo sensor 33 is transmitted to the control circuit 34, so that the target product is It is determined to be a new face panel 35. On the contrary, in the case of the reproduction face panel 37, the face panel 37
Since the black light absorbing layer 36 is present on the inner surface of the photo diode 32, the light of the photodiode 32 is blocked by the black light absorbing layer 36 and does not reach the photo sensor 33 side, or a predetermined amount of transmitted light is not generated. Then, the control circuit 34 determines that the target product is the reproduction face panel 37. In this way, with the new face panel 35 and the reproduction face panel 37 mounted on the transport device 15, the type of the target product is automatically determined before the cleaning process.

The face panels 35 and 3 thus determined
7 is intermittently driven and conveyed to each processing position by the conveying device 15, for example, at intervals of 10 seconds. This intermittent driving time setting is set by the control circuit 34, and can be performed by controlling the power supply of the motor 14 by the control circuit 34. In this way, when the object arrives at the first cleaning device 16 which is the first position and the target product is the new face panel 35 which is determined to be the new face panel 35 by the output of the light detection device 38, a predetermined stop is performed. Although it is stopped at the position for 10 seconds, which is time, the valve 21 of the first cleaning device 16 is closed by the control circuit 34, and the cleaning process is not performed. Similarly, even when the new face panel 35 reaches the first second washing device 17 which is the next second position, the valve 24 is closed by the control circuit 34 and the washing process is not performed.

On the other hand, when the object is judged to be the reproduction face panel 37 by the light detection device 38, when the object is conveyed to the position of the first cleaning device 16 and stopped, the first cleaning device 1
The valve 21 of No. 6 is opened by the control circuit 34, the first cleaning solution is sprayed from the nozzle 22, and the cleaning solution is applied to the inner surface of the reproduction face panel 37 for cleaning. Then 1
When 0 seconds has elapsed, the transport device 15 starts driving, transports the reproduction face panel 37 to the position of the first water washing device 17 at the second position, and stops. In this position, the valve 24 is opened by the control circuit 34, and the first flush water tank 2
3, washing water is sprayed from the nozzle 25 to wash the inner surface of the face panel 37. The first cleaning device 16 and the first water cleaning device 17 in the first and second positions stop the operation with respect to the new face panel 35, and operate only when the reproduction face panel 37 arrives. Is controlled by the control circuit 34.

On the other hand, in the second cleaning device 18 in the third position, any face panel 35, 37 operates, and at the stage of reaching this position, the valve 27 is activated based on the instruction of the control circuit 34. When opened, the cleaning solution in the second cleaning solution tank 26 is sprayed from the nozzle 28, and the cleaning solution is applied to the inner surface of each face panel 35, 37 for cleaning. After this cleaning is completed, the face panels 35 and 37 are transported to the fourth position by the transport device 15, and the valve 3 is similarly driven based on the instruction of the control circuit 34.
0 is opened, and the wash water from the wash water tank 29 is discharged to the nozzle 3
The inner surface of the face panels 35, 37 is washed with water so as to wash away the cleaning solution that has been sprayed through 1 and has been used for the cleaning in the previous stage, and the cleaning treatment of the inner surfaces of the face panels 35, 37 is completed.

If necessary, the fifth position is set after the fourth position, and dry air is jetted to the inner surfaces of the face panels 35, 37, so that the face panels 35, 37
It is also possible to arrange a drying device (not shown) for drying the inner surface of 37.

The valves 21, 24, 27, 30 are synchronized with the drive of the motor 14 and the control circuit 34, and the motor 14 is stopped and the conveying device 15 is stopped for a predetermined period. The valves 21, 24, 27, 30 are controlled so as to be selectively opened, and the light detection device 38 is placed on the carrier device 15 on the face panels 35, 37.
If it is also detected whether or not the face panel 35 or 37 is placed, or if it is configured by another detection means, the transport device 1 in which the face panels 35 and 37 are not placed according to the detection output.
Since it is possible to specify the location on 5, the valves 21, 24, 27, 30 of the corresponding devices 16, 17, 18, 19 which are synchronously driven are closed only during the non-mounting period. It is possible to stop the injection of the unnecessary solution or the washing water, and it is possible to prevent unnecessary troubles such as wasteful injection of the cleaning solution or the washing water. Further, the control of the injection from the nozzles 22, 25, 28, 31 is performed by each tank 2 arranged in each device 16, 17, 18, 19.
It may be configured to control the pressurizer (not shown) side added to 0, 23, 26, 29.

