JPH09288969A - Manufacture of color cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color cathode-ray tube manufacturing method by which an organic film with a small thickness and few pinholes can be obtained when it is made from a water-soluble emulsion. SOLUTION: In this method, at least formation of a phosphor film 4 on the inner surface of the panel part of a color cathode-ray tube, formation of an organic film 5 by heating after application of a water-soluble emulsion onto the phosphor film 4, and deposition of an aluminum reflecting film onto the organic film 5 are effected. In this case, particles with particle diameters ranging from 10 to 20nm that are much smaller than those of known particles are used as the particles constituting the water-soluble emulsion. The use of the emulsion particles with such particle diameters markedly enhances the formability of the organic film 5, and since the film thickness can be made very thin, the amount by which cracked gases are generated from the organic film 5 and the like is decreased sharply, and a panel baking process can be omitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a color cathode ray tube, and more particularly, when an organic film is formed on a fluorescent film adhered to the inner surface of the panel portion of the color cathode ray tube, it has a uniform film quality. The present invention relates to a method for manufacturing a color cathode ray tube, which is adapted to form a thin organic film.

[0002]

2. Description of the Related Art Conventionally, one of the main process steps in manufacturing a color cathode ray tube is a first step of depositing a fluorescent film on the inner surface of a panel portion, and a fluorescent film formed in the first step. There is a second step of forming an organic film on the substrate, and a third step of depositing an aluminum reflective film on the organic film formed in the first step.

When forming an organic film in the second step, the following two methods are generally known.

In the first method, an acrylic resin is dissolved in an organic solvent such as toluene or ethyl acetate to prepare an acrylic resin solution, and the acrylic resin solution is applied to the inner surface of the panel portion of the color cathode ray tube. The second method is a method of spraying on the formed fluorescent film and then drying to form an organic film. The second method is water-soluble by using methyl methacrylate or acrylic acid having a particle size of 60 to 90 nm. An emulsion is prepared, and this water-soluble emulsion is spin-coated uniformly on the fluorescent film deposited on the inner surface of the panel of the color cathode ray tube, and then heated to a temperature above the minimum film formation temperature of the emulsion to form an organic solution. It is a method of forming a film.

[0005]

By the way, since the known first method for forming an organic film uses an organic solvent such as toluene or ethyl acetate, special safety measures and fire prevention measures are required. It is necessary to carry out, and specifically, the work place for forming the organic film needs to be separately provided with safety and fire protection measures. Therefore, there is a problem that not only the manufacturing cost of the color cathode ray tube increases but also mass production becomes difficult. In addition, if many organic solvents such as toluene and ethyl acetate are used, it may lead to the destruction of the global environment. There is also the problem of not having it.

On the other hand, since the known second method for forming an organic film uses a water-soluble emulsion, it is possible to solve the problems caused by the first method, but the water-soluble emulsion is used. When the emulsion is spin-coated on the fluorescent film, part of the water-soluble emulsion easily penetrates into the gaps of the fluorescent film, and in order to form an organic film with few pinholes, the film thickness of the organic film to be formed is It is necessary to increase the thickness to about 3 to 5 μm, which is close to 7 to 10 times the film thickness formed by the first method. And
When the film thickness of the organic film is increased, the organic substances contained in the organic film or the like are not sufficiently decomposed during the panel baking (panel baking heating) step after the aluminum reflective film is formed, and moreover, The large amount of decomposition gas generated when decomposing organic substances cannot escape through the thick organic film, and unless the organic film has a pinhole for escape of decomposition gas, the large amount of decomposition gas causes the organic film. Another problem is that the film is lifted and peeled off from the fluorescent film.

The present invention is intended to solve these problems, and an object thereof is to form a color cathode ray tube which forms an organic film having a small thickness and few pinholes when an organic film is formed using a water-soluble emulsion. It is to provide a method for manufacturing a tube.

[0008]

In order to achieve the above object, the first means according to the present invention is that the particle size of emulsion particles used when preparing a water-soluble emulsion is the particle size of emulsion particles that have been used so far. Much smaller than 1
It is intended to use the one having a thickness of 0 to 20 nm.

In order to achieve the above object, the second means of the present invention is to make the particle size of the emulsion particles used when preparing the water-soluble emulsion larger than the particle size of the emulsion particles used so far. Fine 10 to 20
The microcapsule particles containing an oxidizer are mixed with the microcapsule particles having a thickness of 10 nm.

