KR100428969B1 - Cathode ray tube screen film adopting black filter film formed on glass panel - Google Patents

Abstract

PURPOSE: A cathode ray tube screen film is provided to prevent degradation of contrast while maintaining high luminance even when a glass panel of high transmissivity is used. CONSTITUTION: A cathode ray tube screen film comprises a glass panel(210); a black matrix pattern(220) formed on the glass panel; a black filter film(230) formed in a non-black matrix portion on the glass panel; and a phosphor film formed on the black filter film, wherein the phosphor film includes a red phosphor(240), a green phosphor(250), and a blue phosphor(260) arranged thereon. The black filter film is formed from a black filter forming composition containing Ti-containing black pigment material.

Description

Cathode ray tube screen membrane with black filter membrane

The present invention relates to a cathode ray tube screen membrane employing a black filter membrane, and more particularly, to a cathode ray tube screen membrane capable of preventing a decrease in contrast while using a glass panel with high transmittance by employing a black filter membrane.

In general, green, blue and red light emitting phosphor patterns are regularly arranged in the form of dots or stripes in the color cathode ray tube screen film, and a black matrix is formed between the phosphor patterns to improve contrast and color purity of the screen film. . When electrons are irradiated from the electron gun on such a screen film, the phosphor emits light and the required image is realized.

This conventional colored cathode ray tube screen membrane is shown in FIG.

That is, the black matrix pattern 120 is formed on the glass panel 110, and the fluorescent film to which the red, green, and blue phosphors 140, 150, and 160 were respectively applied is formed between the black matrix patterns.

However, one of the conditions required for realizing high quality image quality is that the flicker phenomenon should not occur. In order to remove the flicker phenomenon, a method of using a long afterglow phosphor has been proposed. However, the long afterglow phosphor has a problem that the luminance is significantly lower than that of the general ZnS phosphor. In particular, in the case of the green phosphor, the luminance decrease is serious.

As a method of overcoming the decrease in luminance, a method of using a glass panel having high transmittance may be considered.

Generally, glass panels that can be used for cathode ray tubes are classified according to transmittances, such as dark-tint glass panels having a transmittance of 40-50%, semi-tint glass panels having 50-60%, and It can be roughly classified into a clear-tint glass panel of 80-90%, and the brightness and contrast characteristics of the cathode ray tube screen film vary depending on the type of glass panel employed.

In more detail, when the dark tint glass panel is used, the external light is absorbed by the glass panel, and the contrast is improved. However, since the light excited by the phosphor is also absorbed by the glass, the luminance is lowered. On the contrary, in the case of using the clear tinted glass panel, since the light excited by the phosphor mostly passes through the glass, the brightness is high, but the contrast is lowered because external light is not absorbed by the panel.

That is, the brightness and contrast characteristics are inversely proportional to the transmittance of the glass panel used.

Therefore, when using a glass panel with high transmittance in order to improve the brightness, there is a problem in that a significant reduction in contrast is to be taken.

The technical problem to be achieved by the present invention is to provide a cathode ray tube screen membrane that can prevent the degradation of the contrast while increasing the brightness of the screen membrane by using a glass panel with high transmittance.

1 is a cross-sectional view of a conventional cathode ray tube screen surface.

2 is a cross-sectional view of the cathode ray tube screen surface according to the present invention.

* Description of the symbols for the main parts of the drawings *

110, 210 ... glass panel 120, 220 ... black matrix pattern

140, 240 ... red phosphor 150, 250 ... green phosphor

160, 260 ... blue phosphor 230 ... black filter membrane

Technical problem of the present invention is a glass panel; A black matrix formed on the glass panel; A black filter film formed on the black matrix unformed portion on the glass panel; And a screen film of a cathode ray tube including a fluorescent film formed by arranging red, green, and blue phosphors on the black filter film.

The black filter film is formed from a composition for forming a black filter containing a Ti-containing black pigment material.

At this time, the particle size of the Ti-containing black pigment material is preferably 1 μm or less, more preferably 50-150 nm.

