JP2551242B2 - Color cathode ray tube with light selective absorption film - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube with a light selective absorption film having a light selective absorption film formed on the surface of a face plate.

[0002]

2. Description of the Related Art With the recent increase in size of color cathode ray tubes and improvement in luminance performance and focusing performance, the voltage applied to the phosphor screen of the cathode ray tube, that is, the acceleration voltage of the electron beam has increased. For example, in a conventional 21-inch class color cathode ray tube, the voltage applied to the phosphor screen is 25 to 2
The voltage was about 7 KV, but a voltage of 30 to 34 KV is applied to a recent 30-inch or more color cathode ray tube. Therefore, especially when the power of the television set is turned on and off, the outer surface of the face plate portion of the color cathode ray tube is charged up, and fine dust in the air adheres to the outer surface of the face plate portion, resulting in conspicuous dirt. Becomes easier,
As a result, it is a cause of deteriorating the luminance performance of the color cathode ray tube. Further, there is also a disadvantage that a discharge phenomenon occurs when a viewer approaches the outer surface of the face plate portion that has been charged up, and the viewer feels uncomfortable.

FIG. 6 is a graph showing changes in the surface potential of the face plate portion of the cathode ray tube when the power is turned on and off.
The characteristic curve L in the figure is the change characteristic of the surface potential when the power is on, and L1 is the change characteristic of the surface potential when the power is off.

In order to eliminate the charge-up phenomenon on the outer surface of the face plate portion of the cathode ray tube, a smooth transparent conductive film is formed on the outer surface of the face plate portion so that the charge can escape to the ground. Antistatic-treated cathode ray tubes have come into use in recent years.

FIG. 5 is a view for explaining an antistatic mechanism of the antistatic cathode ray tube. 6 is a neck portion containing an electron gun (not shown), 7 is a deflection yoke, and 13 is a funnel. , 4 is a face plate portion, 5 is a high voltage button, the deflection yoke 7 is a deflection power source via a lead wire 7a, the electron gun is a drive power source via a lead wire 6a, and the high voltage button 5 is a lead wire 5a. Are respectively connected to the high voltage power supply via.

In the cathode ray tube having the above structure, the neck portion 6
The deflection yoke 7 receives the electron beam emitted from the built-in electron gun.
Is deflected electromagnetically by the high voltage button 5, and a high voltage is applied to the fluorescent surface provided on the inner surface of the face plate portion 4 to accelerate the electron beam, and the energy causes the fluorescent surface to excite and emit light. Take the output.

Due to the influence of the high voltage applied to the fluorescent surface on the inner surface of the face plate portion 4, the outer surface of the face plate portion 4 is charged up as described above, which causes a problem such as adhesion of dust. Therefore, as a measure to eliminate such a bad effect, as shown in FIG.
Forming a smooth transparent conductive film 1 on the outer surface of the plate portion 4,
The antistatic cathode ray tube 3 has a structure in which the transparent conductive film 1 is dropped to the ground so that the charge is always released to the ground to prevent the charge-up.

In the antistatic cathode ray tube 3, the metal explosion-proof band 8 wound around the side wall of the face plate 4 and the transparent conductive film 1 are electrically connected to each other by the conductive tape 12. It is configured to drop to the ground 10A through the ground wire 10 which is hooked on the mounting ear 9 of.

Characteristic curves M and M shown by broken lines in FIG.
FIG. 1 is a diagram showing the potential change characteristics of the outer surface of the face plate portion when the power source of the antistatic cathode ray tube 3 is turned on and off, and it can be seen that the charge-up is significantly smaller than that of the conventional one. Since the smooth transparent conductive film 1 formed on the surface of the face plate 4 is required to have a certain degree of hardness and adhesiveness, a silica (SiO ₂ ) based film is generally formed.