According to the first means, the particle size of the emulsion particles used when preparing the water-soluble emulsion is set to a minute particle size within the range of 10 to 20 nm, so that the film forming property of the organic film is remarkably high. The number of pinholes per unit area is substantially the same or smaller even if the film thickness of the organic film to be formed is improved and is considerably reduced.

According to the second means, the emulsion particles used when preparing the water-soluble emulsion have a fine particle diameter within the range of 10 to 20 nm, and a microparticle containing an oxidizing agent. Since the capsule particles are mixed, as in the case of the first means, the film forming property of the organic film is significantly improved, and even if the thickness of the formed organic film is considerably reduced, The number of pinholes becomes almost equal or less, and moreover, due to the oxidant obtained by the decomposition of the microcapsule particles,
The decomposition of organic substances contained in the organic film or the like is promoted.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A method of manufacturing a color cathode ray tube according to an embodiment of the present invention includes at least a step (first step) of forming a phosphor film on an inner surface of a panel portion of the color cathode ray tube, and a fluorescent film. The method includes a step of forming an organic film by heating after applying a water-soluble emulsion on the optical film (second step), and a step of depositing an aluminum reflective film on the organic film (third step). In the water-soluble emulsion used in the second step, constituent particles having a particle diameter of 10 to 20 nm are used.

A method of manufacturing a color cathode ray tube according to another embodiment of the present invention includes at least a step of forming a phosphor film on the inner surface of the panel portion of the color cathode ray tube (first step), and a phosphor. Step of applying an aqueous emulsion on the film and then heating to form an organic film (second step)
And a step of depositing an aluminum reflective film on the organic film (third step). The water-soluble emulsion used in the second step has a particle size of 10 to 2 as constituent particles.
The microcapsule particles containing 0 nm are mixed with the oxidizing agent.

According to one embodiment of the invention,
The particle size of the water-soluble emulsion is 10
To 20 nm, the film forming property of the organic film is remarkably improved, and the formed organic film is formed even if the film thickness of the formed organic film is considerably smaller than that of the known organic film. The number of pinholes per unit area of the organic film formed by the known method of this kind, that is, the particle size thereof is 60 to 90 n.
The number can be equal to or less than the same number of pinholes as a thick organic film (known organic film) formed by using m. Since the thickness of the organic film can be made considerably smaller than that of a known organic film, organic substances contained in the organic film or the like are included in the panel baking (panel baking heating) step after vapor deposition of the aluminum reflective film. The amount of decomposition gas generated during decomposition is considerably smaller than the amount of decomposition gas from known organic films, and the panel baking (panel baking heating) step is omitted, and the subsequent heat treatment in the color cathode ray tube. At times, it becomes possible to generate such decomposed gas.

Further, according to another embodiment of the present invention, microcapsules in which the particle size of the water-soluble emulsion is 10 to 20 nm and the water-soluble emulsion contains an oxidizing agent are used. By mixing the particles, it is possible to perform the same function as in the above-described one embodiment, and at the time of the subsequent heat treatment in the color cathode ray tube, the oxidizer generated by the thermal decomposition of the microcapsule particles becomes an organic film or the like. Since it accelerates the decomposition of the contained organic matter, the decomposition of the organic matter progresses sufficiently,
As a result, even when the organic film is hit by the electron beam during actual operation of the color cathode ray tube, the decomposition gas is not emitted from the organic film, and the decomposition gas does not deteriorate the color cathode ray tube.

Here, FIG. 4 shows the particle size of the emulsion particles in the water-soluble emulsion (horizontal axis), and the film-forming property of the organic film when the organic film is formed using particles of such particle size (vertical axis). It is a characteristic view which shows the relationship with.

As shown in FIG. 4, the film-forming property of the organic film shows the best value (1) when the particle diameter of the emulsion particles constituting the water-soluble emulsion is about 20 nm or less. When the particles having a particle size of about 20 nm or more are used, the values (2 to 6) gradually deteriorate from the best value (1) in proportion to the size of the particle. On the other hand, the emulsion particles used have a particle size of about 1
If the particle size is 0 nm or less, the cohesiveness of the emulsion particles is increased, which makes it difficult to use. Therefore, in the present invention, the particle size of the emulsion particles is selected and used in the range of 10 nm to 20 nm,
The film forming property of the organic film is improved.