The first and second cleaning devices 1 configured as described above and arranged at each position of the cleaning device for performing each processing.
6, 18, the first and second water washing devices 17, 19,
Further, a detailed description will be given with reference to FIG.

That is, in FIG. 2, the nozzles 22, 25, 28, and
31 shows the state where the cleaning solution and the washing water are sprayed from 31
The solution and the like are shown on the right side of the figure.

First, in the first cleaning device 16 ((a) in the figure) in the first position, acid fluorination is performed to clean the black light absorption layer 36 remaining on the inner surface of the reproduction face panel 37. The ammonium solution is applied to the inner surface of the reproduction face panel 37 by the nozzle 22 and washed. At this time, the ammonium oxide fluoride solution may be used as it is, but in order to wash it within a predetermined processing time (for example, 8 to 30 seconds), it is necessary to set the solution concentration to 5% or more. However, if tannic acid with a concentration of 0.1-0.5% is added in an amount of 10% or more with respect to the total amount of ammonium acid fluoride, the concentration of the ammonium acid fluoride solution can be reduced to 1-5%. Moreover, it becomes possible to perform cleaning without lowering the cleaning effect. This is because tannic acid roughens the surface of the black light absorption layer and the acidic ammonium fluoride solution easily penetrates into the black light absorption layer, so that the concentration of tannic acid mixed should be 10% of that of ammonium oxide fluoride. It was found that the effect was most effective when set, and that the effect was not particularly changed even if added more.

Next, the coating solution of the acidic ammonium fluoride solution is peeled off and dissolved, and the black light absorbing layer and the cleaning solution remaining on the inner surface of the face panel 37 are washed with the first water-washing device 17 (see FIG. Wash with water in b)). In the water washing device 17, pure water is sprayed from the flat nozzle 25 for spraying toward the inner surface of the face panel 37 at a flow rate of 4 L / min or more and at a pressure of 0.7 MPa or more, and the inner surface of the face panel 37 is washed under high pressure.

Here, the cleaning pressure was changed and the correlation between the concentration of acidic ammonium fluoride and tannic acid and the cleaning power of the face panel was confirmed by experiments.

That is, FIGS. 3 to 5 show the cleaning degree when the tannic acid concentration (%) was changed with respect to 1%, 3% and 5% ammonium acid fluoride solutions, respectively. FIG. 4 shows the case of washing with water at a flow rate of 1 L / min and a pressure of 0.2 MPa and a flow rate of 2.7 L / min and 0.5.
FIG. 5 shows the degree of cleansing when washed with water at a pressure of MPa and at a flow rate of 4 L / min and at a pressure of 0.7 MPa.

The degree of cleaning at this time is determined by the following five-level evaluation of the cleaning condition when the face panel with the black light absorbing layer is washed with water. The time for applying and washing the ammonium chloride solution to the inner surface of the face panel and the time for rinsing pure water in the first rinsing device 17 are set to 7 seconds, respectively.

Degree of cleansing 1: No drop 2: Almost no drop 3: Partially left 4: Nearly complete drop (defective rate of 0.05% or more) 5: Complete drop (defective rate less than 0.05%) In this cleaning degree rank, the areas corresponding to ranks 4 and 5 are the areas that can be reused in the reproduction face panel 37.

As is apparent from FIGS. 3 to 5,
In order to obtain a rank 4 or higher, which is sufficiently washed, the tannic acid concentration is 0.3% or higher and the acidic ammonium fluoride solution having a concentration of 3% or 5% is used in any case. It can be seen that it is sufficient to add each with each cleaning pressure. In order to achieve the highest rank of 5 among these, the flow rate is 4
It was found that setting the cleaning pressure to 0.7 MPa at L / min was most effective.

Therefore, the first water washing device 17 is set under the condition that the pressure is 0.7 MPa or more at a flow rate of 4 L / min or more, which enables the most effective water washing. Moreover, in this washing with water, deionized water called pure water is used to suppress the occurrence of glass defects. When city water or industrial water is used as this washing water, alkaline earth metals such as calcium ions contained in the city water or industrial water are used as a cleaning solution during the cleaning process in the next second cleaning device 18. Alkaline earth metal fluorides may be formed by reacting with hydrofluoric acid, which may adhere to the inner surface of the face panel 37 and cause glass defects. To prevent this, pure water is used and high-pressure cleaning is performed. By applying, it is possible to wash away the remaining black light absorption layer,
The film defects of the black light absorbing layer due to the residual black light absorbing layer do not occur.

