JPH04259731A - Manufacture of color picture tube - Google Patents

Abstract

PURPOSE:To manufacture a color picture tube with less convergence error by doming phenomenon of a shadow mask without reducting the working efficiency. CONSTITUTION:On the metal back film 5 of a panel 1, a heat absorbing film 6 is formed by heating a material obtained by mining aluminium in a fixed weight ratio to manganese or a manganese compound and the metal manganese contained therein followed by pressurization and molding.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method of manufacturing a color picture tube, and more particularly to a color picture tube in which radiant heat from a shadow mask due to electron beam irradiation is absorbed into the opposing panel side, thereby reducing the doming phenomenon of the shadow mask. Relating to a manufacturing method.

0002

[Prior Art] Conventional methods for manufacturing color picture tubes, particularly in panel manufacturing, involve the use of green, blue, and red phosphors at predetermined positions on a black film made of graphite called a black matrix film on the inner surface of the panel. After forming the minute dots, a filming film made of an organic emulsion is formed to smooth the inner surface of the panel. Next 10-4~1
After performing vacuum evaporation of aluminum under a pressure of about 0-5 Torr to form a silver-white aluminum evaporated film, a so-called metal back film, further 10-1 to 10-1
A method has been proposed in which heat radiated from a shadow mask is absorbed by forming an oxidized black aluminum vapor deposition film by vapor depositing aluminum under a pressure of about 0-2 Torr (for example, Japanese Patent Publication No. 61-538
(See No. 16).

0003

[Problems to be Solved by the Invention] The above-mentioned conventional oxidized black aluminum film can be manufactured by a continuous process starting from the formation of a silvery white aluminum film as a metal back film, but it is difficult to manufacture at a low vacuum of 10-1 to 10-2 Torr. Since the aluminum is evaporated under the vacuum evaporation equipment, it is easy to contaminate the vacuum evaporation equipment, making it difficult to obtain a desired degree of vacuum. In other words, there is a problem in that the silver-white aluminum film which is the metal back film that is formed first is difficult to form, and the working efficiency of continuous vapor deposition is relatively lowered.

Another disadvantage is that the oxidized black aluminum film has large manufacturing variations, making it difficult to obtain the desired effect.

[0005]

[Means for Solving the Problems] The present invention includes a step of forming a black matrix film on the inner surface of a panel, a step of forming a phosphor layer on the black matrix film, and a metal back film on the phosphor layer. In the method of manufacturing a color picture tube, which includes the step of forming a metal back film, a mixture of manganese or a manganese compound and aluminum at a constant weight ratio to the metal manganese contained therein is pressure-molded. It is characterized by having a step of forming a heat absorbing film by heating and vapor depositing in a vacuum.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a sectional view of a panel portion of a color picture tube manufactured by a method according to a first embodiment of the present invention. FIG. 2 is a sectional view of a vacuum evaporation apparatus used in the present invention. The vacuum chamber 11 is connected to a rotary pump and a diffusion pump (not shown) and is evacuated. After putting the aluminum of the metal back film into the filament heater 13 and then putting the press-molded product made of manganese or a manganese compound and aluminum into the boat heater 12, the panel 14 on which the filming film has been formed is placed on the panel stand 16. I'll put it on. The filament heater 13 and the boat heater 12 are each connected to separate power sources at both ends, and can each be applied with an arbitrary voltage.

After mounting the panel 14, the inside of the vacuum chamber 11 is evacuated and the internal pressure of the vacuum chamber 11 is 10-4 to 10-5 Torr.
When the temperature reaches r, the filament heater 13 is energized to vapor-deposit aluminum which will become a metal back film. Thereafter, the boat heater 12 is energized, and vapor deposition is performed subsequent to the discharge of dissolved gas from the press-molded product consisting of manganese or a manganese compound and aluminum, which will become the heat-absorbing film.

To give an example of a 14" size panel, 15" per filament is used as aluminum for the metal back film in the filament heater 13.
Approximately 0 mg is supplied in the form of a cylinder. The pressure-molded product is made of manganese or manganese compound metal manganese (Mn).
) 1/3 of the equivalent weight of aluminum is mixed with powder and press-molded at 5t/cm2 or more, and the weight of the molded product is 50m per piece in terms of manganese (Mn) equivalent weight.
Make into pellets of about 1.5 oz. boat heater 12
One processed and molded pellet is supplied.

After the panel 14 is placed on the panel stand 16 and the inside of the vacuum chamber 11 is evacuated to 10 -4 to 10 -5 Torr, a current of about 100 A is applied to the filament heater 13 to deposit aluminum to form a metal back film. Subsequently, a current of about 60 A is applied to the boat heater 12 to degas and melt the pellets, which are press-molded manganese or manganese compound and aluminum, which will become the heat-absorbing film, and then increase the current to about 80 A to deposit the heat-absorbing film. I do. After the vapor deposition is completed, the pressure is returned to atmospheric pressure and the film is sent to the firing step and subsequent steps to decompose organic matter such as the filming film.

Next, a second embodiment will be described. After supplying the pressure-molded material (pellets) of manganese or manganese compound and aluminum to the boat heater 12, which will become a heat-absorbing film, evacuation of the vacuum chamber 11 is started, and the pressure inside the chamber is 10-1~10-1.
When the temperature reaches 10-2 Torr, a current of about 20 A is continued to flow to the boat heater 12 in advance to vent gas. After that, when the pressure inside the tank reaches 10-4 to 10-5 Torr, a metal back film of aluminum is vapor-deposited, and then a current of about 60 A is applied to the boat heater 12 to form a pressure-molded product of manganese or manganese compound and aluminum ( pellets) and then increase the current to about 80 A to deposit a heat absorbing film.

In this embodiment, since gas is continuously released, it is possible to obtain a similar heat-absorbing film even with manganese or a manganese compound having a low purity, such as manganese dioxide (about 85% purity), and it can be manufactured at low cost. It has the advantage of being possible.

[0013]

[Effects of the Invention] As explained above, in the present invention, a black-gray film is formed by vapor-depositing a pressure-molded product of manganese or a manganese compound and aluminum on a vapor-deposited aluminum film which is a metal back film of a panel. The doming phenomenon of the shadow mask can be suppressed by allowing the panel side to absorb the heat radiated from the shadow mask facing the panel.

[0014] Furthermore, there is extremely little contamination of the vacuum evaporation equipment.
Further, a mixture of manganese or a manganese compound and aluminum, which is a material for forming a black-gray film, is pressure-molded to form a lump (pellet), which makes it very easy to supply the material.

As a result, it is possible to manufacture a color picture tube with less color shift due to the doming phenomenon, without lowering the degree of vacuum or decreasing the production efficiency due to material supply.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a panel portion of a color picture tube manufactured according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a vacuum evaporation apparatus used in the present invention.

[Explanation of symbols]

1 Panel 2 Black matrix film 3 Phosphor layer 4 Filming film 5 Metal back film 6 Heat absorption film 11 Vacuum chamber 12 Boat heater 13 Filament heater 14 Panel 15 Shielding plate 16 Panel stand

Claims (1)

[Claims] 1. A color image receiving method comprising the steps of forming a black matrix film on the inner surface of a panel, forming a phosphor layer on the black matrix film, and forming a metal back film on the phosphor layer. In the tube manufacturing method, a mixture of manganese or a manganese compound and aluminum at a fixed weight ratio to the metal manganese contained therein is mixed and pressure-molded onto a metal back film, and then heated and vapor-deposited in a vacuum. A method for manufacturing a color picture tube, comprising the step of forming an absorption film.