KR19980017590A - Method for manufacturing fluorescent surface of color brown tube - Google Patents

Abstract

The present invention discloses a novel method for producing fluorescent surfaces of color brown tubes.

Conventionally, since the fluorescent surface was manufactured by photolithography, it was difficult to maintain a clean state because it was a complicated process and a wet process, and there were various problems such as the metal bag being lifted because the fluorescent layer was uneven.

In the present invention, a printing mask is formed by a photolithography method and each phosphor is printed and then fired to produce a fluorescent surface, thereby making it possible to produce a stable color brown tube of high quality by a simple dry process.

Description

Method for manufacturing fluorescent surface of color brown tube

1 (a) to (h) are sequential cross-sectional views showing a conventional fluorescent surface manufacturing method,

2 is a cross-sectional view of a panel showing the method of the present invention,

3 is a cross-sectional view showing the manufacturing process of the printing mask to be used in the method of the present invention,

4 is a flow chart of the method of the present invention,

5 is a cross-sectional view of the fluorescent surface produced by the present invention.

* Explanation of symbols used in the main part of the drawing *

P: Panel

R, G, B: phosphor

BM: black matrix

MB: metal back

M: print mask

SM: shadow mask

T: Paste

The present invention relates to the production of color-brown tubes, and more particularly to a method for producing the fluorescent surface.

Black and white brown tubes, which form fluorescent surfaces with a single phosphor, can be produced simply by precipitation or spin coating.However, in color brown tubes, R, G, and B phosphors are interposed between black matrices. Since the pattern must be formed of a repeating pattern of dots or stripes, a high precision fine patterning process is required.

The micro patterning method that has been generally used for the production of such color fluorescent surface is photo lithography, which will be described with reference to FIG. 1.

First, as shown in (a) of FIG. 1, a predetermined amount of a slurry of one of the black matrix or any one of R, G and B phosphors is injected into the inner surface of the panel (P): (b) and As described above, the coating film L is formed by rotating the panel P to disperse the slurry S by centrifugal force.

When the excess slurry (L) is removed and drying of the coating film (L) is completed, a shadow mask (SM) is mounted on the panel (P) as an exposure mask as shown in (c) to select the coating film (L) through it. When the exposure film is exposed to light, and the coating film L is developed with washing water or the like as shown in (d), the inner surface of the panel P has a black matrix or a pattern N of any one of R, G and B phosphors as shown in (e). Is formed.

By repeating this process four times to form each phosphor R, G, and B in a predetermined pattern between the black matrix BM, a metal back (MB) is formed on the upper surface thereof. Since the back surface of R, G, and B) is not uniform, and the mirror surface of the metal back MB is difficult to be formed, as shown in (f), the upper surfaces of the phosphors R, G, and B are combustible. The intermediate layer 1 is formed of an organic material or the like.

Then, as shown in (g), the metal back (MB) is formed by evaporation of A1 or the like on the intermediate layer (I), and then the intermediate layer (I) is heated and removed by thermal decomposition as shown in (h) to complete the fluorescent surface. Done.

Thus, the conventional color fluorescent surface manufacturing process is not only a complicated process consisting of a very multi-step, but also a wet process using a slurry (S) itself, so even after repeated washing several times in each step, high clean state It is difficult to implement a high-precision color CRT manufacturing environment, which requires a high degree of contamination of the peripheral device and the environment.

In addition, when the fluorescent surface is manufactured by exposure using the shadow mask SM as an exposure mask, the complicated path of the electron beam cannot be accurately reproduced by the exposure light source, and thus there is a problem that the image quality of the periphery of the CRT is greatly reduced. Exposing and developing four times per day to form a high-resolution fluorescent screen requires a lot of manpower and skill, but does not guarantee uniform CRT quality.

In addition, since fine pores are formed in the metal back MB to exhaust combustion gas generated during thermal decomposition of the intermediate layer I, it is difficult to obtain a complete mirror surface, and in this process, the metal back MB is lifted off from the fluorescent surface. Or application of a high voltage for acceleration of the electron beam will cause problems of local instability.

In view of such a conventional problem, an object of the present invention is to provide a method for producing a color-brown tube that is simple in process, clean and stable in quality even in mass production, and obtains a uniform fluorescent surface.

In order to achieve the above object, the present invention has a basic characteristic of forming a fluorescent surface by a printing method, which is a dry method. Each phosphor is composed of a printing paste mixed with a low melting glass powder and printed. After printing through a mask, it is calcined to form a hard fluorescent surface.

Such specific features and other advantages of the method of the present invention will become more apparent from the following description of the preferred embodiments with reference to the accompanying drawings.

In FIG. 2, the printing paste of the phosphor is formed on the inner surface of the panel P through the printing mask M formed between the opaque layer X and the transmissive window A in a shape corresponding to the required pattern N of the phosphor. T) is printed to form a pattern N of the black mattress BM or the phosphors R, G, and B.

Here, the printing paste (T) of the phosphor is preferably a composition in which a black matrix (BM) or low-melting glass powder is mixed with each phosphor (R, G, B) and suspended in a volatile binder, and dried. When the binder is volatilized and heated, a low melting glass powder is prescribed, and a black matrix (BM) or phosphor (R, G, B) dot or stripe of the corresponding shape is placed at the pattern (N) position. To form.

