JPH0461732A - Color cathode-ray tube - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a color cathode ray tube, and more particularly to a color cathode ray tube in which a shadow mask is supported inside the panel in a removable manner and with good reproducibility. .

(Prior art) In general, a color cathode ray tube has a phosphor screen formed on the inner surface of the panel of the envelope, which is composed of three-color phosphor layers that emit blue, green, and red light, and a large number of electron beams pass through the inside of the phosphor screen. A shadow mask with holes is arranged, and the three electron beams emitted from the electron gun are deflected by the magnetic field generated by the deflection yoke, and then the phosphor screen is horizontally and vertically scanned through the shadow mask. It is formed in a structure that displays a color image on a phosphor screen.

Originally, the above-mentioned shadow mask was used to select the three electron beams emitted from the electron gun so that they would land correctly on the three-color phosphor layer, and for this purpose, the three-color phosphor layer and the shadow mask had to be in a matching relationship. must be placed.

Incidentally, the phosphor screen of the color cathode ray tube is formed by assembling a panel-mask assembly by combining a panel and a shadow mask in a predetermined relationship, and then forming the panel-mask assembly by a photoprinting method.

That is, as shown in FIG. 4(a), the shadow mask is removed from the panel/mask assembly and the panel (1
) After coating the inner surface with a phosphor slurry layer (2) containing phosphor and photosensitizer as main components, the removed shadow mask was attached to the panel (1) and exposed as shown in (b). irradiating the phosphor slurry layer (2) with light from a light source (not shown) through the shadow mask (3);
A pattern corresponding to the electron beam passing hole (4) of the shadow mask (3) is printed. Thereafter, the shadow mask (3) is removed from the panel (1), and the phosphor slurry layer (
2) is developed to remove the unexposed area, and as shown in (c), a phosphor layer (5) is formed. By repeating this phosphor layer forming method for three-color phosphors, three-color phosphor layers (5B) and (5G) are formed as shown in (d).

(5R) is formed. The fluorescent screen formed in this way is
Thereafter, as shown in (e), an aluminum film (6) is formed by vacuum deposition on the three-color phosphor layers (5B), (5G), and (5R).

The panel on which the phosphor screen is formed is then attached with the shadow mask, and then integrally joined with the funnel, and the electron gun is further sealed and evacuated to form a color cathode ray tube.

Therefore, the shadow mask (3) is attached and detached multiple times after the panel-mask assembly is assembled and before it is installed inside the tube. Therefore, as shown in Figure 5, multiple shadow masks (3) have been conventionally installed on the panel (1) to make it easy to attach and detach from the panel (1) and to ensure that the shadow mask (3) is always correctly attached even after repeated attachment and detachment. stud pin (7)
On the other hand, a plurality of elastic supports (8) are attached to the underarm mask (3) corresponding to the plurality of stud pins (7).
), and the fitting hole formed at the free end of each elastic support (8) is fitted and locked to each stud pin (7), so that it is removably attached to the inside of the ribanell (1). It is organized into a structure.

Such a stud pin (7) and an elastic support (8)
In particular, the stud pins (7) attached to the panel (1) are made of a stainless steel material whose coefficient of thermal expansion is similar to that of the glass constituting the panel (1), as shown in FIG. , about 1Oμ thick on the surface
It is formed by an oxidized film (IO) in the intestine. This oxide film (10) improves compatibility with the glass, increases the strength of its attachment, and also serves as rust prevention for the stud pin (7).

Therefore, this oxide film (lO) is an important component that the stud pin should have as a mask support means.
As can be seen from the curve (12) in the figure, the oxide film has a large surface roughness and irregularities of 3 to 6 μm.

Therefore, as shown in Figure 8, this stud pin (7
) When attempting to fit and lock the elastic support (8) attached to the shadow mask, due to the frictional resistance based on the surface roughness, the correct fit and lock shown by the solid line will occur as shown by the broken line. It may shift and not fit and lock in the same position. If the position of the shadow mask when forming the three-color phosphor layer differs from the position of the shadow mask after it is attached to the tube due to the misalignment of the elastic support (8) with respect to the stud pin (7), the three-color The landing of the electron beam on the phosphor layer is deviated, making it difficult to adjust the color purity, and when the deviance exceeds the landing margin of the three-color phosphor layer, color deviation occurs and image quality is degraded.

