JPS62249331A - Manufacuture of phosphor screen - Google Patents

Abstract

PURPOSE:To prevent a blister generated on a metal evaporation film and to improve the brightness in the phosphor screen by adhering inorganic fine grain onto the portion where a light absorbing material not covered with phosphors prior to the formation of an organic film. CONSTITUTION:Three kinds of phosphors with respective luminescent colors of red R, green G and blue B are formed and thereafter inorganic fine grain 8 is adhered onto the portion where light absorbing materials not covered with phosphors are exposed. Then, an organic film 5 is formed thereto so as to smooth the backing of the phosphor screen and further a metal evaporation film 6 is formed on the organic film 5. Since the inorganic fine grain 8 is located only on the backing of the light absorbing materials 4, pitting are prevent on the metal evaporation film 6 located on the backing of the phosphor, thereby the metal evaporation film 6 is effectively functioned as the backing reflecting mirror Therefore, it is possible to prevent a blister and improve the brightness of the phosphor screen.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a fluorescent screen, and in particular, the phosphor is surrounded by a black light-absorbing material. The present invention relates to a method for manufacturing a so-called black matrix type fluorescent screen.

[Prior Art] FIG. 3 is a diagram showing a conventional fluorescent screen manufacturing method in the order of steps. First, washed n1 panel glass (1)
A photoresist (2) containing polyvinyl alcohol and ammonium chromate as main components is applied onto the inner surface of the substrate (see FIG. 3(a)).

Next, the photoresist (2) is dried, a shadow mask (not shown) is attached, and a phosphor is to be formed at a position 21 (g) from three predetermined light source positions through the shadow mask. ), (b), and (r),
Remove the unexposed area (3) by applying water to remove the unexposed area (3).
b)), and then a suspension of black light-absorbing material (4) such as graphite or carbon black is applied thereon and dried (see Fig. 3(c)).

Next, an aqueous solution of harsh chemicals such as hydrogen peroxide and periodate is added over the remaining photoresist (2).
Oxidize and solubilize, wash with water, and make photoresist (2
) to form a black matrix (10) (see FIG. 3(d)).

Furthermore, a red light emitting phosphor (R
), green-emitting phosphor (G), W-color emitting phosphor (B)
are formed in a regular array on the inner surface of the panel glass (1) (see FIG. 3(e)).

Next, a methyl methacrylate resin emulsion (emulsion) is applied and heated to destroy the emulsion and form an organic skin v (5) to smooth the fluorescent screen (so-called filming). Figure 3 (see Figure 3 () 8), and then evaporate aluminum from above to form a gold-deposited M film (6) to complete the fluorescent screen (20) (Figure 3 (g)). reference).

[Problems to be Solved by the Invention] In the fluorescent screen (20) manufactured by the conventional method described above, the 71-layer film ( 5) is caused by the gas generated by decomposition.

As shown in Figure 4, the blister (7) is fully retracted and the 8-diaphragm (6)
) and become a stain on the fluorescent screen (2o).

So, to prevent this blistering (7).

Holes are made in the metal evaporator film (8) to facilitate the escape of decomposition gas from the organic film (5). This metal vapor deposited film (6
Conventionally, as shown in Fig. 5, inorganic fine particles (9) are added to the filming material and made to exist uniformly in the organic film (5), as shown in Fig. 6, or as shown in Fig. 6. A method has been used in which after the completion of the organic film (5), inorganic fine particles (8) are spray-coated to deposit the inorganic fine particles (3) on the entire back surface of the organic film (5).

However, in such a method, the phosphor (R)
, (G), and (B), there are also holes in the metal vapor deposited film (8) located on the back surface, so that all four vapor deposited films (8) cannot sufficiently fulfill the role of the back reflector.

There was a problem in that the brightness of the fluorescent screen (20) was significantly reduced.

This invention has been made to solve the above problems, and aims to provide a new manufacturing method that can not only prevent blisters that occur on metal vapor deposited films, but also improve the brightness of fluorescent screens. The purpose is

[Means for Solving the Problems] In the method for manufacturing a fluorescent screen according to the present invention, prior to forming an organic film for smoothing the back surface of the phosphor, a light-absorbing material that is not covered with the phosphor is It is characterized by having inorganic fine particles near the exposed part.

[Function] In the method of the present invention, since the inorganic fine particles are localized only on the back surface of the light-absorbing material, there are no holes in the metal vapor deposited film located on the back surface of the phosphor. Since the film can fully perform its function as a back reflector, the reflection efficiency is high and there is almost no reduction in the brightness of the fluorescent screen. Since it escapes from the part of the metal 77 deposited film that has many holes, no blisters occur.