[0018]

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

FIG. 1 is a sectional view showing a schematic structure of a color cathode ray tube manufactured by the method for manufacturing a color cathode ray tube according to the present invention and an enlarged view of a part thereof, and FIG. 2 is shown in FIG.
FIG. 3 is an enlarged cross-sectional view showing an example of the configuration of the fluorescent film and the organic film portion in the cross-sectional view shown in FIG. Also, FIG.
It is an expanded sectional view showing an example of the composition of the organic film manufactured by the known manufacturing method of a color cathode ray tube presented in order to make a comparison with the organic film manufactured by the manufacturing method of the color cathode ray tube by the present invention.

1, 2, and 3, 1 is a panel portion, 2 is a neck portion, 3 is a funnel portion, 4 is a fluorescent film, 5
Is an organic film, 6 is an aluminum reflective film, 7 is a shadow mask, 7b is a mask frame, 8 is a magnetic shield,
9 is a deflection yoke, 10 is a magnet for adjusting the purity,
Reference numeral 11 is a center beam static convergence adjustment magnet, 12 is a side beam static convergence adjustment magnet, 13 is an electron gun, and 14 is an electron beam.

The tubular body (made of glass) constituting the color cathode ray tube has a large-diameter panel portion 1 arranged on the front side and an elongated neck portion 2 accommodating an electron gun 13.
And a funnel portion 3 having a substantially funnel shape that joins the panel portion 1 and the neck portion 2. In the panel portion 1, a fluorescent film 4 is formed on the inner surface of the front surface, an organic film 5 is formed on the fluorescent film 4, and an aluminum reflective film 6 is formed on the organic film 5. The shadow mask 7 is held by the mask frame 7b and fixedly arranged inside the panel unit 1 so as to face the fluorescent film 4. The magnetic shield 8 is fixedly arranged inside the connecting portion of the panel portion 1 and the funnel portion 3,
The deflection yoke 9 is installed outside the connecting portion of the funnel portion 3 and the neck portion 2. A purity adjusting magnet 10, a center beam static convergence adjusting magnet 11 and a side beam static convergence adjusting magnet 12 are arranged side by side outside the neck portion 2. The three electron beams 14 (only one is shown in FIG. 1) emitted from the electron gun 13 are deflected in a predetermined direction by the deflection yoke 9, and then the shadow mask 7
Through to reach the pixels of the corresponding color of the fluorescent film 4.

Since the operation of the color cathode ray tube having the above-described structure, that is, the image display operation is exactly the same as the image display operation of the known color cathode ray tube, the description of the image display operation of this color cathode ray tube will be omitted. To do.

Now, a first embodiment of a method of manufacturing the color cathode ray tube shown in FIGS. 1 and 2 will be described.

First, the following composition, that is, the average particle size is 2
An aqueous emulsion containing 15% by weight of acrylic emulsion particles, 80% by weight of glycerin, and 80% by weight of glycerin containing 80% of 0% methyl methacrylate particles and 20% of acrylic acid particles having an average particle size of 20 nm, respectively, was added. create.

Next, as is well known, a black matrix type three-color fluorescent film 4 of red, blue and green is deposited on the inner front surface of the panel portion 1 of the color cathode ray tube by a photolithography method.

Next, the deposited fluorescent film 4 is heated to 40 ° C., and then 50 ml of the water-soluble emulsion is injected into the front inner surface of the panel portion 1 so that the water-soluble emulsion is evenly spread over the front inner surface. Expand.

Subsequently, the panel portion 1 is spun at a rotational speed of 150 rpm for 20 seconds to form a thin film of a water-soluble emulsion by spin coating on the front inner surface.

Next, the thin film of this water-soluble emulsion is uniformly heated by a heater at about 45 ° C. to form an organic film 5 having an average film thickness of 0.9 μm.

Then, as is known, aluminum is vapor-deposited to a thickness of about 0.25 μm on the formed organic film 5 to form an aluminum reflecting film 6.

At this time, the formed organic film 5 is usually formed.
Approx. 430 ℃ performed on aluminum and aluminum reflective film 6 etc.
The panel baking (panel baking and heating) step at the temperature is omitted, and the process proceeds to the next step.

The release of decomposed gas from the organic film 5 and the like in the omitted panel baking (panel baking and heating) step is performed since the amount of generated decomposed gas is drastically reduced. It suffices to appropriately release them in the frit sealing step of 3, the tube sealing step, and the exhaust heat treatment step.

As is known, a frit process of thermally coupling the funnel part 3 to the panel part 1, a tube sealing process of housing and sealing the electron gun 13 in the neck part 2, a vacuum evacuation process of the tube. The color cathode ray tube is completed through various heat treatment steps.

