KR20010001110A - Structure phosphor layer and method manufacturing that in color CRT - Google Patents

Abstract

PURPOSE: A structure of a fluorescent film in a color CRT(Cathode Ray Tube) and a production method thereof are provided to simplify a producing process of the fluorescent film and to improve the contrast characteristic, the brightness and the color reproducibility of a screen. CONSTITUTION: A mixed filter slurry(3gb) is spread inside a panel(1) having a black matrix(2) and dried. The mixed filter slurry(3gb) contains a mixed pigment dispersed solution, a PVA(polyvinyl alcohol), an ADC/SDC(Ammonium/Sodium Dichromic Acid). The mixed pigment dispersed solution disperses a CoO-Al2O3, a ZnO-TiO2-NiO-CoO and a Fe2O3 with pure water. Portions to form green/blue fluorescent layers(4G,4B) are exposed by ultraviolet rays. A mixed filter layer(3GB) is formed in green/glue positions by developing the portions with pure water. Three-color fluorescent layers are formed by three-color fluorescent members.

Description

Structure phosphor layer and method manufacturing that in color CRT

The present invention relates to a fluorescent film of a color cathode ray tube, and more particularly to a structure and a method of forming a fluorescent film for improving the brightness characteristics, contrast characteristics and color reproducibility of the screen.

In general, a color cathode ray tube is a device that implements an image by hitting a fluorescent film formed on the inner surface of the panel by the electron beam emitted from the electron gun. Recently, as the screen is enlarged and high in size, an improved luminance characteristic and a contrast characteristic are required. Efforts are being made to

For example, to reduce light reflection to external light and obtain high contrast characteristics, a dark glass having a light transmittance of about 36 to 55% is used, or a phosphor in which inorganic pigments of the same color are attached to the surface of phosphor particles. There may be a method of forming a fluorescent film, or a method of improving selective transmission characteristics by forming a same-color three-color filter layer between a glass panel on which a black matrix film is formed and a three-color phosphor layer.

Among them, the color cathode ray tube in which the panel is formed using dark glass has a low light transmittance, which is advantageous for the contrast characteristic, whereas the luminance characteristic of the color cathode tube is absorbed by the panel.

In the case of a color cathode ray tube in which a phosphor film is formed using a phosphor with a pigment attached thereto, the contrast is improved because the external light is absorbed by the pigment, but when the phosphor film is formed, a part of the light emission from the phosphor particles is overlapped. Absorption by the pigment lowers the luminance characteristic, pigment particles interfere with the phosphor core collision of the electron beam, there is a problem that the luminance decreases.

In order to solve this problem, there is a fluorescent film in which a three-color filter layer as shown in FIG. 1 is formed.

The fluorescent film in which the three-color filter layer shown in FIG. 1 is formed is demonstrated as an example of the conventional color cathode ray tube fluorescent film.

In the fluorescent film having the three-color filter layer formed thereon, three-color filter layers 3R (3G) and 3B are formed on the upper surface of the panel 1 on which the black matrix 2 is formed, and the three-color phosphor layers 4R and 4G are formed thereon. (4B) was formed.

That is, in the panel 1 having a light transmittance of 70 to 85%, red, green, and blue three-color filter layers 3R, 3G, and 3B of the same color as the three-color phosphors are formed, and the three-color filter layer 3R is formed thereon. The red, green, and blue three-color phosphor layers 4R, 4G, and 4B corresponding to the respective colors of the 3G and 3B are formed.

At this time, the three-color filter layer (3R) (3G) (3B) is applied to the polyvinyl alcohol (PVA), a slurry in which the particulate pigment is dispersed in a photosensitive liquid such as sodium dichromate (SDC) or ammonium dichromate (ADC), and then dried. It is formed by attaching a shadow mask (not shown) to ultraviolet light and developing it, or after applying and drying a photoresist such as polyvinyl alcohol (PVA), sodium dichromate (SDC) or ammonium dichromate (ADC), A shadow mask was inserted to expose the area where each filter layer is to be formed with ultraviolet light, and then photocured and developed to form a PVA layer. Then, a rust filter dispersion was applied and dried on the film, followed by etching with an oxidized water such as hydrogen peroxide solution. 3G), and the red, green, and blue color filter layers 3R, 3G, and 3B are formed in the same manner.

