JPH05314900A - Method for forming phosphor screen of color picture tube - Google Patents

Abstract

PURPOSE:To prevent uneven application of light-absorptive paint so as to provide a phosphor screen excellent in white uniformity by forming a light absorbing layer using specific light-absorptive paint in forming the phosphor screen of a color picture tube. CONSTITUTION:A resist coat 22 having a pattern corresponding to the electron beam through hole 21 of a shadow mask 3 is formed on the inner surface of a panel 1. Light-absorptive paint composed chiefly of carbon is applied to the inner surface of the panel 1 on which the resist film 22 is formed, and is dried to form a light-absorptive paint layer 24. The lightabsorptive paint layer 24 on the resist film 22 are removed along with the resist film 22 to form a light absorbing layer 25 having a gap for forming phsophor layers. Next, phosphor layers 11B, 11G, 11R are formed in the gap of the light-absorbing layer 25. In the above process, ligh-absorptive paint having a carbon concentration of 5 to 6wt.% and whose surface tension at 25 deg.C is adjusted to 35 to 45dyne/cm is used to form the light absorbing layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a phosphor screen of a color picture tube, and more particularly to a method for forming a phosphor screen of a color picture tube provided with a light absorbing layer having a matrix-like or stripe-like pattern.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a color picture tube has an envelope composed of a panel 1 and a funnel 2 integrally joined to the panel 1, and is mounted inside the panel 1. A phosphor screen 4 is formed on the inner surface of the panel 1 so as to face the shadow mask 3 having a large number of electron beam passage holes formed therein. On the other hand, 3 in the neck 5 of the funnel 2
An electron gun 7 that emits electron beams 6B, 6G, and 6R is arranged. Then, the three electron beams 6B, 6G, 6R emitted from the electron gun 7 are deflected by the magnetic field generated by the deflection yoke 8 mounted outside the funnel 2 to horizontally and vertically scan the phosphor screen 4. Thus, a structure for displaying a color image is formed.

As the phosphor screen 4, as shown in FIG.
A black matrix type phosphor screen in which dot-shaped three-color phosphor layers 11B, 11G, and 11R that emit blue, green, and red are formed in the gaps of the matrix-shaped light absorption layer 10, and as shown in FIG. In the gap of the stripe-shaped light absorption layer 10, blue,
Striped three-color phosphor layers 11B, 11 that emit green and red light
There is a black stripe type phosphor screen with G and 11R formed.

Conventionally, these phosphor screens first form a matrix-shaped or stripe-shaped light-absorbing layer 10, and then the three-color phosphor layers 11B and 11G are provided in the gaps of the light-absorbing layer 10.
, 11R are provided so as to be embedded.

The light absorbing layer 10 is formed by a photographic printing method by first applying a photosensitive solution to the inner surface of the panel 1 and drying it to form a photosensitive film, which is then formed in the electron beam passage hole of the shadow mask 3. After baking the corresponding pattern, it is developed and dried to form a dot-shaped or stripe-shaped resist film at the position where the three-color phosphor layer is formed. Then, a light-absorbing paint mainly composed of carbon is applied to the inner surface of the panel 1 and dried to form a light-absorbing paint layer, and then the light-absorbing paint layer on the resist film is formed together with the resist film. It is formed by peeling and removing.

By the way, when the phosphor screen 4 is formed by the above-mentioned method, if unevenness of the light-absorbing paint occurs in the light-absorbing paint layer formed by applying the light-absorbing paint, that part of the light-absorbing layer is formed. Of the three-color phosphor layers 11B, 11B so that the size of the matrix holes and stripes (gap portions) of the
There is a problem in that the emission areas of G and 11R change, leading to a decrease in white uniformity.

One of the causes of the uneven coating of the light absorbing paint is the drying of the dot-shaped or stripe-shaped resist film formed before the application of the light absorbing paint. That is, when the light-absorbing paint is applied on the resist film with uneven drying and partial unevenness of dryness, the flow of the light-absorbing paint changes between the dry part and the undried part, resulting in application and formation. This is because the thickness of the light-absorbing paint layer that changes is changed, and the light and shade can be changed.

Conventionally, the above-mentioned light absorbing layer is formed by applying a light absorbing paint after developing a photosensitive film having a pattern corresponding to the electron beam passage holes of the shadow mask 3 developed thereon. Until then, while the panel 1 is rotating, the heater and air are used to uniformly dry it in a short time.However, due to the index of the phosphor screen forming process, the temperature of the atmosphere, the humidity, and the changes over time in the material, etc. ,
In some cases, the resist film is not evenly dried, which causes uneven coating of the light absorbing paint.