As described above, according to the first embodiment, since the film forming property of the organic film 5 can be remarkably improved,
Even if the film thickness of the organic film 5 is made 7 to 10 times thinner than that of a known organic film, the number of pinholes per unit area can be made equal to or less than that.
Since the film thickness of the organic film 5 is considerably thin, it is possible to drastically reduce the decomposition gas released from the organic film 5 and the like by the thermal decomposition, thereby omitting the panel baking (panel baking heating) step. it can.

Next, a second embodiment of the method of manufacturing the color cathode ray tube shown in FIGS. 1 and 2 will be described.

First, the following composition, that is, the average particle size is 20:
80% of methyl methacrylate particles with a mean particle size of 2
15% by weight of acrylic emulsion particles each containing 20% of 0 nm acrylic acid particles, 0.8% by weight of microcapsule particles containing an oxidizing agent, 1.5% by weight of glycerin, and pure water as the balance. Create an emulsion.

In this case, as the microcapsule particles, those having any of the following compositions are used.

.. 5% gelatin is added to 15% hydrogen peroxide solution, the pH is adjusted to form gelatin microcapsules containing hydrogen peroxide solution, and then excess hydrogen peroxide solution is extracted. Then, a 10% formalin aqueous solution is injected into a gelatin microcapsule containing hydrogen peroxide solution, and the mixture is stirred for about 30 to harden the gelatin. Water is added to hardened gelatin microcapsules to form a microcapsule dispersion, and this dispersion is mixed to form a water-soluble emulsion. At this time, the average particle size of the gelatin microcapsules is 20 to 50 nm.
become.

.. Silver oxide with an average grain size of 10 nm (Ag
O) ultrafine particles are dispersed in 10% by weight of pure water,
Into the acrylic emulsion having the emulsion concentration of 3% used in the above Example. The water-soluble emulsion containing the microcapsule particles is rapidly stirred in a state of being heated to 50 ° C., and is kept static for 30 minutes after the stirring to form silver oxide microcapsule particles coated with an acrylic resin. After thoroughly washing the silver oxide microcapsule particles with water, water is added to form a 3% silver oxide microcapsule dispersion, and this dispersion is mixed to form a water-soluble emulsion.

.. High-pressure air is blown into a 5% aqueous solution of gelatin from a nozzle having a nozzle diameter of 1 μm to form fine bubbles. The foamed aqueous solution was heated to 80 ° C. and stirred while bubbling well with air to form microcapsule particles of gelatin containing air. A 20% formalin aqueous solution is added to the microcapsule particles containing the air and heated at 100 ° C. for 60 minutes to harden the gelatin. After thoroughly washing the hardened gelatin microcapsules with water, water is added to form a 3% microcapsule dispersion, and this dispersion is mixed to form a water-soluble emulsion.

The subsequent steps are the same as the order of steps in the first embodiment. First, on the inner front surface of the panel portion 1 of the color cathode ray tube, as is known, a black matrix type is formed by photolithography. The fluorescent films 4 of the three colors of red, blue and green are deposited.

Next, the adhered fluorescent film 4 is heated to 40 ° C., and then 50 ml of the water-soluble emulsion is injected into the front inner surface of the panel portion 1 so that the water-soluble emulsion is evenly spread over the front inner surface. Expand.

Subsequently, the panel portion 1 is spun at a rotational speed of 150 rpm for 20 seconds to form a thin film of a water-soluble emulsion on the inner surface of the front surface by spin coating.

Next, the thin film of this water-soluble emulsion is uniformly heated by a heater at about 45 ° C. to form an organic film 5 having an average film thickness of 0.9 μm.

Next, aluminum is vapor-deposited to a thickness of about 0.25 μm on the formed organic film 5 to form an aluminum reflective film 6, as is known.

At this time, the formed organic film 5 is usually formed.
Approx. 430 ℃ performed on aluminum and aluminum reflective film 6 etc.
The panel baking (panel baking and heating) step at the temperature is omitted, and the process proceeds to the next step.

The release of the decomposition gas from the organic film 5 and the like in the panel baking (panel baking heating) process which has been omitted, because the amount of the decomposition gas generated is drastically reduced, the frit process and the tube sealing process to be performed thereafter. It suffices to release them appropriately in the stopping step and the heat treatment step.

As is known, a frit step of thermally coupling the funnel portion 3 and the neck portion 2 to the panel portion 1, a tube body sealing step of housing and sealing the electron gun 13 in the neck portion 2,
A color cathode ray tube is completed through a vacuum evacuation process of the tube body and various heat treatment processes.