(Problem to be solved by the invention) As mentioned above, the shadow mask of a color cathode ray tube is
This is to select the three electron beams emitted from the electron gun so that they land correctly on the three-color phosphor layer, and for this purpose, the three-color phosphor layer and each electron beam passage hole of the shadow mask have a matching relationship. must be placed in On the other hand, the shadow mask is attached and detached multiple times during the manufacturing process of color cathode ray tubes, from when the panel/mask assembly is assembled until it is installed inside the tube. Therefore, the shadow mask has a plurality of stud pins attached to the panel so as to always satisfy the alignment relationship even when the shadow mask is attached and detached multiple times, and a plurality of elastic supports are attached to the shadow mask corresponding to the stud pins. The structure is such that it can be removably attached to the inside of the panel by fitting and locking the fitting hole formed at the free end of each elastic support to each stud pin.

However, conventional stud pins are made of stainless steel material whose coefficient of thermal expansion is similar to that of the glass that makes up the panel, so that they fit well with the glass that makes up the panel, increase the strength of the installation, and protect the stud pin. An oxide film with a thickness of about 10 μl is formed on the surface, which also serves as rust. This oxide film (10) is an important component that the stud pin should have as a mask support means, but since this oxide film has a large surface roughness, the elasticity of the stud pin attached to the shadow mask When you try to fit and lock the support, it may not fit and lock in the same position due to frictional resistance based on its surface roughness, so 3
If the position of the shadow mask when forming the color phosphor layer is different from the position of the shadow mask after being attached to the tube,
The landing of the electron beam on the three-color phosphor layer is shifted, which not only makes it difficult to adjust the color purity, but also makes it difficult to adjust the color purity.
If the landing margin of the color phosphor layer is exceeded, there is a problem that color shift occurs and image quality deteriorates.

This invention was made to solve the above problem, and even if the shadow mask is repeatedly attached and detached from the panel, the elastic support body attached to the shadow mask is always fitted in the same position with respect to the stud pin. The purpose of this invention is to provide a structure that allows highly precise reproducibility to be obtained by locking and mating.

[Structure of the Invention] (Means for Solving the Problems) A shadow mask having a large number of electron beam passage holes formed inside the panel is fixed to the shadow mask with a plurality of stud pins fixed to the inner surface of the skirt portion of the panel. An oxide film is formed on the entire surface of the stud pin in a color cathode ray tube which is removably supported by a mask support means comprising an elastic support member formed with a fitting hole that fits and locks the stud pin. Then, a carbon film was formed on the oxide film of the engaging portion of the stud pin into which the fitting hole of the elastic support was fitted and locked.

(Function) As described above, when a carbon film is deposited on the oxide film of the engaging part where the fitting hole of the elastic support of the stud pin fits and locks, the carbon film is oxidized on the surface of the engaging part. It fills in the unevenness of the film and flattens its surface, and the excellent lubricity of the carbon film reduces the frictional resistance when fitting and locking the elastic support to the stud pin, making it elastic against the stud pin. Since the support can always be fitted and locked in the same position, highly accurate reproducibility can be achieved.

(Example) Hereinafter, the present invention will be described based on an example with reference to the drawings.

FIG. 1 shows a color cathode ray tube, which is one embodiment of the present invention.

This color cathode ray tube has a skirt section (20) on the periphery.
A glass panel (21) formed with a glass panel (21) and a funnel-shaped funnel (22) integrally joined to this panel (21).
), and on the inner surface of the panel (21),
A phosphor screen (2
3) is formed, and facing this phosphor screen (23), there is a mask body (24) with a large number of electron beam passing holes formed inside the panel (21), and a mask body (24) with a cross-section shaped like an angular shape attached to its periphery. A shadow mask (26) consisting of a mask frame (25) is mounted by the following mask support means.

There are also 3 electron beams (28B) and (28G) in the neck (27) of the funnel (22).

An electron gun (29) that emits (281?) is provided.

The three electron beams (28B), (28G), and (28R) emitted from the electron gun (29) are then directed to a deflection yoke (30) attached to the outside of the funnel (22).
The phosphor screen (23) is deflected by a magnetic field generated by the phosphor screen (23) to horizontally and vertically scan the phosphor screen (23), thereby displaying a color image on the phosphor screen (23).

The mask supporting means includes a plurality of stud pins (3) fixed to the inner surface of the skirt portion (20) of the panel (21).
2), and an elastic support (33) fixed to the outer surface of the mask frame (25) in correspondence with each stud pin (32), and a free end portion of the elastic support (33). The shadow mask (26) is removably supported inside the panel 21 by fitting and locking the formed fitting holes into the corresponding stud pins (32).