In addition, the phosphor of the fluorescent film is not particularly limited as long as it can be used in the field of the present invention, preferably Y ₂ O ₂ S: Eu as a red phosphor, ZnS: Cu, Au, Al or long afterglow phosphor as a green phosphor Examples of the mixed phosphor of phosphorus ZnS and InBO ₃ : Tb and the blue phosphor include ZnS: Ag and Cl.

On the other hand, the glass panel used is preferably semi tint or clear tint.

Hereinafter, with reference to the drawings will be described in detail the principle of the present invention and a method for producing a cathode ray tube screen film.

2 is a cross-sectional view showing a screen film of a cathode ray tube according to the present invention.

First, a black matrix pattern 220 is formed on the glass panel 210. Subsequently, a black filter film 230 is coated on the glass panel on which the black matrix is not formed, and then red, green, and blue phosphors 240, 250, and 260 are coated on the black filter film to form a fluorescent film. .

At this time, as a method for producing the black matrix and the fluorescent film, a conventional method is used. In addition, in the case of a black filter film, the composition for forming a black filter in which the Ti-containing black pigment material is dissolved in a solvent together with a binder, a surfactant, a photosensitive agent, and a dispersant is applied to a black matrix unformed part on a glass panel, and then cured and dried. Can be prepared.

Herein, the Ti-containing black pigment material is fine particles having a thickness of preferably 1 μm or less, more preferably 50-150 nm, as described above, and when the particle size is out of the above range, the light transmittance of the panel is remarkably decreased. .

As mentioned above, the principle of the present invention is that the black filter film compensates for the lowering of contrast that may be caused by using a glass panel having a higher transmittance than the glass panel used in general. Therefore, it is to obtain a screen film having good brightness and contrast.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example

After forming a black matrix pattern on the clear tinted glass panel, a black filter film-forming composition having the following composition was applied to the black matrix pattern unformed portion, and then dried and cured to form a black filter film:

100 g of water

Black pigment material (TILACK: Asahi chemical product) 3g

Polyvinyl Alcohol 8g

10 g of surfactant (polyethylene sodium sulfonate)

Photosensitizer (sodium dichromate) 8g

Dispersant (diethylene glycol) 8 g

Subsequently, a fluorescent film was formed on the black filter film using a mixed phosphor of Y ₂ O ₂ S: Eu as a red phosphor, ZnS: Ag, Cl as a blue phosphor, and ZnS and InBO ₃ : Tb as a green phosphor.

The brightness and contrast of the screen film prepared as described above were measured and visually observed whether a flicker phenomenon appeared, and the results are shown in Table 1 below.

Comparative example

A cathode ray tube screen film was formed in the same manner as in the above embodiment except that a semi-tint glass panel was used and no black filter film was formed.

The brightness and contrast of the screen film thus prepared were measured, and the degree of improvement of the flicker phenomenon was observed, and is shown in Table 1 below.

Table 1

Transmittance of glass panel Luminance Contrast Flicker phenomenon Example 62% 100% 100% Improved Comparative example 56% 100% 100% Severe

The results of Table 1 show that the screen membrane of the present invention has excellent contrast even when a glass panel having high transmittance is used by employing a black filter membrane, and particularly, when the long afterglow phosphor is used as a green phosphor, the flicker phenomenon is improved. .

The screen film of the cathode ray tube according to the present invention has the advantage that the contrast can be prevented while maintaining the effect of greatly improving the luminance even when a glass panel having a high transmittance is used. In particular, in the case of a cathode ray tube screen film using a long afterglow phosphor, various effects of providing high brightness and high contrast as well as removing flicker may be simultaneously obtained.

Claims (4)

Glass panels; A black matrix formed on the glass panel; A black filter film formed on the black matrix unformed portion on the glass panel; And A screen film of a cathode ray tube including a fluorescent film in which red, green and blue phosphors are arranged on the black filter film. The screen film of a cathode ray tube according to claim 1, wherein the black filter film is formed from a composition for forming a black filter comprising a Ti-containing black pigment material. The cathode ray tube screen membrane of claim 2, wherein the Ti-containing black pigment material has a particle size of 1 μm or less. The cathode ray tube screen film according to claim 1, wherein the green phosphor is a long afterglow phosphor.

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