As an example of a method for forming the silica-based smooth transparent conductive film 1, --OH groups and --O groups are used as functional groups.
An alcohol solution of silicon (Si) alkoxide having an R group is uniformly and evenly applied on the outer surface of the face plate portion 4 of the cathode ray tube by a spin coating method or the like, and then baked at a relatively low temperature, for example, 100 ° C. or lower. Since the method of performing the treatment is adopted and the smooth transparent conductive film 11 formed by such a method is porous and has a silanol group (≡Si—OH), the water content in the air is reduced. Can be adsorbed to reduce the surface resistance.

However, when such a conventional transparent conductive film 1 is baked at a high temperature, the silanol group --OH disappears and the moisture taken into the porous material also disappears, so that the surface resistance value increases. The desired conductivity cannot be obtained. Therefore, low temperature baking becomes essential, and the strength of the film is not so strong. In addition, if it is used for a long time in a dry environment, the water content in the porosity will disappear and the surface resistance value will increase with time, and once the water content has gone out of this porosity, it will be difficult to get in again and it will not recover. . As described above, the conventional transparent conductive film 1 has a large defect in terms of film strength and stability of resistance value over time.

In order to improve such drawbacks, it has been attempted to impart conductivity by binding a metal atom such as zirconium (Zr) to the alkoxide structure in the coating solution.
No significant improvement could be expected.

As a method capable of fundamentally solving these problems, fine particles of tin oxide (SnO ₂ ) or indium oxide (In ₂ O ₃ ) as a conductive filler are mixed and dispersed in the alcohol solution of silicon alkoxide. At the same time, a coating liquid containing a small amount of phosphorus (p) or antimony (Sb) for imparting semiconductor properties is uniformly and smoothly applied to the outer surface of the face plate portion 4 of the cathode ray tube.
There is a method of performing a baking process at a relatively high temperature, for example, 100 ° C to 200 ° C. According to this method, a smooth transparent conductive film 1 having a strong film strength and a resistance value which does not change with time under any environment can be obtained.

Conventionally, the antistatic treatment of the color cathode ray tube has been performed by such a method, but with the recent strong demand for high image quality of a color television receiver, the transparent conductive film 1 is colored to color. A method of simultaneously improving the contrast and emission color tone of the cathode ray tube has begun to be put into practical use.

That is, a coating solution for obtaining the conventional transparent conductive film 1 is used as a base coating material, and an organic or inorganic dye is mixed therein to prepare a colored photoselective absorption coating solution, which is spin-coated similarly to the conventional example.・ Coating method or the like is applied to the outer surface of the face plate of the color cathode ray tube to form a film, thereby forming a color cathode ray tube with a light selective absorption film having an antistatic function.

FIG. 7 is a diagram showing the structure of the color cathode ray tube 11 with the antistatic treatment type photoselective absorption film. In the conventional antistatic treatment type shown in FIG. 5, except for the antistatic treatment type photoselective absorption film 2. It is the same as the cathode ray tube 3.

FIG. 4 is a diagram for explaining the optical characteristics of the conventional antistatic light-selective absorption film 2. The characteristic curve B in the drawing is a blue-emitting sulfide system on the fluorescent surface of the color cathode ray tube. Phosphor, for example, silver activated zinc sulfide phosphor (Zn S: Ag)
Shows a spectral distribution characteristic of relative emission intensity of about 450
It has a dominant spectral wavelength in nm. In addition, the characteristic curve G
Is a green-emitting sulfide-based phosphor such as gold, copper, and aluminum co-activated zinc sulfide phosphor (Zn S: Au, Cu, A).
l) shows the spectral distribution characteristics of relative emission intensity,
It has a dominant spectral wavelength at 35 nm. Similarly, the characteristic curve R shows the spectral distribution characteristic of the relative emission intensity of the red-emitting rare earth-based phosphor, for example, the europume activated yttrium oxysulfide phosphor (Y ₂ O ₂ S: Eu), which is about 626 nm.
Has a main spectral wavelength. Also, characteristic curve II and
III shows the spectral transmittance distribution of the face plate 4 on which the fluorescent screen of the color cathode ray tube is formed. Characteristic curve II is a clear type with a spectral transmittance of about 85% in the visible light region, characteristic curve III. Indicates the spectral transmittance distribution of the Taint type face plate 4 of 50%.