[0009]

As described above, the dot-shaped or stripe-shaped 3 is conventionally provided in the gap portion of the light absorption layer.
The black matrix-type or black stripe-type phosphor surface on which the color phosphor layer is formed first forms a matrix-shaped or stripe-shaped light absorption layer, and the three-color phosphor layer is embedded in the gap between the light absorption layers. It is formed so as to be embedded. The light absorption layer is printed by a photo printing method on a photosensitive film formed on the inner surface of the panel with a pattern corresponding to the electron beam passage holes of the shadow mask, and then developed to form a dot shape at the position where the three-color phosphor layer is formed. Alternatively, after forming a stripe-shaped resist film and drying the resist film, a light-absorbing paint containing carbon as a main component is applied to form a light-absorbing paint layer. It is formed by peeling and removing the upper light absorbing paint layer.

Therefore, when unevenness in the dry state of the resist film causes uneven coating of the light-absorbing paint, the size of the matrix holes and stripes at that portion changes,
There is a problem in that the light emitting area of the three-color phosphor layer formed in the matrix holes and stripes changes, leading to a decrease in white uniformity.

The present invention has been made in order to solve the above-mentioned problems, and makes it possible to prevent uneven coating of the light-absorbing paint so as to obtain a fluorescent screen having excellent white uniformity. To aim.

[0012]

A resist film having a pattern corresponding to an electron beam passage hole of a shadow mask is formed on an inner surface of a panel, and a light containing carbon as a main component is formed on the inner surface of the panel on which the resist film is formed. After applying absorptive paint and drying to form a light-absorbing paint layer, remove the light-absorbing paint layer on the resist film together with the resist film to form a phosphor layer and form a light-absorbing material. Forming layers,
In the method for forming a fluorescent screen of a color picture tube in which a phosphor layer is formed in the gap of the light absorbing layer, the carbon concentration in the light absorbing paint is 5 to 6% by weight, and the light absorbing paint has a temperature of 25 ° C.
With the surface tension at 35 to 45 dyne / cm 2, a light absorbing layer was formed from this light absorbing paint.

[0013]

As described above, the carbon concentration is 5 to 6% by weight,
Moreover, if the light absorbing layer is formed by using a light absorbing paint having a surface tension at 25 ° C. of 35 to 45 dyne / cm, the familiarity with the resist film becomes good, and the dry state of the resist film is uneven and partially un-coated. Even if a dry portion is formed, the light absorbing paint can be applied uniformly, and uneven coating of the light absorbing paint layer can be eliminated.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

As shown in FIG. 1A, while the panel 1 is being rotated, polyvinyl alcohol (PVA) is applied to the inner surface of the panel 1.
Then, a photosensitive solution containing ammonium dichromate (ADC) as a main component is applied, excess photosensitive solution is removed, and then dried to form a photosensitive film 20. Next, as shown in (b), a shadow mask 3 is attached to the inside of the panel 1 on which the photosensitive film 20 is formed, and the photosensitive film 20 is radiated from a mercury lamp or the like through the shadow mask 3. Exposure is performed by irradiating ultraviolet rays, and a pattern corresponding to the electron beam passage hole 21 of the shadow mask 3 is printed. Shadow mask 3
Then, while rotating the panel 1, the photosensitive film 20 having the pattern corresponding to the electron beam passage hole 21 of the shadow mask 3 is developed to remove the unexposed portion, dried, and the same (c). As shown in, a resist film 22 having a dot-shaped or stripe-shaped pattern is formed at the position where the three-color phosphor layer is formed.

Next, while rotating the panel 1, the following light-absorbing coating material containing carbon as a main component was applied to the inner surface of the panel 1 having the resist film 22 formed thereon, and the excess light-absorbing coating material was removed. After that, it is dried to form a light absorbing paint layer 24 on the inner surface of the panel 1 on which the resist film 22 is formed, as shown in FIG.

As the above-mentioned light-absorbing coating material, in this phosphor screen forming method, one having a carbon concentration of 5 to 6% by weight and a surface tension at 25 ° C. of 35 to 45 dyne / cm is used. The surface tension can be adjusted by, for example, the surfactant Pl.
It is obtained by adding uronic L-92 (manufactured by Wyandotte Chemical Co., Ltd.).

Next, a decomposing agent for the resist film 22 containing hydrogen peroxide as a main component is injected into the panel 1 having the light absorbing coating layer 24 formed thereon, and the resist film 22 is peeled off,
Along with the resist film 22, the light absorbing paint layer 24 on the resist film 22 is removed, washed with water, and dried to form a black matrix having a three-color phosphor layer forming position as a gap as shown in (e). Alternatively, the light absorption layer 25 having a black stripe pattern is formed.