Then, in the second cleaning device 18 (FIG. 7 (c)) at the third position, hydrofluoric acid having a concentration of 10% is sprayed from the nozzle 28 to the inner surfaces of the face panels 35, 37 to inject the inner surfaces of the face panels 35, 37. To wash. In this cleaning step, since the cleaning is to finish the inner surfaces of the face panels 35 and 37, it is not necessary to increase the concentration of hydrofluoric acid used for cleaning, and the concentration of hydrofluoric acid of 3% to 10% is used. To do. It is sufficient that the concentration of hydrofluoric acid is around 5%, and even if high concentration of hydrofluoric acid of 10% or more is used,
Although there is not much difference in the cleaning ability, on the contrary, there is a possibility that the concentration becomes too high and the inner surfaces of the face panels 35 and 37 may be burnt or scratched.

After this cleaning is completed, in the second water washing device ((d) in the figure) at the fourth position, the nozzle 3
Pure water having a flow rate of 1 to 4 L / min and a pressure of 0.7 MPa is sprayed onto the inner surfaces of the face panels 35 and 37, and the foreign substances on the inner surfaces of the face panels 35 and 37 in the hydrofluoric acid cleaning react with hydrofluoric acid to generate. The residual substances such as silica fluoride are washed away, and a series of cleaning treatment is completed. After that, the face panels 35 and 37 after the cleaning process are dried,
It is used for making a phosphor screen.

Here, a comparison is made between a product in which a black light absorbing layer is formed on a face panel cleaned by the cleaning method according to the present invention and a comparative product in which the black light absorbing layer is formed by changing these processing conditions. Then, the effect was confirmed.

Implemented product 1 A first cleaning device, which is the first processing position, using a cleaning processing device that moves the face panel every 10 seconds and performs cleaning processing during the period in which the face panel is stopped at each position. 16, the inner surface of the face panel is coated with a 5% solution of ammonium acid fluoride containing 0.5% of tannic acid for cleaning, and the first water cleaning apparatus 1 is in the second processing position.
7, pure water with a flow rate of 4 L / min is 0.7 MPa
Sprayed at pressure of 2nd and 3rd processing position
In the cleaning device 18, 10% concentration of hydrofluoric acid is applied for cleaning, and in the second water cleaning device 19 in the fourth position, pure water having a flow rate of 4 L / min is sprayed at a pressure of 0.7 MPa. After finishing the cleaning process of the inner surface of the face panel, a black light absorbing layer was formed on the inner surface of the face panel.

Product 2 A cleaning device which moves the face panel every 10 seconds and performs cleaning treatment during the stop period of the face panel at each position is used as a first cleaning device in the first processing position. 16, the inner surface of the face panel is coated with a 1% solution of ammonium acid fluoride containing 0.1% of tannic acid for cleaning, and the first water washing apparatus 1 is in the second processing position.
7, pure water with a flow rate of 4 L / min is 0.7 MPa
Sprayed at pressure of 2nd and 3rd processing position
In the cleaning device 18, 3% concentration of hydrofluoric acid is applied for cleaning, and in the second water cleaning device 19 in the fourth position, pure water with a flow rate of 4 L / min is sprayed at a pressure of 0.7 MPa. After finishing the cleaning process of the inner surface of the face panel, a black light absorbing layer was formed on the inner surface of the face panel.

Comparative Product 1 A first cleaning device which is a first processing position, which uses a cleaning processing device that moves the face panel every 10 seconds and performs cleaning processing during the face panel stop period at each position. 16, the inner surface of the face panel is coated with a 5% solution of ammonium acid fluoride containing 0.5% of tannic acid for cleaning, and the first water cleaning apparatus 1 is in the second processing position.
7, 0.7 M of industrial water with a flow rate of 4 L / min
Spraying is performed at a pressure of Pa, 10% hydrofluoric acid is applied and cleaned in the second cleaning device 18 in the third processing position, and the flow rate is 4 L / min in the second water cleaning device 19 in the fourth position. After the cleaning treatment of the inner surface of the face panel was completed by spraying pure water of above at a pressure of 0.7 MPa, a black light absorbing layer was formed on the inner surface of the face panel.

