JPH0260026A - Formation of light absorbing film - Google Patents

Abstract

PURPOSE:To improve a production yield by automatically measuring the temperature of a panel thrown into a production process and controlling the applicable amount of a cleaning chemical and pure water at each cleaning position, depending upon the result of the measurement. CONSTITUTION:Each type of cleaning chemicals or pure water is classified into two constituting a cleaning chemical or pure water having a relatively high temperature and a cleaning chemical or pure water having a relatively low temperature for setting the temperature thereof in relation to characteristics and purposes. In the operation of a cleaning system, therefore, the cleaning amount of high and low temperature glass panels is made variable within an allowable range due to the application time and flowrate of the aforesaid chemical or pure water. A temperature difference between the aforesaid panels in a production line is thereby made small via the heat transfer of the aforesaid chemical and pure water, and finally a panel temperature is lowered to a level free from a problem at the time of exposure. According to the aforesaid construction, it becomes possible to reduce the irregularity of a product and improve a production yield.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method for forming a light absorption film on the fluorescent surface of a color picture tube.

[Conventional technology]

Currently, the fluorescent surface of color picture tubes is made of a so-called black matrix, which limits the light-emitting area of the phosphor with a light-absorbing material, such as a graphite film, and dramatically improves the contrast of the fluorescent surface. It's starting to change.

Next, a method for manufacturing a black matrix-formed fluorescent surface of a color picture tube will be explained.

First, the inner surface of the glass panel 1 forming the fluorescent surface shown in FIG. 2 is washed using ammonium fluoride of caustic soda and pure water and dried. Sometimes, a very thin layer of PVA is applied before drying.
A pre-coat film may be formed by spraying and drying a solution of Next, a resist film 2 is formed by applying a photoresist, for example, a resist solution containing polyvinyl alcohol and dichromate as main components, by a spin coating method.

Next, the resist film 2 is sufficiently dried and begins an exposure process. In the exposure process, a latent image is formed on the resist film 2 by an exposure device. That is, a shadow mask 3 as a color selection electric bridge is attached to a glass panel l, and one of the shadow masks 3 is illuminated by a mercury lamp 6 through a correction lens 4 and a light amount adjustment filter 5 for a certain period of time by opening and closing a shutter 7. A latent image is formed on the resist film 2 by sequentially exposing the light emitting positions of the resist film 2 to the openings.

Next, as shown in FIG. 3, resist dots or resist stripes 2a (hereinafter collectively referred to as "resist stripes"), which are a resist film pattern, are formed at the positions where the phosphor is to be applied by development. Form. Next, after drying the resist stripe 2a, a light-absorbing substance such as a graphite solution is applied by spraying or pouring onto the resist stripe 2a and dried to form a graphite film 9.
form.

Next, after sufficiently drying and heating the graphite film 9, an oxidizing agent, for example, 10% hydrogen peroxide solution, is injected into the inner surface of the glass panel l to act on the resist stripe 2a,
This is chemically decomposed.

The chemically decomposed resist stripe 2a and the graphite film 9 coated thereon are peeled off from the glass panel 1 in the next strong development process.

As a result, as shown in FIG. 4, the graphite film 9 remains at a position other than the position where the phosphor is attached and emits light, and the remaining graphite film 9 becomes a black stripe 9a as a light absorption film. Furthermore, the graphite film 9 in unnecessary areas adhered to the skirt portion of the glass panel 1 is removed and shaped by etching the glass surface with an aqueous solution of ammonium fluoride, and finally washed with water and dried to make it black. Complete matrix formation. Thereafter, in the same manner as in the formation of the resist stripes 2a, the steps of coating, exposing, and developing the phosphor slurries of the three primary colors, that is, green, blue, and red, are repeated to form the three primary colors, as shown in FIG. A phosphor surface is formed on which the primary color phosphor stripes 10 have been deposited.

