JPS61116731A - Manufacture of heat absorbing material thin film - Google Patents

Abstract

PURPOSE:To sharply improve workability while checking uneven atomizing by flushing a spray gun nozzle during suspension of intermittent operation followed by removing flushing water sticking to the nozzle by air. CONSTITUTION:After completely vacuum-evaporating a light reflecting metal thin film 4, water acryl emulsion 12 supplied from the head tank 11 with a spray gun 10 fixed to a reciprocator 9 while placing a glass face plate 1a is spray-applied. Water is emitted from a flushing nozzle 24 to the nozzle hole of the spray gun 10 stopped at a fixed position for performing flushing. Simultaneously, a washing brush 27 is operated. Next, air is jetted from the air nozzle 25 for removing drops and idle-blowing water acryl emulsion 12. Subsequently, the glass face plate 1a is moved to the graphite slurry spray position for spraying graphite slurry.

Description

Detailed Description of the Invention [Industrial Field of Application] This invention is a heat absorbing material thin film formed by spraying on a light reflective metal thin film deposited on the inner surface of a glass face plate of a color picture tube. The present invention relates to a method for producing an absorbent thin film.

[Conventional technology]

The fluorescent surface of a color picture tube emits light from a fluorescent film coated on the inner surface of the face plate that forms part of the tube body.
In order to effectively diffuse light toward the front of the color picture tube, that is, toward the viewer, a so-called metal bank structure, in which a light-reflecting metal thin film is deposited on a fluorescent film, is generally used.

This metal back fluorescent surface has the advantage of increasing the brightness of the color picture tube and preventing the phenomenon of ion burnout. FIG. 2 is a sectional view showing the configuration of the main parts of such a color picture tube, and this color picture tube has its envelope (1
A fluorescent film (2) is formed by applying a fluorescent film (2) to the inner surface of a face plate (Ja) that constitutes a part of the face plate (Ja). Although not shown in Figure 2, this fluorescence! ! ! An intermediate film (3) made of a film lacquer material containing an organic substance as a main component is formed on the surface of (2) to smooth the surface. A light-reflective metal thin film (4) made of aluminum is deposited on the surface of this intermediate @ (3) so as to cover it. A heat-absorbing material thin film (5) is formed on the surface of this light-reflective metal thin film (4).

Then, through the baking treatment, the binder of the fluorescent film (2) and the intermediate film (3) are removed by ashing.

Further, on the back side of the heat absorbing material thin film (5), a shadow mask (6) is provided at a predetermined distance from the heat absorbing material thin film (5).
) is arranged, and furthermore, an electron gun (7) is arranged on the neck (1b).
) are stored.

An electron gun (7
) The electron beam emitted from the shadow mask (6) hits the fluorescent film (2) corresponding to the minute holes provided in the shadow mask (6), and a color image is projected. In this case, the transmittance of the electron beam passing through the shadow mask (6) is as low as 15-80%, and the remaining 70-86% of the electron beam collides with the shadow mask (6) Iζ, and the collision energy becomes heat. This increases the temperature of the shadow mask (6).

As a result, the shadow mask (6) thermally expands and deforms.
The light emitting position of the fluorescent film (2) corresponding to the electron beam is shifted. This is called the doming phenomenon. The color shift that occurs along with this phenomenon is called mislanding, and when this mislanding occurs, the color image quality is significantly degraded.

Therefore, in order to reduce mislanding, a heat absorbing material thin film (5) is formed on the light reflective metal thin film (4), that is, on the electron gun (7) side.
) to absorb radiant heat and suppress thermal expansion. The heat absorbing material thin film (5) is generally formed by spraying graphite slurry. However, when spraying directly onto the light reflective metal thin film (4), the fluorescent film (2
) Graphite penetrates into the color picture tube, causing a problem that reduces the brightness of the color picture tube.