Here, four printing masks (M) are required for the black matrix (BM) and three phosphors (R, G, and B), and are preferably manufactured in the same manner as in FIG.

The impermeable layer (X) material is applied to the printing mask (M) together with the photosensitive material and is installed on the support plate (10) in a state where a coating film is formed. A bracket 20 is installed outside the support plate 10 to support a shadow mask SM with a studpin 30 provided therein.

In this state, when the coating film of the printing mask M is selectively exposed using the shadow mask SM as an exposure mask, and then developed, the transparent layer A having a predetermined pattern is formed between the impermeable layer X, thereby printing the mask. M) is configured.

In this case, the positions of the black matrix BM and the transmission window A to form the pattern N of the phosphors R, G, and B are different from each other, so that the exposure light is shifted by a wedge lens or the like. (shifting) to configure each print mask (M).

The manufacturing process of such a printing mask (M) is substantially the same as the conventional photolithography method of the conventional fluorescent surface described with reference to Figure 1, the printing mask (M) of the present invention is manufactured in one photo-etching method after its durability Therefore, since it may be repeatedly used in at least several hundred panels P, it is greatly different from the conventional method of manufacturing each fluorescent substance panel by exposing each panel P daily.

That is, in FIG. 3, the shadow mask SM does not correspond 1: 1 to each panel P as in the related art, but becomes a master mask and prints a plurality of panels P that can be printed with the printing mask M. FIG. ) Will become the original.

On the other hand, the panel P is composed of optical glass, and the inner surface thereof becomes a smooth glass surface, which may cause poor adhesion of the printing paste T to the panel N. This problem may be solved by a method including a large amount of glass powder in the printing paste T or the addition of other additives. However, in order not to affect the composition of the fluorescent layer, an adhesion layer H may be formed on the inner surface of the panel P in advance. Is preferred.

The adhesion layer H may be formed of a paste in which powder such as SiO ₂ is suspended, and may be formed on the inner surface of the panel P by spraying, rotating coating, or printing, and the panel P may be phosphor in a dry state. It is possible to improve the adhesion with the pattern (N) and to be fired together when firing the pattern (N).

The overall flow of the method of the present invention is illustrated in FIG. 4, and after forming the adhesion layer H on the inner surface of the panel P in step 100, the black matrix BM is printed in step 110. do. Black matrix (BM) is usually based on graphite, and since graphite has good adhesion to glass, it is possible to form black matrix (BM) without mixing or sintering glass-based powder. In order to form (MB) into a flat mirror surface, the black matrix (BM) and the phosphors (R, G, B) are preferably formed with the same thickness, so the black matrix (BM) is also printed by mixing with a low melting glass powder. The paste T is formed and printed through the printing mask M, and then dried and calcined in step 120. By the firing of the black matrix BM, the adhesion layer H at the bottom thereof may also be baked.

Then, the phosphors R, G, and B are sequentially printed (step 130), dried, and fired (step 140) between the black matrices BM.

After the fluorescent layer is formed, a metal back (MB) is formed on the back side (step 150). Each phosphor (R, G, B) and the black matrix (BM) are formed by printing and firing, and thus have a uniform thickness. It can be formed as.

Accordingly, the metal back MB can be formed by directly depositing A1 or the like on the fluorescent layer without forming the intermediate layer (I in FIG. 1). As a result, the fluorescent surface as shown in FIG. 5 is completed on the inner surface of the panel P. As shown in FIG.

Comparing the fluorescent surface of the present invention of FIG. 5 with the conventional fluorescent surface of FIG. 1 (h), the fluorescent layer composed of the black matrix BM and the phosphors R, G, and B is formed in a very uniform state, and the metal back It is possible to apply a uniform acceleration potential by being in close contact between the MB and the fluorescent layer without being lifted, thereby realizing a high-quality high brightness image.

In addition, since there is no formation of the intermediate layer (I) or the thermal decomposition process, the metal back (MB) forms a very uniform mirror surface without pores.

In addition, there is no wet process using slurry (S) or washing water to form a fluorescent surface, and thus it is possible to manufacture a color brown tube in a high clean state without surrounding contamination.

As described above, according to the present invention, it is possible to provide a color-brown tube having a stable characteristic of high quality at a low cost in a simple dry process.

Claims (5)

In the manufacturing method of the formation surface of the color-brown tube which forms a black matrix and each phosphor of R, G, B in a predetermined pattern on the inner surface of a panel, Each of the black matrix and the phosphors was formed as a printing paste including low melting glass powder, After each printing paste is printed in a pattern on the inner surface of the pattern through a printing mask, Forming a fluorescent surface by firing the printed pattern to form a fluorescent surface of the color brown tube. The method of claim 1, Forming an adhesion layer on the inner surface of the panel, and then printing each of the printing paste on the adhesion layer characterized in that the fluorescent surface manufacturing method of the color brown tube. The method of claim 2, Method for producing a fluorescent surface of a color brown tube, characterized in that the adhesive layer is composed of a paste containing a SiO ₂ powder. The method of claim 1, And the printing mask is manufactured by photolithography using the shadow mask of the color brown tube as an exposure mask. The method of claim 1, The black matrix and the printed pattern of each phosphor are formed to have the same thickness, and a metal back is formed by depositing A1 on the upper surface thereof.