Usually, a black matrix fluorescent surface is manufactured using a so-called automatic machine, in which a carrier to which the glass panel 1 is fixed is sequentially moved through a loop-shaped production line at a predetermined cycle time. . 6th
The cleaning process shown in the figure usually consists of about 10 positions, although it depends on the cycle time (hereinafter referred to as index) of the automatic machine. - For boat fishing, first degrease and remove organic components by alkaline cleaning 60 such as hot caustic soda to make subsequent acid cleaning more effective. Next, after rinsing 61 to wash away alkaline components, acid cleaning 62 with a component that dissolves glass, such as hydronic acid or acidic ammonium fluoride, is performed in 2 to 3 steps.
Next, circulating water cleaning 63 for removing acid components is performed, followed by pure water cleaning 64 for complete cleaning. After this, the process moves on to shaking off moisture using high-speed rotation, drying with a heater, and injecting resist.

[Problem to be solved by the invention]

When a light-absorbing film is formed through the manufacturing process described above, variations usually occur in the light-emitting area, that is, the stripe width. The causes of this variation include various variable factors such as fluctuations in the resist solution and changes in film pressure, variations in the width of the shadow mask slot during exposure, changes in the brightness of the light source, and the time from the end of exposure to development.

The inventor has studied and improved the degree of influence and control method for each of these variable items, and now the temperature fluctuation of the glass panel has become clear as an even larger variable factor. In other words, with recent automation of production lines, 8M
The feeding of panels into the line has also been automated, and panels that have gone through the heat treatment process at a fairly high temperature, relatively low temperature panels that were defective in the 8M process, and relatively high temperature panels that were defective in the phosphor coating (SC) process. This was due to an unavoidable situation in which panels such as panels with the lowest temperature, about room temperature, were thrown in as work-in-progress and were thrown in indiscriminately. According to confirmation, the variation in stripe width due to panel temperature fluctuations reaches 20 μm or more, and the variation within the standard is ±10
(exceeding .mu.m), which is extremely undesirable as it causes variations in yield and product quality in the manufacturing process. As a solution to this problem, the conventional method of manually introducing the materials has been able to select the materials based on the sense of warmth to the touch, but as explained earlier, this method cannot be adopted due to automation.

Therefore, it is essentially possible to automatically equalize the temperature of the input panel in advance. However, this method requires a considerable amount of equipment and is obviously problematic in terms of equipment and cost.

Therefore, this invention was made to solve the above-mentioned problems, and its purpose is to provide a method for forming a light-absorbing film that can be solved with a conventional line configuration and also can make the panel temperature almost uniform. do.

[Means to solve the problem]

In the light-absorbing film forming method according to the present invention, the application time of the chemical solution and cleaning water in the glass panel cleaning process is controlled by the temperature of the glass panel at the time of input, and the temperature of the chemical solution and cleaning water in the cleaning process is effectively utilized. However, the temperature of the glass panel which is in the low temperature range at the time of charging is increased, while the temperature of the glass panel which is in the high temperature range at the time of charging is lowered.

[Effect]

In this invention, various types of cleaning chemicals or cleaning pure water are used, depending on their characteristics and purpose, such as relatively high temperature cleaning chemicals or cleaning water, and relatively low temperature cleaning chemicals or cleaning water. Since the cleaning system is divided into two parts, it is possible to change the cleaning amount by varying the application time or flow rate of cleaning chemicals or purified water to high temperature panels and low temperature panels within the possible range. Or, the temperature difference between the input glass panels can be further reduced by heat transfer of the cleaning water.
Ultimately, it is possible to reduce the panel temperature difference during exposure to a level that does not cause any problems, thereby reducing product variations and improving manufacturing yield.

〔Example〕

Hereinafter, embodiments of the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a block diagram showing a cleaning step of a method for forming a light absorbing film according to a first embodiment of the present invention.