The lower the spectral transmittance of the face plate 4, the more disadvantageous the luminance performance of the fluorescent screen of the color cathode ray tube. This is clear from the relationship with the spectral distribution of the relative emission intensities of the B, G, and R phosphor screens. However, external light incident on the fluorescent surface of the color cathode ray tube can be effectively removed, which is advantageous in contrast performance. For this reason, in recent color television receivers, the taint type face plate 4 is often used from the viewpoint of emphasis on image quality.

A characteristic curve I in the figure shows an example of the spectral transmittance distribution characteristic of the antistatic treatment type light selective absorption film 2 provided for improving the contrast performance, and the spectrum of the relative emission intensities of G and R. Distribution main spectrum between wavelengths 535
nm to 626 nm, the absorption peak A of the antistatic treatment type light selective absorption film 2 is in a portion close to the main spectrum wavelength.
Since there is a disadvantage in the luminance performance of the fluorescent surface of the color cathode ray tube, it is usually 570n in consideration of the full width at half maximum of this absorption band.
The absorption peak A of the absorption band is located in the range of m to 610 nm. This is because light with a wavelength in this range matches the region where the human eye has relatively high visibility, so if the light in this region of the external light (white light) component is absorbed and removed, the contrast performance is improved. This is because it is preferable.

That is, regarding the optical characteristics of the conventional antistatic treatment type light selective absorption film 2 of the conventional antistatic treatment type color selective cathode ray tube 11, the human eyes have a relatively high visual sensitivity, and the optical characteristics Absorption peak A in the absorption band in the range of 570 nm to 610 nm, which has the least effect on the emitted light flux.
Is arranged so as to effectively absorb outside light while maintaining the brightness performance of the phosphor screen and improve the contrast performance. It is very important to select an organic or inorganic dye having such optical characteristics.
This is an example in which the absorption peak A of the absorption band is given to 80 nm.

In such a color cathode ray tube 11 with an antistatic treatment type photoselective absorption film, the organic and inorganic dyes mixed in the base paint have a relatively broad optical light absorption characteristic, so that the fluorescent screen For example, in the case of green light emission, the tail portion on the long wavelength side of the main spectrum wavelength is absorbed by the light emission, and in the red light emission, the sub-peak portion on the short wavelength side of the main spectrum wavelength is absorbed by the light selective absorption film. You can also do it.

FIG. 8 is a sectional view of the antistatic treatment type light selective absorption film 2 thus formed on the surface of the face plate portion 4. The antistatic treatment type light selective absorption film 2 is porous. Dye particles or molecules 13 are dispersed in a silica (SiO ₂ ) film 14. This dye particle or molecule 13 has a great problem in weather resistance, and particularly when an organic dye is used, fading due to ultraviolet rays is very large.

Originally, the dye is one which is chemically bonded to the protein or cellulose constituting the fibers of the cloth or the like to be stabilized, whereas the dye is contained in the porous silica (SiO ₂ ) film 14. In the case of the conventional example dispersed in, there is no partner to chemically bond, it is unstable because it exists as dye particles or molecules alone, and porous silica (dye particles or molecules are dispersed) ( This is because the SiO ₂ ) -based film 14 is in a strongly acidic state, so that it is easily decomposed and deteriorated by the energy of ultraviolet rays and fading easily occurs.
This porous silica (SiO ₂ ) based film 14 exhibits strong acidity because the photoselective absorption coating liquid itself is strongly acidified by hydrochloric acid ( HCl ) or the like in order to form a stable film.
This is because it has been adjusted to about 2.3).