In order to solve this problem, a first paint, called a barrier film, made of, for example, an aqueous acrylic emulsion is similarly spray-coated onto the light-reflecting metal thin film (4) to form a barrier film, and a second paint is applied on top of the light-reflective metal thin film (4). Generally used is a method of spray coating a paint, that is, a graphite slurry, to form a heat-absorbing substance thin film (5). - Example 8
This will be explained with reference to the figures. Place the glass face plate (1a) on which the light-reflecting metal thin film (4) has been deposited on the holder (
The first paint (water-based acrylic emulsion) (6) is supplied from the head tank αη by one or more spray guns α1 mounted on the reciprocating machine (9) (8) and fixed to the reciprocating machine (9).
spray coat to form a barrier film. At this time, the spray gun QO moves as shown by the arrow in FIG. 4 using the reciprocating device (9) to spray the entire surface of the light reflective metal thin film (4). The glass face plate (1a) on which the barrier film has been formed is then transferred to a second paint spraying position. This state is shown in FIG. That is,
glass face spray) (la) Hamasking (2)
) is set above. This masking (to) is a fluorescent film (
2) Apply the second paint (Graphite Sura!J) to the other parts.
-) Prevention of Qf9 adhesion and heat-absorbing thin film (5) (
This is installed to determine the pattern shape of the graphite film. Below, one or more spray guns o0 fixed to the reciprocating device (9) as in the case of barrier film formation.
Graphite slurry αG supplied from the head tank (11) is spray-coated to form a heat-absorbing material thin film (5
) to form. During the above process, the glass face plate (l
A) is handled by intermittent transfer automatic operation. After completing the formation of the heat-absorbing material thin film (5) in this way, the product is then subjected to a baking treatment to complete the process of forming a fluorescent surface.

[Problem to be Solved by the Invention 3] In the method for forming a thin film of a heat-absorbing substance as described above, the glass face plate (1) is sprayed in an automatic intermittent transfer operation with a cycle of 20 seconds to 80 seconds. The nozzle hole (
The aqueous acrylic emulsion @ or graphite slurry (a) for the barrier film gradually dries and adheres around the material (2), forming a film (2) over time.

If this film-like material is formed, it may get into the gap between the nozzle hole 31) and the needle wire when the needle wire moves up and down, or it may cover the nozzle hole 3υ. Paint will not be sprayed properly. For example, since the operation is intermittent, paint leaks from the gap between the needle ■ and the nozzle hole eυ during the stoppage, and when spraying starts, it becomes droplets and splashes onto the light-reflective metal thin film (4). In addition, the spraying may become intermittent or may not be sprayed at all.

Thus, inadvertently deposited paints result in reduced luminous efficiency in the case of aqueous acrylic emulsions, and create non-luminous areas in the case of graphite slurries. If the spray condition is disturbed, the problem arises that the film thickness becomes poor and the quality deteriorates.

Furthermore, there is a problem in that it takes a lot of time to replace and clean the spray gun, making maintenance complicated.

This invention was made to solve the above-mentioned conventional problem.The nozzle of the spray gun is washed with water to prevent the paint from drying around the nozzle hole, and then the washing water adhering to the nozzle is sprayed with air. The purpose of the present invention is to provide a method for producing a thin film of a heat-absorbing material that can be removed by a heat-absorbing method, which enables proper spraying of paint and facilitates maintenance.

[Means for solving problems]

The method for producing a heat-absorbing substance thin film according to the present invention is to wash the nozzle of a spray gun with water while the intermittent operation is stopped, remove the paint adhering to the periphery of the nozzle hole with water until it dries, and then The cleaning water adhering to the nozzle is blown away with air.

[Function] In the method for producing a heat absorbing substance thin film of the present invention, the heating time is 20 seconds to 8 seconds.
Spray time is 15 during intermittent transfer automatic operation for 0 seconds.
seconds to 20 seconds, and the stop time of the spray gun is 5 seconds to 1
Since it is 0 seconds, this spray gun stop time is used to wash the spray gun with water. That is, the spray gun that has completed spraying is stopped at a fixed position, and water is discharged from the washing nozzle to the spray gun to wash the nozzle hole of the spray gun. Next, air is ejected from the air nozzle to remove water droplets adhering to the nozzle hole of the spray gun and the air cap. This can prevent water adhering to the air cap from turning into water droplets and splashing when spraying starts.