Reference numeral 5 in the drawings denotes an aluminum film for preventing the rearward departure of the electron beam and reflecting the light emitted in the backward direction in all directions, and 6 is a colored coating film (film film) for improving the contrast of the screen.

As such, when the three-color filter layers 3R, 3G, and 3B are applied to the fluorescent film of the color cathode ray tube, the contrast and luminance can be improved by about 10 to 20% compared to the color cathode ray tube using the phosphor with pigment. .

According to Japanese Patent Laid-Open No. 9-27284, the three-color filter layers 3R, 3G, and 3B are wavelengths in the range of about ± 20 nm of the maximum emission spectrum wavelengths of the corresponding three-color phosphor layers 4R, 4G, and 4B. It has been suggested that it has the maximum transmittance for light and has a relatively low transmittance for the other light wavelength range, and thus it is possible to improve the contrast characteristics of the cathode ray tube, and as shown in FIG. The light emitting region of each of the filter layers 3R (3G) and 3B with respect to the light emitting region of the phosphor layers 4R (4G) 4B has a spectrum having an effective transmittance in the maximum light emitting region of each phosphor.

Specifically, the blue filter layer 3B has a transmittance of about 70% at 450 nm, which is the maximum light emitting region, of the light emitting region of the blue phosphor layer 4B, and the red phosphor layer 4R in the red filter layer 3R. Has a transmittance of about 60% near the maximum emission region of 625 nm, and the green filter layer 3G has a transmittance of about 70% near the maximum emission region of 535 nm of the emission region of the green phosphor layer 4G. It can be seen that it has a transmittance.

However, forming the respective filter layers 3R, 3G, and 3B for each phosphor as described above is advantageous for the improvement of contrast characteristics and luminance characteristics, but each filter layer 3R (3G) ( Since a dedicated apparatus for forming a filter and a plurality of filter forming steps are required to form 3B), there is a problem that the cost is increased and the productivity is greatly reduced.

Therefore, a fluorescent film is proposed which simplifies the formation process while keeping the contrast and luminance characteristics substantially the same as those of the above-described fluorescent film on which the three-color filter layers 3R (3G) and 3B are formed. Likewise, only the blue filter layer 3B is formed on the inner surface of the panel 1 having a light transmittance of 45 to 75%, and the three-color phosphor layers 4R, 4G, and 4B are formed at respective positions. ) Or only the blue filter layer 3B, and the three-color phosphor layer 4R (4G) (4B) is formed at each position, but the red phosphor is formed by using the red phosphor having a large amount of the red pigment 7 at the red position. The method of forming the layer 4R, and the like.

Since the blue filter layer 3B of the fluorescent film is formed by the same process as that of forming the three-color filter layers 3R, 3G, and 3B, the number of processes can be reduced by about 2/3, and the brightness and contrast characteristics In comparison with the fluorescent film using a phosphor with a pigment, it was confirmed that there is an improvement effect of about 10% in the former case and about 10 to 15% in the latter case.

However, only the above-described fluorescent film, that is, the blue filter layer is formed, and only the fluorescent film and the blue filter layer having the three-color phosphor layer formed at each position are formed, and the three-color phosphor layer is formed at each position, but a large amount of red pigment is attached to the red position. Phosphor films or the like, which form red phosphor layers using red phosphors, have the effect of reducing the number of processes in terms of their formation process, but are not yet practically used due to their insufficient characteristics.

Accordingly, the present invention has been proposed in view of the above, and provides a fluorescent film structure and method for forming a color cathode ray tube for simplifying a fluorescent film forming process and improving contrast, brightness, and color reproducibility of a screen. Its purpose is to.