That is, the alcohol solution of silicon (Si) alkoxide, which is the base paint of the photoselective absorption coating liquid, starts with ethyl silicate shown in a, for example, as in the chemical reaction formula shown in Chemical formula 1 in the process of film formation. B, c as points
As shown in the above, while undergoing a hydrolysis reaction and a dehydration reaction by heating, it changes into a porous silica (SiO ₂ ) film 14, and hydrochloric acid ( HCl ) is used as a catalyst for promoting each of these reactions. Since it is added, the coating liquid and the coating film formed from it show strong acidity.

[0025]

Embedded image

In a general household, since the color television receiver is used indoors in most cases, the intensity of ultraviolet rays received from the surroundings is not so strong. But,
When a color television receiver is installed near the window for a long period of time, the dye of the antistatic treatment type light selective absorption film 2 may be discolored by ultraviolet rays in sunlight.

FIG. 3 is a diagram for explaining a method of evaluating the weather resistance to ultraviolet rays of such an antistatic-type photoselective absorption film 2, which is located 30 cm from the mercury lamp 15 for fading test. The face plate 4 on which the selective absorption film 2 is formed is placed, and strong ultraviolet rays from the mercury lamp 15 for fading test are applied to the sample for a certain period of time to forcibly cause fading. FIG. 4 is a diagram showing changes in the spectral transmittance distribution of the antistatic treatment type light selective absorption film 2 before and after this ultraviolet exposure test. In the case of the antistatic treatment type light selective absorption film using a certain dye, the characteristic curve I As shown, the transmittance at the absorption peak A in the absorption band at 580 nm is 70.0% at first, but when it is exposed to ultraviolet rays having an intensity of about 3.5 mW / cm ² for about 13 hours, the dye is discolored. The position of the absorption peak changes to A _1, that is, 80.0% as indicated by the characteristic curve I V shown by the broken line. Letting ΔT% be the absorption depth, the absorption depth ΔT changes from 25% to 15% ΔT ₁ before and after the exposure test.

The characteristic curve V in FIG. 2 shows how the absorption depth ΔT% changes with the exposure time when the conventional antistatic-treated photoselective absorption film using a certain dye is subjected to the ultraviolet exposure test. In the figure showing that, it shows a large fading phenomenon of 24% in 50 hours.

[0029]

As described above, in the conventional color cathode ray tube with the light selective absorption film, the dye dispersed in the light selective absorption film gradually fades due to ultraviolet rays in the external light. Therefore , there is a problem in that the light selective absorption characteristic is deteriorated and the degree of improvement in contrast performance and emission color tone is reduced. An object of the present invention is to obtain a color cathode ray tube provided with a photoselective absorption film in which fading of a dye due to ultraviolet rays contained in outside light such as sunlight does not easily occur.

[0030]

A color cathode ray tube with a photoselective absorption film according to the present invention is chemically mixed with an organic or inorganic dye in a coating liquid used for forming a photoselective absorption film. An organic stabilizing substance that binds and stabilizes is mixed and decomposed, and a photoselective absorption film formed by using this coating liquid is provided.

[0031]

According to the present invention, the organic or inorganic dye in the photoselective absorption film is chemically bonded and stabilized with the organic stabilizing substance. Therefore, even if ultraviolet rays enter the light selective absorption film, the dye in the film is less likely to be discolored.

[0032]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partially enlarged sectional view including an antistatic light-selective absorption film 2 formed on the surface of the face plate portion 4. In the figure, 16 is an organic stabilizing substance that chemically bonds with and stabilizes the organic or inorganic dye particles or molecules 13, and is added and mixed in the coating liquid to be applied and film-formed to prevent electrostatic charge. It is formed on the processing type light selective absorption film 2. Therefore, the dye particles or molecules 13 dispersed in the porous silica (SiO ₂ ) -based film 14 do not exist independently as in the conventional antistatic-treated photoselective absorption film 2, but rather as an organic material. It is a very stable substance that is chemically bound to the stabilizing substance 16 of the system.

Examples of such stabilizing substances include cellulose (fibrin) which is a main component of plant cell walls and derivatives thereof, polysaccharides such as starch, glycogen, inulin, pectin, and plant gum, and monosaccharides and raw sugars. Proteins and peptides, which are organic polymer substances containing nitrogen, which is a major component of cells, and crystalline polymer substances having a high melting point, which are substances that can be synthetic fibers, can be used.

