JPS601722A - Formation of color picture tube phosphor screen - Google Patents

Abstract

PURPOSE:To form a phosphor screen of good quality while evading the exfoliation of phosphor picture element in the developing process by performing development of a photosensitive slurry film after exposure, by means of ultrasonic wave. CONSTITUTION:A face panel 1 already subjected to an exposure process is mounted on the carrier 7 of a rotary applicator and dipped into the water in a water tank 9 provided with an ultrasonic wave oscillator 8, with the inner surface of the panel facing downwards. After development by exposing the phosphor screen to the ultrasonic wave for a certain time, said screen is pulled up from the water tank 9 for being washed out by running water while rotating the panel 1 at low speed of 10-20rpm. Thereby, the phosphor screen of good quality having no color mixture with other phosphor dots and no exfoliation of phosphor dots can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION A method for forming a fluorescent surface of a picture tube, particularly a method for developing, generally includes applying a photosensitive phosphor slurry 2 to the inner surface of a face panel 1 after cleaning, as shown in FIG. After drying, open the apertures 3 & 3 of the shadow mask 3 as shown in Figure 2.
A method is used in which the process of exposing to light from the light source 4 through the lens and then developing is repeated for each color. In Figure 3,
Defect-free fluorescent dots 5 formed in this way
An example of a dot-type fluorescent surface made of

Here, the above-mentioned developing process generally uses a hot water spray method in which hot water is sprayed from a nozzle 6 as shown in FIG. A phenomenon occurs. Figure 5 shows such a phosphor surface, with 5a in which the dots as phosphor pixels are completely missing, 5b in which the dots have slipped and returned to their original positions, and 5b in which the dots have been broken and are complete. There are cases such as 5c which do not form.

Therefore, in order to improve the adhesion of the dots and prevent such defects from occurring, the thickness of the film, the particle size of the phosphor,
Various optimal conditions are selected for the diameter of the light source, etc., but it is difficult to improve adhesive strength without impairing the film quality and brightness of the fluorescent surface. The invention of Shiraki, which uses adhesive strength in the formation of fine fluorescent surfaces, was made in view of this situation, and its purpose is to prevent the peeling of the phosphor pixels during the development process and to produce high-quality phosphor particles. In order to achieve this object, the present invention proposes a method for forming a color picture tube fluorescent light surface that can obtain a light surface. The face panel 1, which has undergone the exposure process in the same manner as before, is attached to the carrier 7 of a commonly used rotary coating machine, and with the inner surface of the panel facing downward, a water tank 9 equipped with an ultrasonic transmitter 8 is placed. immerse in water. After developing by applying ultrasonic waves to the fluorescent surface for a certain period of time, the panel 1 is removed from the water tank 9 and heated to 10 to 2 O as shown in FIG.
By rinsing with running water while rotating at a low speed of rpm, a high-quality phosphor surface was formed without color mixing with other color phosphor dots and without peeling of phosphor dots.

In this case, the diameter of the dots formed varies depending on the ultrasonic output and development time. FIG. 8 shows an example of experimental data showing the development time dependence of the dot diameter obtained by ultrasonic development on a light surface subjected to similar exposure. In this case, the frequency and power of the ultrasound transmitter used are 26 KHz and 150 W, respectively. Needless to say, the optimum development time and ultrasonic output vary depending on the conditions for forming the slurry film, the composition of the slurry, the exposure conditions, etc.

Although the above explanation has been made using a dot-type fluorescent surface as an example, the present invention is not limited to this, and can be similarly applied to the formation of a stripe-type fluorescent surface, which has become mainstream in recent years. By developing the slurry film after exposure using ultrasonic waves, it is possible to avoid peeling off of the phosphor pixels during the development process, which was conventionally done by hot water spray, and to produce high-quality color. It has the effect of forming a fluorescent surface of a picture tube, and is particularly useful for forming a fluorescent surface having fine picture elements.

[Brief explanation of the drawing]

Figures 1 and 2 are diagrams for explaining the slurry film coating process and exposure process, Figure 3 is a diagram showing an example of a dot type fluorescent surface, and Figure 4 is a diagram for explaining the conventional developing method. , FIG. 5 is a diagram showing an example of a dot type fluorescent surface formed by a conventional method, FIGS. 6 and 7 are diagrams for explaining the developing process in an embodiment of the present invention, and FIG.
The figure is a graph showing the dependence of the diameter of the phosphor dots formed on the ultrasonic development time. 1... Face panel, 2... Fluorescent slurry, 3... Shadow mask, 8... Ultrasonic transmitter, 9... Water tank. 4- 'w ＞1岨') -101-

Claims (1)

[Claims] The steps of applying a photosensitive phosphor slurry to the inner surface of the face panel to form a coating, exposing it to light through a shadow mask, and developing it are repeated for each color to create a phosphor layer made of phosphor pixels of each color. A method for forming a color picture tube fluorescent surface forming a light surface, wherein development is performed by immersing the exposed face panel in water and applying ultrasonic waves. .