1 is a cross-sectional view of a fluorescent film of Embodiment 1 of a conventional color cathode ray tube, in which a three-color filter layer is formed;

FIG. 2 is a graph showing reflection spectra of each filter layer and each phosphor layer applied to FIG. 1;

2A is a reflection spectrum graph of a blue filter layer and a blue phosphor layer;

2b is a reflection spectrum graph of a red filter layer and a red phosphor layer;

Figure 2c is a reflection spectrum graph of the rust filter layer and the rust phosphor layer,

3 is a cross-sectional view of a fluorescent film of a conventional color cathode ray tube, in which only a blue filter layer is formed;

4 is a cross-sectional view of a fluorescent film of a conventional color cathode ray tube, in which only a blue filter layer is formed and a red phosphor layer is formed using a phosphor having a large amount of pigment attached thereto;

Figure 5a is a graph showing the transmission spectrum of the mixed filter layer according to the present invention,

5b is a graph showing the reflection spectrum of the red phosphor layer according to the present invention,

6 is a process chart for forming a mixed filter layer according to the present invention,

7 is a cross-sectional view of a fluorescent film of a color cathode ray tube according to the present invention;

8 is a graph comparing color implementation of the color cathode ray tube according to the present invention with a conventional product through CIE color coordinates.

*** Explanation of symbols for main parts of drawing ***

1 panel 2 black matrix

3GB: mixed filter layer 4R: red phosphor layer

4G: green phosphor layer 4B: blue phosphor layer

5: aluminum film 6: colored coating film (film film)

7: red pigment

In order to achieve the above object, the fluorescent film structure of the color cathode ray tube according to an aspect of the present invention includes a black matrix as an external light absorbing layer formed on an upper surface of a panel having a predetermined light transmittance, and an upper surface of the panel on which the black matrix is formed. CLAIMS 1. A fluorescent film of a color cathode ray tube in which red, green, and blue phosphor layers, which are light emitting pixels, are formed: (1) the red phosphor layer comprises a red phosphor having red pigment of fine particles attached thereto; (2) at least one of red and green and blue are mixed between the blue phosphor layer and the panel and between the green phosphor layer and the panel such that the light transmittance at wavelengths of 450 nm and 535 nm is 60% or more; Characterized in that two or more mixed filter layers are formed.

Preferably, the red phosphor is attached to the red pigment 1wt% or more, and the blue phosphor constituting the blue phosphor layer is characterized in that the blue pigment is attached to 1wt% or less.

Preferably, the panel is characterized in that the light transmittance is 40 to 85%.

Optionally, when the light transmittance of the panel is 40 to 60%, an outer coating film (film film) is formed on the outer surface of the panel which does not occur in the light transmittance, or when the light transmittance of the panel is 60 to 85% of the panel The outer surface is characterized in that a color coating film (film film) containing a color pigment for reducing light transmittance is formed.

According to another aspect of the present invention, a method for forming a fluorescent film of a color cathode ray tube includes: a black matrix as an external light absorbing layer, a filter layer having light selective transmission characteristics, and a phosphor forming pixels on an inner surface of a panel having a predetermined light transmittance; A method of forming a fluorescent film of a color cathode ray tube in which a layer is sequentially formed, comprising: (1) mixing a mixed filter slurry liquid containing a mixed pigment dispersion liquid in which at least one of a predetermined red pigment and a green pigment and a predetermined blue pigment are dispersed; Applying to green and blue positions on the inner surface of the panel and exposing and developing to form a mixed filter layer; (2) forming a red phosphor layer using a red phosphor having a predetermined red pigment attached thereto; And (3) alternately forming a blue phosphor layer and a green phosphor layer on an upper surface of the mixed filter layer.

Preferably, the red pigment comprises iron oxide (Fe ₂ O ₃ ), the green pigment comprises cobalt green (ZnO-TiO ₂ -NiO-CoO), the blue pigment is cobalt blue (CoO-Al ₂ O ₃ ) It is characterized by including.