The stud pin (32) is made of stainless steel with a coefficient of thermal expansion close to that of the glass constituting the panel.
35) and a tapered locking part (36) into which the elastic support (33) fits and locks. When mounting to a panel, an oxide film (37) with a thickness of about 10 μm is formed to increase the strength, and a locking part (3B) is formed.
) A conductive carbon film (38) with a thickness of about 15 μm is formed on the oxide film (37) on the outer surface.

This stud pin (32) is formed into a predetermined shape by press molding, and then heat-treated in an oxidizing gas atmosphere to form an oxide film (37) on the surface. The carbon film (38) is manufactured by applying the carbon dispersion by soaking it into a sponge, for example, and then air-drying the applied carbon dispersion or baking it at a temperature of 450° C. or lower to form a carbon film (38).

In addition to the method described above, the carbon film (38) can be formed by holding the stud pin (32) so that the locking part (36) is exposed on the plate surface, as shown in FIG. A stud pin (32) is attached to a retaining plate (41) in which a plurality of retaining holes (40) are formed, and the carbon dispersion liquid is spray applied to the locking part (36) exposed on the plate surface, and dried. Afterwards, the coated film can be polished with a sponge or the like.

By the way, when the carbon film (38) with a film thickness of about 15 μm is formed on the locking part (3B) of the stud pin (32) as described above, the unevenness of about 3 to 6 μm in the oxide film (37) underneath is formed. The four parts are embedded and flattened by the carbon film (38), and since the carbon film (38) has extremely good lubricity, the frictional resistance that conventionally occurs due to the surface roughness of the stud pin is eliminated. Preventing the fitting and locking position of the elastic support body from changing with respect to the stud pin,
Shadow mask (
Even when the shadow mask (26) is attached and detached a plurality of times, the shadow mask (26) can be always attached at the same position by preventing its positional shift.

Therefore, it is possible to configure a color cathode ray tube with easy and good color purity adjustment.

[Effects of the Invention] A mask support means comprising a stud pin fixed to the inner surface of the skirt portion of the panel and an elastic support fixed to the shadow mask and having a fitting hole that fits and locks with the stud pin. Then, when a carbon film is formed on the oxide film of the engaging part where the elastic support of the stud pin fits and locks, the carbon film flattens the unevenness of the oxide film on the surface of the engaging part, and The excellent lubricity of the carbon coating reduces the frictional resistance when fitting and locking the elastic support to the stud pin, making it possible to always fit and lock the elastic support in the same position. It is possible to prevent the shadow mask from shifting even when the shadow mask is attached to and detached from the panel multiple times in the manufacturing process, and to construct a color cathode ray tube with easy and good color purity adjustment.

[Brief explanation of the drawing]

1 to 3 are detailed explanatory diagrams of the present invention, in which FIG. 1 shows the structure of a color cathode ray tube that is an embodiment of the invention, FIG. 2 shows the structure of its stud pin, and FIG. The figure is a diagram for explaining the manufacturing method of the stud pin.
Figures (a) to (e) are diagrams for explaining the method of forming a phosphor screen of a color cathode ray tube, respectively, and Figures 5 (a) and (
b) Each end is a plan view and a sectional view showing the support means for the shadow mask to the panel, FIG. 6 is a diagram showing the configuration of a conventional stud pin, and FIG. 7 is a diagram showing the surface roughness of a conventional stud pin. , FIG. 8 is a diagram for explaining the state in which the elastic support body is fitted and locked to the stud pin. 20...Skirt part, 21...Panel, 23...
Fluorescent screen, 24... Mask body, 25... Mask frame, 32... Stud pin, 35... Fixing part, 37... Oxide film, 26... Shadow mask, 33... Elasticity Support body, 36...Locking part, 38... Carbon coating.

Claims (1)

[Claims] A shadow mask having a large number of electron beam passing holes is disposed inside a panel having a skirt portion on the periphery, and this shadow mask has a plurality of shadow masks fixed to the inner surface of the skirt portion of the panel. In the color cathode ray tube detachably supported by a mask support means consisting of stud pins and an elastic support fixed to the shadow mask and having a fitting hole that fits and locks with the stud pin, An oxide film is formed on the entire surface of the stud pin, and a carbon film is formed on the oxide film at the engaging portion of the stud pin where the fitting hole of the elastic support body is fitted and locked. Features a color cathode ray tube.