The characteristic curve V in FIG. 2 shows the result of the ultraviolet exposure test of the conventional antistatic treatment type light selective absorption film 2 in which the organic stabilizing substance 16 is not added and mixed as described above. , Absorption residual rate 4% in 50 hours (1/25 × 10
0 = 4), that is, a large change, that is, a fading phenomenon.

On the other hand, the characteristic curve VI in FIG. 2 shows that the dye contained in the coating liquid in the conventional selective light-selective absorption coating liquid for forming the antistatic light-selective absorption film 2 is Starch, which is a kind of polysaccharide, is added and mixed in a weight ratio of 1: 1 and the result of the ultraviolet exposure test of the antistatic-treated photoselective absorption film 2 coated and film-formed using this coating liquid is shown. so,
The absorption residual rate after 50 hours is 64% (16/25 × 100
= 64), a significant improvement is made compared to the conventional example.

In the above examples, starch was used as the organic stabilizing substance, but the present invention is not limited to this. The degree of effect of various organic substances as described above depends on the material and the amount added. Although slightly different, the same effect can be obtained.

In the above embodiment, the organic stabilizing substance 16 is added and mixed in the photoselective absorption coating liquid for forming the antistatic treatment type photoselective absorption film 2. It is also possible to prepare a photoselective absorption coating liquid by mixing the organic dye with the organic stabilizing substance 16 to stabilize it, and then mixing it with the organic or inorganic base paint. , The same effect can be obtained.

Further, in the above-mentioned embodiment, the antistatic treatment type photoselective absorption film in which the transparent conductive film of the antistatic treatment type color cathode ray tube is mixed with the organic or inorganic dye to have the photoselective absorption characteristic. However, the present invention is not limited to this example, and a color with a light selective absorption film having only a light selective absorption function without an antistatic function is described. The same effect can be obtained by applying the same to a cathode ray tube.

[0039]

As described above, according to the present invention, the organic or inorganic dye and the chemical dye are chemically mixed in the base paint in which the organic or inorganic fine particles or molecules are dispersed. Since it is a color cathode ray tube with a light selective absorption film equipped with a light selective absorption film formed by applying and forming a coating liquid in which an organic stabilizing substance that binds to and stabilizes it, In addition, there is an effect that a color cathode ray tube with a photoselective absorption film, which is excellent in quality and durability with less discoloration phenomenon, can be obtained.

[Brief description of drawings]

FIG. 1 is a partially enlarged sectional view of a face plate portion according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing the results of ultraviolet exposure of Examples and Conventional Examples.

FIG. 3 is a diagram for explaining a weather resistance evaluation method against ultraviolet rays.

FIG. 4 is a diagram showing optical characteristics of a light selective absorption film.

FIG. 5 is a diagram showing the configuration of an antistatic color cathode ray tube with a transparent conductive film.

FIG. 6 is a view when the power source of the color cathode ray tube is turned on and off.
The figure which shows the change of the surface potential of a spray part.

FIG. 7 is a diagram showing a configuration of an antistatic treatment type color cathode ray tube.

FIG. 8 is a partially enlarged sectional view of a face plate portion of a conventional cathode ray tube of antistatic treatment type.

[Explanation of symbols]

2 Light Selective Absorption Film 4 Phase Plate 11 Anti-Static Color Cathode Ray Tube 13 Dye Particles or Molecules 14 Porous Silica ( _Si O ₂ ) Film 16 Organic Stabilizer

Claims (1)

(57) [Claims] 1. A color cathode ray tube comprising a porous silica-based light selective absorption film in which an organic or inorganic dye is dispersed, wherein the dye is chemically bonded to the dye in the light selective absorption film. A color cathode ray tube with a photoselective absorption film, characterized in that an organic stable substance for stabilizing is dispersed.