Preferably, as the red pigment attached to the red phosphor, a particle diameter of 200 nm or less is used, and each pigment added to the mixed pigment dispersion is characterized by using a particle size of 100 nm or less.

Preferably, the red phosphor is characterized in that the red pigment attached to at least 1wt%.

Preferably, each pigment is added to the mixed pigment dispersion in a content ratio of 5 to 20 wt%.

Optionally, when the pigment is added to the mixed pigment dispersion in a content ratio of 5 wt% or less, the blue phosphor constituting the blue phosphor layer is characterized by attaching a blue pigment at 1 wt% or less.

Preferably, the panel is characterized by using a light transmittance of 40 to 85%.

Optionally, when the panel has a light transmittance of 40 to 60%, an outer surface coating film (film film) is formed on the outer surface of the panel which does not cause light transmittance deterioration, or the panel has a light transmittance of 60 to 85%. In this case, the outer surface of the panel is characterized by forming a colored coating film (film film) containing a color pigment for reducing the light transmittance.

In this way, in forming the fluorescent film of the color cathode ray tube, the filter forming process can be reduced, which simplifies the manufacturing process and improves workability and productivity, and the dominant wavelength region of green emission color is made into the short wavelength region by the mixed filter layer. Since it can be moved, color reproducibility can be improved, and high contrast characteristics can be realized by the red pigment and the mixed filter layer attached to the red phosphor, and high luminance characteristics can be realized by the blue phosphor layer.

And, there may be a plurality of embodiments of the present invention, hereinafter will be described in detail with respect to the most preferred embodiment.

This preferred embodiment allows for a better understanding of the objects, features and advantages of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the structure and method of forming a fluorescent film of the color cathode ray tube according to the present invention, in the drawings used in the description In this case, the same reference numerals are given to the same numerals, and duplicate description thereof may be omitted.

Figure 5a is a graph showing the transmission spectrum of the mixed filter layer according to the present invention, Figure 5b is a graph showing the reflection spectrum of the red phosphor layer according to the present invention, Figure 6 is a process chart of forming a mixed filter layer according to the present invention, Figure 7 is a cross-sectional view of a fluorescent film of a color cathode ray tube according to the present invention, and FIG. 8 is a graph comparing color implementation of the color cathode ray tube according to the present invention with conventional products through CIE color coordinates.

The color cathode ray tube according to the present invention has a conventional structure in order to improve the color purity characteristics of each phosphor layer while expressing almost the same contrast and luminance characteristics without forming a color filter all of the phosphor layers and the same color series. Two or more mixed filter layers were formed in place of the blue filter layer and the green filter layer.

That is, after two or more mixed filter layers are formed in the blue and green positions among the spaces between the black matrices, the blue phosphor layer and the green phosphor layer are alternately formed on the upper surface of the mixed filter layer, and a large amount of pigment is attached to the remaining space. It is to form a red phosphor layer by using a phosphor, wherein the mixed filter layer should be formed such that the light transmittance at 450 nm which is the main wavelength of the blue phosphor layer and 535 nm which is the main wavelength of the green phosphor layer is 60% or more as shown in FIG. 5A. To the red phosphor, as shown in FIG. 5B, the red pigment should be properly attached so that the light reflectance at 580 nm or more is increased.

Hereinafter, this will be described in detail with reference to FIGS. 6 to 8.

First, as shown in FIG. 6, cobalt green of fine particles of green pigments is composed mainly of cobalt blue (CoO-Al ₂ O ₃ ) of fine particles of blue pigment on the inner surface of the panel 1 on which the black matrix 2 is formed. ZnO-TiO ₂ -NiO-CoO) or a mixed pigment dispersion obtained by dispersing fine iron oxide (Fe ₂ O ₃ ) as a red pigment with pure water and a dispersant, polyvinyl alcohol (PVA), and ammonium dichromate (ADC) as a photoresist Alternatively, a mixed filter slurry (3 GB) containing sodium dichromate (SDC) is applied and dried, and a portion of the rust phosphor layer 4G and the blue phosphor layer 4B is exposed to ultraviolet rays, followed by using pure water. It is developed by pressure to form a mixed filter layer (3GB) in green and blue positions.