Comparative product 2 The first cleaning device, which is the first processing position, uses the cleaning processing device that moves the face panel every 10 seconds and performs the cleaning process during the stop period of the face panel at each position. In FIG. 16, 15% hydrofluoric acid is applied to the inner surface of the face panel for cleaning, held by the first water cleaning device 17 in the second processing position, and held in the second cleaning device 18 in the third processing position. % Hydrofluoric acid is applied and washed, and in the second water washing device 19 at the fourth position, 0.7% pure water with a flow rate of 4 L / min is used.
After spraying at a pressure of MPa to complete the cleaning treatment of the inner surface of the face panel, a black light absorbing layer was formed on the inner surface of the face panel.

Comparative product 3 A first cleaning device, which is the first processing position, using a cleaning processing device that moves the face panel every 10 seconds and performs cleaning processing during the face panel stop period at each position. 16, the inner surface of the face panel is coated with a 1% solution of ammonium acid fluoride containing 0.1% of tannic acid for cleaning, and the first water washing apparatus 1 is in the second processing position.
7, pure water with a flow rate of 1 L / min is 0.2 MPa
Sprayed at pressure of 2nd and 3rd processing position
In the cleaning device 18, 10% concentration of hydrofluoric acid is applied for cleaning, and in the second water cleaning device 19 in the fourth position, pure water having a flow rate of 4 L / min is sprayed at a pressure of 0.7 MPa. After finishing the cleaning process of the inner surface of the face panel, a black light absorbing layer was formed on the inner surface of the face panel.

Comparative product 4 The first cleaning device, which is the first processing position, uses the cleaning processing device that moves the face panel every 10 seconds and performs the cleaning process during the period in which the face panel is stopped at each position. In FIG. 16, a 5% solution of ammonium acid fluoride containing 5% of ammonium acid fluoride is applied to the inner surface of the face panel for cleaning, and in the first water washing device 17 in the second processing position, the flow rate is 4 L / min. Water 0.7
Spraying at a pressure of MPa, in the second cleaning device 18 in the third processing position, 10% concentration of hydrofluoric acid is applied and cleaned, and the second water cleaning device 19 in the fourth position.
In the above, after the cleaning treatment of the inner surface of the face panel was completed by spraying pure water with a flow rate of 4 L / min at a pressure of 0.7 MPa, a black light absorbing layer was formed on the inner surface of the face panel.

These practical products 1 and 2 and comparative products 1 to 4
In the above, 1000 new face panels and 500 face panels for reproduction were prepared, washed by each method, and a black light absorbing layer was formed on the inner surface of each face panel after the washing treatment. The occurrence rate of the film defect of the black light absorption layer of No. 1 and the occurrence rate of those which were judged to be defective due to severe internal glare were investigated. The results of the investigation are shown in Table 1.

[Table 1] As can be seen from Table 1, in the case of the practical product 1, neither the film defect due to the black light absorbing layer nor the internal surface glare was observed in the new face panel. Even in the case of a reproduction face panel, the film defect of the black light absorption layer is only 0.
Although it was found to be 02%, it was suppressed to a state where there was almost no problem, and no internal glare was found. Further, in the case of the implementation product 2, both the new face panel and the reproduction face panel are 0.03% and 0.06%.
% And some film defects due to the black light absorption layer were found,
There is almost no problematic quantity, and no internal glare has occurred.

On the other hand, in Comparative Products 1 to 4,
Both the new face panel and the reproduction face panel have a film defect due to the black light absorption layer, and even if the film defect is relatively small, the inner surface is glaring and the cleaning process is sufficient. It is hard to say that it is done. In particular, in the case of the reproduction face panel of Comparative product 3, the black light absorption layer formed in the previous stage which became defective was not sufficiently removed by washing, and the majority thereof remained. Was there.

As described above, the cleaning treatment method by the cleaning treatment apparatus according to the present invention was used to perform cleaning treatment on a new face panel and a recycled face panel. Is low, and you can see how efficiently and surely it is cleaned. Moreover, these cleaning processing devices can be assembled as an automated line, which is suitable for labor saving.

The present invention is not limited to the above-described embodiments, and for example, the conveying means for moving the face panel is not limited to chain drive, but may be gear drive or belt drive. It goes without saying that the detection device can be configured by a device other than the photodiode or the photosensor, and can be applied or modified in various other ways.