Next, aqueous acrylic emulsion (2) or graphite slurry is sprayed. In this way, since the paint is washed away with water, no paint remains around the nozzle hole, so the formation of a dry film can be prevented, and the dry paint will not get stuck in the gap between the needle and the nozzle hole. Furthermore, since the nozzle hole is not covered with a dry film, occurrences of paint splatter and uneven spraying due to paint leakage are prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, after the vapor deposition of the light-reflecting metal thin film (4) is completed, the glass face plate (1a) is placed on the holder (8) and one spray gun (1 (I) The first paint supplied from the head tank Qυ, ie, aqueous acrylic emulsion A2 (for example, an aqueous solution consisting of 1 part of Primal AC-88 manufactured by Nippon Acrylic Chemical Co., Ltd. and 5 to 15 parts of pure water) is spray applied. At this time, the spray gun position is changed to 4th by the reciprocating processor (9).
Move to the position shown in the diagram. Water is discharged from the washing nozzle (c) to the nozzle hole eυ of the spray gun α0, which is stopped at the fixed position l (FIG. 1), to perform washing. At this time, the cleaning brush holder is operated at the same time to brush the nozzle hole (c). This further enhances the cleaning effect.

Next, air is ejected from the air nozzle (7) to remove water droplets adhering to the air cap.

Next, aqueous acrylic emulsion (6) is sprayed to complete one cycle of barrier film coating. During this dry spraying, a hood (7) was installed at approximately 100 fl directly above the spray gun C1O to prevent the acrylic emulsion @ from scattering elsewhere. Although not shown, it goes without saying that an exhaust fan is provided. The water washing time was 2 seconds to 4 seconds, the air blowing time was 2 seconds to 4 seconds, and the air blowing time was 1 second to 2 seconds. Of these set times, it is better to make the dry blowing time as short as possible and the air blowing time to be longer. This is because staining of the hood (goods) is prevented and water droplets from the air cap (1) are completely removed.

Next, attach the glass face plate (la) as shown in Figure 5 (7).
Transfer the second paint, that is, the graphite slurry αQ spray position, and spray the graphite slurry (to). As the graphite slurry, for example, Aqua Duck manufactured by Acheson Co., Ltd. with a solid content of 8.5% was used.

The spraying method and the cleaning method for the spray gun QO are exactly the same as for the aqueous acrylic emulsion (2).

The reason why the spraying of the paint was particularly introduced in the above embodiments is because water that has entered the air nozzle hole 4 of the air cap (e) is difficult to remove by just blowing out air.

The above method is particularly effective and applicable to water-based paints that dry easily. It is also effective in preventing dust and dirt from accumulating on the floor due to washing liquid, and preventing dirt and dust from rolling up on the floor.

〔Effect of the invention〕

As explained above, according to the method of forming a heat-absorbing substance thin film according to the present invention, it can be cleaned within a normal cycle, there is no splashing of paint from a spray gun, and uneven spraying can be prevented, so that good images can be obtained. , an improvement in the quality of color picture tubes is realized. In addition, spray gun maintenance, which was previously performed every 1 to 2 hours, has now been reduced to about 40 to 5 hours.
0 hours, which greatly improves work efficiency.

[Brief explanation of drawings]

FIG. 1 is an explanatory view schematically showing a spray gun cleaning method according to the present invention, FIG. 2 is a cross-sectional side view showing an example of a color picture tube, and FIG. 8 is a schematic explanatory view showing a conventional barrier film manufacturing method. Figure 4 is an explanatory diagram showing the movement of the spray gun, Figure 5
The figure is a schematic explanatory diagram showing a conventional graphite slurry spraying method, and FIG. 6 is an enlarged sectional view of the main part of the spray gun. (la)... Face plate, (2)... Fluorescent surface, (4)... Light reflective metal thin film, (5)... Heat absorbing material thin film, αQ... Spray gun, ( 2)...first paint, (g)...second paint. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] (1) A first paint is applied as a barrier film using a spray gun on the light-reflecting metal thin film deposited on the fluorescent film on the inner surface of the glass face plate of the cathode ray tube, and a second paint is applied on top of it as a barrier film. In the method of forming a thin film of a heat-absorbing substance by applying the heat-absorbing material with a spray gun, the nozzles of each of the above-mentioned spray guns are washed with water, and then air is blown into the above-mentioned nozzles. A method for producing a thin film of a heat-absorbing substance, characterized in that the washing water is removed.