At this time, the concentration of cobalt blue (CoO-Al ₂ O ₃ ) and cobalt green (ZnO-TiO ₂ -NiO-CoO) or iron oxide (Fe ₂ O ₃ ) added to the mixed pigment dispersion is about 5 to 20wt%. If the concentration is 5wt% or less, the permeability of the mixed filter layer (3GB) is weak to obtain a desired selective permeation effect. If it is 20wt% or more, it is difficult to disperse the pigment of the fine particles and the filter permeation property is too strong. Although the transmission characteristic is improved, there is a problem that the luminance is greatly reduced.

In addition, cobalt blue (CoO-Al ₂ O ₃ ), cobalt green (ZnO-TiO ₂ -NiO-CoO), and iron oxide (Fe ₂ O ₃ ) added to the mixed pigment dispersion should use a particle diameter of 100 nm or less. In addition, when the particle diameter is 100 nm or more, the particles are too large to make a clean filter difficult, and the filter surface is roughened, thereby reducing the selective transmission characteristics.

After forming the mixed filter layer (3GB) as described above, to form a three-color phosphor layer (4R) (4G) (4B) by a conventional slurry method using a three-color phosphor, the red phosphor layer to improve the contrast characteristics (4R) uses a phosphor to which a large amount of iron oxide (Fe ₂ O ₃ ), which is a red pigment 7, is attached.

In this case, the pigment adhesion amount of the red phosphor should be 1wt% or more. If the pigment adhesion amount of the red phosphor is 1wt% or less, the amount of selectively transmitted when external light is reflected from the red phosphor layer is insufficient, resulting in insufficient contrast enhancement effect.

In addition, it is preferable to use the red pigment 7 attached to the red phosphor having a particle size of 200 nm or less. If the particle size of the red pigment 7 is 200 nm or more, the particles are so large that the external light absorption effect is inferior.

On the other hand, when applying a pigment concentration of 5wt% or less to the mixed pigment dispersion to form a mixed filter layer (3GB) cobalt blue (CoO-Al ₂ O ₃ ), a blue pigment to improve the selective transmission characteristics of the blue region The blue phosphor layer 4B can be formed using a small amount of attached blue phosphor.

At this time, cobalt blue (CoO-Al ₂ O ₃ ) attached to the blue phosphor is preferably applied to 1wt% or less with respect to the weight of the phosphor, and if the adhesion amount is 1wt% or more, the amount of pigment is too high in the phosphor particles Part of the emission of light is absorbed by the pigment, and the luminance characteristic is lowered. When driving the color cathode ray tube, a large amount of current is consumed in the blue color, thus shortening the life of the color cathode ray tube.

In this way, the filter forming process is simpler than that of forming the filter layers in the same color series as the conventional green, blue, and red positions, thereby reducing material costs and improving productivity.

In addition, the mixed filter layer 3GB is formed such that the average light transmittance at 450 nm which is the main emission wavelength region of the blue phosphor layer 4B and 535 nm which is the main emission wavelength region of the green phosphor layer 4G is 60% or more. In this case, high light transmittance is exhibited in the vicinity, and high contrast can be realized by absorbing external light in other regions.

In addition, the mixed filter layer (3GB) has a high light absorption in the wavelength range of 550 ~ 630nm most visible, so that the light from both the light emitted from the blue phosphor layer 4B and the light emitted from the green phosphor layer 4G Since the transmittance is high, the luminance decrease is small, and the light absorption rate of the 550-630 nm wavelength region with respect to the external light is high, thereby reducing the external light reflection of the screen, thereby improving both the luminance characteristic and the contrast characteristic.

