JPS61284035A - Fluorescent screen of cathode-ray tube for color display - Google Patents

Abstract

PURPOSE:To improve brightness, by forming a phosphor layer in two layers structure, and forming a phosphor layer common to the three color dots in the first layer and a phosphor layer with different color tones of three colors in the second layer. CONSTITUTION:The first phosphor layer 3 common to the three color phosphor dots is formed over the surface of a panel 1, over which, blue, green, and red phosphor dots 4 to 6 are formed. In this case, 2 in the figure is a black matrix and 7 is an aluminum layer. Since a phosphor layer is formed in the first layer to make the inner surface of the panel uneven, and three color phosphor dot patterns are formed thereover, strength of adhesion is so large that drops of phosphor dots can be prevented, even though an optimum membrane thickness is applied to get a maximum brightness. Furthermore, since the phosphor layer in the first layer is common to three colors, the screen can be formed with no shado mask.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluorescent surface of a cathode ray tube for a three-color color display.

[Conventional technology]

Conventionally, three-color phosphor dots of green, blue, and red have been formed on the phosphor surface of a three-color color display housing cathode ray tube using a slurry method similar to the manufacturing method of commercial television cathode ray tubes. That is, first, on a panel on which a black matrix was formed, an excess amount of slurry IJ-, in which an edge wall light material was suspended in a mixed solution of polyvinylfluorcol (PVA) and 11L ammonium chromate (ADC), was placed with the inner surface of the panel facing upward. The coating is applied, the slurry is shaken off with high speed rotation, the slurry is dried using an infrared heater and a blower, a shadow mask is attached, exposure is performed using a high-pressure mercury lamp, and the edge wall light dot pattern is formed by developing with warm water. Next, the slurry of the front wall light material suspended in a mixed solution of PVAADC is coated with the slurry, shaken off, dried, exposed, and developed in the same manner as in the case of the green phosphor material to form the entire blue light material dot pattern. A red phosphor dot pattern was formed in exactly the same manner.

[Problem that the invention seeks to solve]

When forming phosphor dot patterns for high-resolution tubes or ultra-high resolution tubes with small holes in the shadow mask using this method, the adhesion strength of the phosphor dots to the panel surface becomes weak, so the phosphor dots may be removed during development. The phosphor dots are likely to be missing, and therefore the phosphor film thickness has to be made smaller than the optimal film thickness that maximizes brightness. Therefore, there was a drawback that the luminous efficiency of the fluorescent surface was lowered and the brightness was lowered. [Means for solving the problem] The present invention uses a slurry method to improve the luminous efficiency of the fluorescent surface of high resolution tubes and ultra-high resolution. The objective is to provide a maximum fluorescent surface.

That is, as shown in the fourteenth sectional view, first, a first phosphor layer 3 common to three color phosphor dots is formed on the surface of the panel 1.
on which blue, green, and red phosphor dots 4, 5 .
6? It has a formed structure. Note that 2 is a black matrix and 7 is aluminum. A phosphor layer is formed on the first layer to make the inner surface of the panel uneven, and a three-color phosphor dot pattern is formed on top of it, so the adhesive strength is strong and even when the optimal film thickness is used to maximize brightness. It is possible to completely prevent the loss of fluorescent dots. Further, since the first phosphor layer has three colors in common, it can be formed without attaching a shadow mask, so the increase in the number of steps does not complicate production. The three emission colors can be obtained by reducing the thickness of the phosphor in the first layer and increasing the thickness of the phosphor in the second layer, and changing the emission color of the phosphor in the second layer as necessary. The required luminescent color can be obtained by making all the adjustments.0 [Example] Using a 14-inch shadow mask hole pitch of 0.251 m, after fully forming the black matrix, the average particle size was 6.0 microns. Copper gold aluminum activated zinc sulfide phosphor (Zn
S: CuAuAt) 40%, silver-activated zinc sulfide phosphor (ZnS: ) with an average particle size of 6.0 microns, ? )3
Europium-activated yttrium oxysulfide (YtOx S:Eu) with 0%, average particle size of 5.5 microns 30
% of mixed phosphor was suspended in a mixed solution of PVA and ADC.

After coating with a slurry specific gravity of 1,110 and viscosity of 33 CPS and drying, the entire inner surface of the panel is illuminated with a high-pressure mercury lamp without a shadow mask and developed with hot water to form a first phosphor layer pattern. The film thickness of this phosphor layer is L Om t/
It was "car".

Next, ZnS: CuAuA with an average particle size of 8.0 microns
The L phosphor was suspended in a solution of ePVA and ADC, and the specific gravity was 1.
270. Coat with viscous IJ [35 CPS, dry, expose with a shadow mask, and develop to form an edge wall photon dot pattern. and Zns with average particle size &5 microy
: AP fluorescer is suspended in a solution of PVA and ADC,
A front wall light dot pattern is formed by coating with a specific gravity of 1.270 and a viscosity of 38 CPS in the same manner as the edge wall light dot pattern. And average particle size &0 micron Y, Q, S:
Eu phosphor was suspended in a solution of PVA and ADC, and the specific gravity was 1.
．． 270. A red phosphor dot pattern is formed in the same manner as the edge wall phosphor dot pattern by coating at a viscosity of 42 CPS. The phosphor film thickness is green, including the first phosphor layer.
It was 3.8 m f/cm in the blue phosphor layer and 4.21'l'l f/cm in the red phosphor layer.

The color of the emitted light is CIE chromaticity as shown in Figure 2, and green is!
=0.300, y=Q,! 5so, blue is x=0.155
, y=Q, Q75. Red is X: 0.600%y=o, 3s
It was o. Compared to the chromaticity currently generally used, green, blue, and red all had a slightly whiter color tone, and there were no problems in use. The brightness of green, blue, and red has been improved by 15% compared to the conventional model.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to prevent the phosphor dots from being missing without making the manufacturing method too complicated, so the total thickness of the phosphor film can be increased, and the overall brightness is much higher than that of the conventional method. It can be improved by 15%. Therefore, it is very useful in practice for creating a high-resolution fluorescent surface.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the fluorescent surface of the present invention, and Fig. 2 is a chromaticity diagram of an embodiment of the present invention. ...First phosphor layer, 4... Front wall dots, 5... Edge wall light dots, 6...
...-red phosphor dot, 7...aluminum. Agent Patent Attorney Susumu Uchihara
・'□, 7. ';\-9ko'+1 Title・

Claims (1)

[Claims] On the phosphor surface of a three-color display tube that emits light when stimulated by cathode rays, the phosphor layer has a two-layer structure, with the phosphor layer common to three-color dots formed in the first layer, and the A phosphor surface of a cathode ray tube for a color display, characterized in that phosphor layers of different tones are formed.