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

FIG. 1 is a process diagram showing an embodiment of the method for manufacturing a fluorescent screen according to the present invention. The same parts as in FIG. 3 are given the same reference numerals. First, as shown in FIG. 1(a), a black matrix (lO) made of a light-absorbing substance (4) is formed on a panel glass (1). The steps to form this black matrix (lO) are shown in Figures 3(a) to (d).
), so it is omitted here.

Next, a red light-emitting phosphor (R
), a green-emitting phosphor (G), and an old-color emitting phosphor (B) are arranged regularly on the inner surface of the panel glass (1) (see FIG. 1(b)).

Next, three color phosphors (R), (G), (
The panel glass (1) on which B) was formed was immersed in a 1% isopropyl alcohol solution of aluminum nitrate in which colloidal silica (trade name "Ludotux") was decomposed, and then the light-absorbing glass made of graphite was immersed. Using substance (4) as a negative electrode, positively charged colloidal silica (8) was heated to phosphor (R) and C under conditions of 100V and 20mA.
G), a light-absorbing material not covered with (B)* (
4) was electrodeposited on the exposed portion (see FIG. 1(C)). The time required for this electrodeposition was 10 minutes.

Next, a methyl methacrylate resin emulsion (emulsion) containing no inorganic particles is applied and heated to destroy the emulsion.・Filming to form an organic film (5) and smooth the fluorescent screen. (See Figure 1(d)).

After that, aluminum is deposited on top of it, resulting in a fluorescent screen (8) in which a metal deposited film (8) with holes formed only on the back side of the light-absorbing substance (1O) where colloidal silica (8) is localized. 20) is completed (Fig. 1(e)
reference).

A partially enlarged sectional view of the fluorescent screen (20) manufactured in this manner is shown in FIG.
0), each phosphor (R), (G),
There were no holes or cracks in the metal vapor deposited film (6) on the part facing the back side of (B), and when we measured the brightness after the color picture tube was completed, we found that it had a colloidal appearance of 2% compared to the conventional one. It was about 20% brighter than a fluorescent screen made by a filming method using an emulsion containing silica. Moreover, no blistering occurred at all even during the baking process after the formation of the metal deposited film (8).

In the above example, colloidal silica (8) was used as the inorganic fine particles, but any inorganic fine particles such as colloidal alumina, titanium oxide, zinc oxide, etc. may be used.
Further, although methyl methacrylate emulsion was used as the filming material, other emulsions such as methyl methacrylate emulsion, or even lacquers other than emulsions may be used, and the same effects as in the above embodiments can be obtained.

[Effects of the Invention] As described above, according to the present invention, inorganic fine particles used for the purpose of preventing blisters are attached only to the back surface of the light-absorbing material, which has no relation to the brightness or brightness of the fluorescent screen. This has the effect of preventing blisters and significantly improving the brightness of the fluorescent screen.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing a method for manufacturing a fluorescent screen according to an embodiment of the present invention, FIG. 2 is a partially enlarged sectional view of a fluorescent screen manufactured by the method shown in FIG. 1, and FIG. 3 is a conventional fluorescent screen. 4 to 6 are cross-sectional views of fluorescent screens manufactured by the conventional method. (1)...Panel glass, (4)...Light-absorbing material, (5)...Organic film, (B)...Metal deposited film, (
8) Colloidal silica (inorganic fine particles), (
10)... Black matrix, (20)... Fluorescent screen, (R)... Red light emitting phosphor, CG)...
- Green-emitting phosphor, (B)...Blue-emitting phosphor. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (3)

[Claims] (1) Three types of phosphors emitting red, green, and blue colors were regularly arranged on the inner surface of the panel glass, and a black matrix made of a black light-absorbing material was formed between each phosphor. In the method for manufacturing a fluorescent screen, after the phosphor is formed, inorganic fine particles are attached to the exposed portion of the light-absorbing material that is not covered with the phosphor, and then organic fine particles are attached to the exposed portion of the light-absorbing material that is not covered with the phosphor, and then an organic particle is attached to the exposed part of the light-absorbing material that is not covered with the phosphor. A method for manufacturing a fluorescent screen, comprising forming a film and also forming a metal vapor deposited film on the organic film. (2) A method for manufacturing a fluorescent screen according to claim 1, wherein the inorganic fine particles are deposited by electrodeposition using a light-absorbing substance as a counter electrode. (3) The method for manufacturing a fluorescent screen according to claim 1 or 2, wherein the inorganic fine particles are colloidal silica.