FIG. 8 compares the color implementation according to the present invention with CIE color coordinates according to the present invention, and the filter structure according to the present invention is compared with the conventional structure applying the blue filter layer 3B and the green filter layer 3G, respectively. In terms of the luminance characteristics and contrast characteristics, the selective absorption state of the light emitted from the green phosphor layer 4G by the mixed filter layer 3GB formed at the blue and green positions is approximately 3 GB. Since the light transmittance of the short wavelength region is higher than that of the green filter layer 3G, the emission color of the green phosphor layer 4G can be shifted to the green region, resulting in excellent green reproducibility.

Here, the color coordinates of the prior art and the present invention are shown in Table 1 below.

TABLE 1

Classification location enemy rust blue Conventional x 0.632 0.275 0.143 y 0.334 0.602 0.067 Invention x 0.637 0.260 0.145 y 0.330 0.610 0.058

On the other hand, as the panel 1 on which the mixed filter layer 3GB and the phosphor layers 4R, 4G, and 4B are formed, it is preferable to use a 40 to 85% transmittance higher than the conventional one. In this case, the red phosphor layer 4R and the mixed filter layer (3GB) having a large amount of red pigment 7 greatly improve the contrast characteristics, but the brightness is severely deteriorated. The transmittance is too high and the luminance characteristic is greatly increased, but the contrast characteristic is greatly reduced.

Therefore, when the light transmittance of the panel 1 is 40 to 60%, it is preferable to form an outer coating film (film film) on the outer surface of the panel 1 in which the light transmittance decreases, and the light transmittance of the panel 1 is In the case of 60 to 85%, it is preferable to form a colored coating film (film film) 6 containing a color pigment for reducing light transmittance on the outer surface of the panel 1. At this time, the colored coating liquid for forming the colored coating film 6 should be formed to have a low transmittance, and care should be taken to form a uniform colored coating film (film film) 6 that does not cause stains after coating.

Finally, when the three-color phosphor layer 4R (4G) (4B) is formed, when the aluminum film 5, which is a metal reflective film for preventing the rearward deviation of the electron beam, is deposited on the upper surface thereof, the fluorescent film is finally formed as shown in FIG. Is completed.

Table 2 below shows a mixed filter layer (3GB) using a mixed filter slurry containing 9 wt% of a blue pigment and 1 wt% of a green pigment on the inner surface of the panel 1 on which the black matrix 2 is formed, and a rust phosphor on the upper surface thereof. After forming the layer 4G, the blue phosphor layer 4B without the pigment, and the red phosphor layer 4R with the large amount of the red pigment 7, the cathode ray tube was formed, and then the outer surface of the panel 1 was formed. The colored coating layer 6 was formed (Example 1), and the color cathode ray tube (prior art 1) to which the fluorescent substance with a pigment was conventionally applied was compared with the color cathode ray tube (prior art 2) in which only the blue filter layer was formed.

TABLE 2

Conventional product 1 Conventional product 2 Example 1 Color reproducibility 100 107 110 Luminance 100 112 118 Contrast Ratio 100 100 100

As shown in Table 1, the fluorescent film according to the present invention can be seen that the luminance is improved by about 18% based on the same contrast ratio, and the color reproducibility is increased by 10% or more compared to the conventional, which results in a screen having excellent color purity. It can be seen that it can be implemented.

Although described above is a specific embodiment according to the present invention, it is obvious that the present invention may be variously modified and implemented by those skilled in the art.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

According to the present invention, it is clear from the above description that the contrast property is improved by the red phosphor layer and the mixed filter layer containing a large amount of pigment, and the color purity characteristic is improved as the dominant wavelength region of green emission color is moved to the short wavelength region by the mixed filter layer. In addition, it is possible to implement the improvement of the luminance characteristics by using a phosphor that does not have a pigment attached, it is possible to simplify the process to reduce the manufacturing cost and productivity.