The points that differ from the conventional ones are a temperature measuring device 1) that measures the temperature of a non-contact panel using infrared rays before inputting the panel, a control device 12 that judges, stores, and controls the measurement results, and controls the amount of cleaning liquid applied to the panel ( An electromagnetic valve 13 for changing the time or flow rate) and a pressure regulating valve 14 are provided.

In the example of bookcase 1, the index time is 18 seconds (this includes 3 to 4 seconds of movement time, and the actual operating time is 13 to 14 seconds), and the settings for 10 cleaning positions are as shown in Table 1. As a result of comparing the internal temperature of the panel after resist application and drying, the conventional temperature was 43°C to 38°C, but it was 42°C to 40°C, and the variation was less than half that, which improved the quality in the manufacturing process. Yield has improved significantly.

Table 1 In the table, the display in seconds indicates the injection time of the chemical solution in kg/c
1! ! The unit display indicates the injection pressure of the chemical solution, and a high temperature panel indicates a temperature of 40°C or higher, and a low temperature panel indicates a pressure of less than 40°C.

Discharge team 1 The second embodiment of the present invention has the same structure as the first embodiment, except that the temperature of the acidic ammonium fluoride-based cleaning solution at cleaning position 6, which was conventionally kept at room temperature, was changed to 40°C. The settings are as shown in Table 2. Note that this temperature may be 35°C to 45°C.

Table 2 In this example, although temperature control for three positions, positions 6, 7, and 8, requires sensors and heaters (not shown), the conventional panel temperature difference is 43°C.
The difference between ~38°C and 42°C ~ 41°C could be almost eliminated, and the quality and yield in the manufacturing process were greatly improved.

In the above example, the temperature of the high-temperature side panel was 60°C, and the temperature of the low-temperature side panel was 20°C. Needless to say, there are various combinations depending on the line index and the configuration of the cleaning position, and the amount of cleaning liquid can be controlled depending on conditions such as time, pressure, and number of nozzles.

〔Effect of the invention〕

As explained above, according to the present invention, the temperature of the input panel is automatically measured, and the amount of cleaning chemical solution and pure water applied (action time) at each cleaning position can be controlled based on the result. Therefore, it is fully possible to add it to a conventional line, and it is possible to perform highly accurate dimensional control, which is highly effective in improving product quality and yield.

[Brief explanation of the drawing]

FIG. 1 is a block system diagram for explaining the light-absorbing film forming method according to the first embodiment of the present invention, and FIG. 2 is a main part for explaining the state in the exposure process during the manufacturing process of the fluorescent surface. The sectional views, FIGS. 3, 4, and 5 are sectional views of main parts to explain the manufacturing process of the fluorescent surface, and FIG. 6 is a block configuration diagram to explain the cleaning process of the glass panel. . 1)...Temperature measuring device, 12...Control device, 13.
... Solenoid valve, 1 ... Glass panel, 2 ... Resist film, 3 ... Shadow mask, 60 ... Alkali cleaning, 61 ... Rinse washing, 62 ... Acid cleaning, 63
...Circulating water cleaning, 64...Pure water cleaning. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] (1) After cleaning the inner or outer surface of the cathode ray tube glass panel with a chemical solution and pure water and drying it, apply a resist solution as a photosensitizer, dry it, and attach a shadow mask to limit the light-emitting areas of the three primary colors. A resist film pattern is formed by exposure and development, after which a light-absorbing film-forming solution is applied and dried, an oxidizing agent is applied to decompose the resist film, and then high-pressure development is performed to form a light-absorbing film pattern. In the light-absorbing film forming method for forming a film pattern, the temperature of the glass panel is measured before cleaning, and the cleaning with the chemical solution and pure water is performed using a chemical solution or a chemical solution set at a relatively high temperature for the high-temperature panel. The amount of cleaning water applied is relatively small, and the amount of chemical solution or cleaning water set at a relatively low temperature is set relatively large. A method for forming a light-absorbing film, characterized in that the applied amount is set to be relatively large, and the applied amount of the low-temperature chemical solution or cleaning water is set to be relatively small.