Thereafter, as shown in (f), while rotating the panel 1 on which the light absorption layer 24 is formed, an arbitrary phosphor such as a blue phosphor, PVA and AD is formed on the inner surface of the panel 1.
A phosphor slurry containing C as a main component is applied, excess phosphor slurry is removed and dried to form a phosphor slurry layer 26. Next, as shown in (g), the phosphor slurry layer
A shadow mask 3 is attached to the inside of the panel 1 on which the 26 is formed, and the phosphor slurry layer 26 is exposed through the shadow mask 3 with ultraviolet rays emitted from a mercury lamp or the like to form a blue phosphor. A pattern corresponding to the electron beam passage hole 21 of the shadow mask 3 is printed on the position. Then, the shadow mask 3 is removed, and while rotating the panel 1, the phosphor slurry layer 26 having the pattern corresponding to the electron beam passage hole 21 of the shadow mask 3 is developed to remove the unexposed portion and dried. Then, as shown in (h),
A dot-shaped or stripe-shaped blue phosphor layer 11B is formed at the blue phosphor layer formation position.

Next, with respect to the green phosphor and the red phosphor, the formation method of the blue phosphor layer 11B is repeated, and as shown in (i), the green and red phosphor layers 11g are formed at the respective phosphor layer forming positions. , 11R is formed.

By the way, when the light absorbing paint layer 24 is formed on the inner surface of the panel 1 on which the resist film 22 is formed as described above, the carbon concentration of the light absorbing paint is set to 5 to 6% by weight,
When a light-absorbent coating material having a surface tension changed by adding a surfactant to this is applied, a relationship shown by a curve 28 in FIG. 2 is obtained between the light-absorbent coating material layer to be formed.

That is, even if a surfactant is added,
If the surface tension at 35 ° C. is less than 35 dyne / cm, spot-like unevenness is likely to occur partially depending on the dry state of the resist film. Further, when the surface tension exceeds 45 dyne / cm, uneven coating of the light absorbing coating occurs on the uneven dry portion of the resist film. However, in this case, if there is no unevenness in drying of the resist film, unevenness in coating does not occur even if the surface tension is about 50 dyne / cm. That is, regardless of the dry state of the resist film, in order to form a uniform light-absorbing paint layer, the surface tension of the light-absorbing paint should be 35 to 45 dyne / cm (25 ° C). When the light absorbing layer is formed by using the light absorbing paint adjusted to the range, it is possible to eliminate uneven coating of the light absorbing paint and form a fluorescent screen having excellent white uniformity.

[0023]

EFFECTS OF THE INVENTION A resist film having a pattern corresponding to the electron beam passage holes of a shadow mask is formed on the inner surface of the panel, and a light-absorbing coating material containing carbon as a main component is formed on the inner surface of the panel on which the resist film is formed. After coating and drying to form a light-absorbing paint layer, the light-absorbing paint layer on the resist film is removed together with the resist film to form a light-absorbing layer having a gap for forming a phosphor layer. In the method for forming a phosphor screen in a color picture tube, wherein a phosphor layer is formed in a gap portion of the light absorbing layer, the carbon concentration in the light absorbing paint is 5 to 6% by weight, and the light absorbing paint has a temperature of 25 ° C. If the surface tension at 35 is 45 to 45 dyne / cm, the compatibility with the resist film will be improved, and even if the dry state of the resist film changes, the light absorbing paint can be applied uniformly, Remove uneven paint , It is possible to form an excellent fluorescent screen of a white Yuniho proximity.

[Brief description of drawings]

1A to 1I are views for explaining a method for forming a fluorescent screen of a color picture tube according to an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the surface tension and film formability of a light-absorbing coating material applied to the inner surface of a panel on which a resist film is formed to form the light-absorbing layer.

FIG. 3 is a diagram showing a configuration of a color picture tube.

FIG. 4 (a) is a plan view showing the structure of the black matrix type phosphor screen, and FIG. 4 (b) is a sectional view thereof.

5 (a) is a plan view showing the structure of the black stripe type phosphor screen, and FIG. 5 (b) is a sectional view thereof.

[Explanation of symbols]

 1 ... Panel 3 ... Shadow mask 11B, 11G, 11R ... Three-color phosphor layer 20 ... Photosensitive film 21 ... Electron beam passage hole 22 ... Resist film 24 ... Light absorbing paint layer 25 ... Light absorbing layer 26 ... Phosphor slurry layer

Claims (1)

[Claims] 1. A resist film having a pattern corresponding to an electron beam passage hole of a shadow mask is formed on the inner surface of the panel, and a light-absorbing coating material containing carbon as a main component is formed on the inner surface of the panel on which the resist film is formed. After coating and drying to form a light-absorbing paint layer, the light-absorbing paint layer on the resist film is removed together with the resist film to form a light-absorbing layer having a gap for forming a phosphor layer. In the method for forming a phosphor screen of a color picture tube, in which a phosphor layer is formed in the gap portion of the light absorbing layer, the carbon concentration in the light absorbing coating is set to 5 to 6% by weight, and The surface tension at 25 ° C is 35-35.
A method for forming a fluorescent screen of a color picture tube, characterized in that the light absorbing layer is formed with this light absorbing paint at 45 dyne / cm 2.