Claims (14)

In a fluorescent film of a color cathode ray tube, a black matrix, which is an external light absorbing layer, is formed on an upper surface of a panel having a predetermined light transmittance, and a phosphor layer of red, green, and blue, which is a light emitting pixel, is formed on an upper surface of the panel on which the black matrix is formed: (1) the red phosphor layer comprises a red phosphor having red pigment of fine particles attached thereto; (2) at least one of red and green and blue are mixed between the blue phosphor layer and the panel and between the green phosphor layer and the panel such that the light transmittance at wavelengths of 450 nm and 535 nm is 60% or more; A fluorescent film structure of a color cathode ray tube, characterized in that two or more mixed filter layers are formed. The method of claim 1, The red phosphor is attached to the red pigment 1wt% or more of the fluorescent film structure of a color cathode ray tube. The method of claim 1, The panel has a light transmittance of 40 to 85% of the fluorescent film structure of a color cathode ray tube. The method of claim 3, wherein The light transmittance of the panel is 40 to 60%; The outer surface of the panel is a fluorescent film structure of a color cathode ray tube, characterized in that the outer coating film (film film) is formed is not reduced light transmittance. The method of claim 3, wherein The light transmittance of the panel is 60 to 85%; The outer surface of the panel is a fluorescent film structure of a color cathode ray tube, characterized in that a colored coating film (film film) containing a color pigment for reducing light transmittance is formed. In a method of forming a fluorescent film of a color cathode ray tube in which a black matrix as an external light absorbing layer, a filter layer having light selective transmission characteristics, and a phosphor layer constituting pixels are sequentially formed on an inner surface of a panel having a predetermined light transmittance: (1) A mixed filter slurry liquid containing a mixed pigment dispersion liquid obtained by dispersing at least one of a predetermined red pigment and a green pigment and a predetermined blue pigment is applied to the green and blue positions on the inner surface of the panel and exposed and developed to form a mixed filter layer. Forming a; (2) forming a red phosphor layer using a red phosphor having a predetermined red pigment attached thereto; And (3) A method of forming a fluorescent film of a color cathode ray tube, comprising alternately forming a blue phosphor layer and a green phosphor layer on an upper surface of the mixed filter layer. The method of claim 6, The red pigment comprises iron oxide (Fe ₂ O ₃ ); The green pigment comprises cobalt green (ZnO—TiO ₂ —NiO—CoO); The blue pigment comprises a cobalt blue (CoO-Al ₂ O ₃ ) It characterized in that the fluorescent film forming method of the color cathode ray tube. The method of claim 6, As the red pigment attached to the red phosphor, those having a particle diameter of 200 nm or less are used; Each pigment to be added to the mixed pigment dispersion is a fluorescent film forming method of the color cathode ray tube, characterized in that the particle size of 100nm or less. The method of claim 6, The method of forming a fluorescent film of a color cathode ray tube, characterized in that the red pigment is attached to the red pigment by 1wt% or more. The method of claim 6, The method of forming a fluorescent film of a color cathode ray tube, characterized in that each pigment is added to the mixed pigment dispersion in a content ratio of 5 to 20 wt%. The method of claim 6 or 10, The method of forming a fluorescent film of a color cathode ray tube, characterized in that when the pigment is added to the mixed pigment dispersion in a content ratio of 5wt% or less, blue pigment is attached to the blue phosphor that forms the blue phosphor layer at 1wt% or less. The method of claim 6, And a panel having a light transmittance of 40 to 85% as the panel. The method of claim 12, The panel having a light transmittance of 40 to 60%; A method of forming a fluorescent film of a color cathode ray tube, characterized in that to form an outer coating film (film film) on the outer surface of the panel which does not cause a decrease in light transmittance. The method of claim 12, The panel having a light transmittance of 60 to 85%; A method of forming a fluorescent film of a color cathode ray tube, characterized in that the outer surface of the panel to form a colored coating film (film film) containing a color pigment for reducing the light transmittance.