[0055]

As described above, according to the present invention,
By setting the cleaning solution used in the step of cleaning the black light absorption layer of the reproduction face panel and the step of cleaning the inner surface of the face panel to the most effective solution, it is possible to remove harmful substances of high concentration. It is possible not only to suppress the generation, but also to suppress the film defect of the black light absorbing layer due to the glare on the inner surface of the face panel and the insufficient cleaning,
It is also possible to automate these cleaning processing steps.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view for explaining a cleaning processing apparatus for a face panel for a color cathode ray tube according to the present invention.

FIG. 2 is an explanatory diagram for explaining a method of cleaning a face panel for a color cathode ray tube according to the present invention.

FIG. 3 is a measurement diagram showing the correlation between the amount of pressurized water and the cleaning degree during the water washing process used in the method for washing the face panel for a color cathode ray tube according to the present invention.

FIG. 4 is a measurement diagram showing the correlation with the degree of cleaning when the amount of pressurized water during the water washing process is changed.

FIG. 5 is a measurement diagram showing the correlation with the degree of cleaning when the amount of pressurized water during the water washing treatment is further changed.

FIG. 6 is a cross-sectional view showing the configuration of a conventional color cathode ray tube.

FIG. 7 is an explanatory diagram for explaining a conventional method for cleaning a face panel for a color cathode ray tube.

[Explanation of symbols]

15: Transport device 16: First cleaning device 17: First water washing device 18: Second cleaning device 19: Second water washing device 20: First cleaning solution tank 22: Valve 23: First flush water tank 25: Valve 26: Second cleaning solution tank 28: Valve 29: Second flush water tank 31: Valve 32: Photodiode 33: Photo sensor 35: New face panel 36: Black light absorbing layer 37: Playback face panel 38: Photodetector

Claims (7)

[Claims] 1. A method for cleaning a face panel for a color cathode ray tube, which comprises a cleaning process for cleaning the inner surface of a face panel through a cleaning device and a water cleaning device, wherein the cleaning solution used in the cleaning device is 1-5% ammonium acid fluoride solution. And a cleaning solution containing at least 10% tannic acid, and spray cleaning the inner surface of the cleaned face panel in a water cleaning device. 2. The cleaning device and the rinsing device respectively include first and second rinsing devices and first and second rinsing devices, and the rinsing and rinsing devices are alternately and selectively performed. In the first cleaning device, cleaning is performed using the cleaning solution, followed by high pressure spray water cleaning using pure water, and further cleaning with 3 to 10% hydrofluoric acid in the second cleaning device, and then pure water. The method for cleaning a face panel for a color cathode ray tube according to claim 1, wherein high-pressure spray washing with water is performed. 3. The high pressure spray washing with water is 4 L / min.
The method for cleaning a face panel for a color cathode ray tube according to claim 2, wherein the pure water having the above flow rate is applied at a pressure of 0.7 MPa or more. 4. A transfer device for intermittently transferring at a predetermined time interval with the inner surface of the face panel facing downward, and a first cleaning device sequentially arranged in parallel with the face panel side in the traveling direction of the transfer device. A first water washing device, a second water washing device, and a second water washing device are provided, and the first washing device has a solution tank containing an acidic ammonium fluoride solution and a nozzle for injecting the solution toward the inner surface of the face panel. The first and second washing devices each have a water tank for containing pure water and a nozzle for injecting the pure water at high pressure toward the inner surface of the face panel, and the second cleaning device contains a hydrofluoric acid solution. A face panel for a color cathode ray tube, which has a solution tank and a nozzle for ejecting this solution toward the inner surface of the face panel, and selectively cleans the inner surface of the face panel by each of these devices. Cleaning equipment. 5. The solution tank of the first cleaning device contains at least 10% of a 1-5% ammonium acid fluoride solution.
Containing a cleaning solution containing tannic acid, and a solution tank of the second cleaning device containing a hydrofluoric acid solution having a concentration of 3 to 10%,
Pure water having a flow rate of 4 L / min or more was discharged from the nozzle to 0.2
The cleaning apparatus for a face panel for a color cathode ray tube according to claim 4, wherein the spraying is performed at a pressure of 7 MPa or more. 6. The carrying device is provided with a photodetecting device for detecting the presence or absence of a black light absorbing layer on the inner surface of the conveyed face panel, and the first detecting device is provided according to the output of the photodetecting device.
The cleaning device for a face panel for a color cathode ray tube according to claim 4 or 5, wherein the cleaning device and the first water cleaning device are selectively operated. 7. A cleaning processing apparatus for a face panel for a color cathode ray tube according to claim 4, wherein a new face panel and a reproduction face panel are mixedly mounted on the transfer device. .