As described above, according to the second embodiment, the first
In the same manner as in the case of Example 1, since the film forming property of the organic film 5 can be remarkably improved, even if the thickness of the organic film 5 is reduced by about 7 to 10 times as compared with the known organic film, the unit area The number of pinholes per hit can be equal to or less than that, and since the film thickness of the organic film 5 has become considerably thin, the decomposition gas released from the organic film 5 by thermal decomposition is drastically reduced. Therefore, the panel baking (panel baking heating) step can be omitted.

Further, according to the second embodiment, the microcapsule particles mixed in the water-soluble emulsion release the oxidizing agent by thermal decomposition, and the oxidizing agent decomposes the organic substances contained in the organic film 5 or the like. Since the acceleration is promoted, the decomposed gas is not released even when the electron beam hits the organic film 5 when the color cathode ray tube is in operation, and the deterioration of the colored cathode ray tube due to the release of the decomposed gas can be prevented.

[0050]

As described above, according to the invention described in claim 1, the particle size of the emulsion particles used in the preparation of the water-soluble emulsion is much smaller than the particle size of the emulsion particles used so far. Since the film having the thickness of 10 to 20 nm is used, the film forming property of the organic film is remarkably improved, and the film thickness of the organic film to be formed can be made considerably thinner than the film thickness of the known organic film. And since the film thickness of the organic film can be made considerably thinner than the film thickness of the known organic film, the amount of decomposition gas generated by the thermal decomposition of the organic matter contained in the organic film or the like is the decomposition gas from the known organic film. The amount is significantly smaller than the amount of occurrence, and the panel baking step can be omitted.

Even if the panel baking step is omitted in the invention described in claim 1, the brightness of the displayed image in the obtained color cathode ray tube is almost the same as that of the known color cathode ray tube, and the brightness is not changed. The color could be kept below the minimum resolution.

According to the second aspect of the invention, the particle size of the emulsion particles used when preparing the water-soluble emulsion is 10 to 20 nm, which is much smaller than the particle size of the emulsion particles used so far. In addition to the effect obtained by the invention according to claim 1, the microcapsules are mixed in the water-soluble emulsion with the oxidant-encapsulating microcapsule particles. Since the oxidant generated by the thermal decomposition of the particles accelerates the decomposition of the organic substances contained in the organic film and the like, the decomposition of the organic substances is sufficiently advanced,
Even when the organic film is hit by the electron beam when the color cathode ray tube is in operation, the decomposition gas is not emitted from the organic film, and the decomposition gas does not deteriorate the color cathode ray tube.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a color cathode ray tube manufactured by a method for manufacturing a color cathode ray tube according to the present invention and an enlarged view of a part thereof.

FIG. 2 is an enlarged cross-sectional view showing an example of the configuration of the fluorescent film and the organic film portion in the cross-sectional view shown in FIG.

FIG. 3 is an enlarged cross-sectional view showing an example of the configuration of a fluorescent film and an organic film portion in a known color cathode ray tube.

FIG. 4 is a characteristic diagram showing the relationship between the particle size of emulsion particles in a water-soluble emulsion and the film forming property of an organic film.

[Explanation of symbols]

1 Panel Part 2 Neck Part 3 Funnel Part 4 Fluorescent Film 5 Organic Film 6 Aluminum Reflective Film 7 Shadow Mask 7b Mask Frame 8 Magnetic Shield 9 Deflection Yoke 10 Purity Adjusting Magnet 11 Center Beam Static Convergence Adjusting Magnet 12 Side Beam Static Convergence Adjustment magnet 13 Electron gun 14 Electron beam

Continued Front Page (72) Inventor Osamu Sasaya 3300 Hayano, Mobara-shi, Chiba Electronic Device Division, Hitachi, Ltd. (72) Toshimasa Ishigaki 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd.

Claims (2)

[Claims] 1. A step of forming a phosphor film on at least an inner surface of a panel portion of a color cathode ray tube; a step of applying a water-soluble emulsion on the phosphor film and then heating to form an organic film; A method of manufacturing a color cathode ray tube, comprising a step of depositing an aluminum reflective film on an organic film, wherein the constituent particles of the water-soluble emulsion have a particle size of 10 to 20 nm. . 2. The method for producing a color cathode ray tube according to claim 1, wherein the water-soluble emulsion is mixed with microcapsule particles containing an oxidizing agent.