JPH10340692A - Fluorescent character display tube and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent character display tube and its manufacture wherein (Zn, Cd) S:Ag, Cl phosphor that is difficult to be patterned due to its body color which absorbs ultraviolet light easily can be patterned surely without making a missing portion in a pattern. SOLUTION: A precoat liquid 10 which is made by dissolving PVA-sbq (styryl pyridinium group pendant-polyvinyl alcohol) in pure water is applied along insulating layers 3 on a positive electrode substrate 1 using a doctor blade coat method and dried, so that a precoat layer is obtained. A phosphor slurry liquid 12 which contains PVA-sbq, (Zn, Cd) S:Ag, Cl phosphor, a conductive material of In2 O3 , pure water, and a surface active agent is applied on the precoat layer and dried, so that a phosphor layer is formed. This phosphor layer is exposed to ultraviolet light through a photomask and spray developed with warm water. Since only light-exposed areas in the phosphor layer are insolbulized due to a photocrosslinking reaction the phosphor layer of a desired pattern is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a technique for forming a phosphor layer having a desired pattern by irradiating a phosphor slurry liquid layer containing a photosensitive agent with ultraviolet rays through a photomask. In particular, the present invention relates to a fluorescent display tube in which a phosphor of a body color that easily absorbs ultraviolet light is patterned with a certain adhesion strength, and a method of manufacturing the same.

[0002] Phosphors having a body color that easily absorbs ultraviolet rays include, for example, sulfide-based red light-emitting phosphors. These phosphors are used in fluorescent printer heads and the like that record images by exposing to silver halide paper. Therefore, the fluorescent display tube of the present invention is useful as a light source for a printer used for recording means such as a silver halide printer.

The fluorescent display tube of the present invention further includes a video printer, an electrophotographic printer, a label printer, and the like.
It can also be used for general fluorescent display tubes and fluorescent light emitting tubes as light sources.

[0004]

2. Description of the Related Art A fluorescent printer head used in a fluorescent printer proposed by the present applicant will be described as an example of a fluorescent display tube. The fluorescent printer head has an envelope formed by assembling a glass plate into a box shape with sealing glass. The inside of the envelope is in a high vacuum state. A large number of light emitting dots are arranged along the main scanning direction at a predetermined interval and arrangement on the inner surface of the anode substrate which forms a part of the envelope. The light emitting dots are formed by providing a phosphor layer on an anode conductor having a transparent hole, and light from the light emitting dots is applied to the outside of the envelope through the transparent hole and the anode substrate.

A drive signal based on the image signal is applied to the printer head to turn on each light-emitting dot, and in synchronization with this, the silver halide paper as the object of image formation and the fluorescent printer head relatively move in the sub-scanning direction. . Dot light emitted from the fluorescent printer head reaches the silver halide paper,
An image (or a latent image corresponding to the image) is formed on the silver halide paper.

A description will be given of the pattern formation of the phosphor in the light emitting dots of the above-described fluorescent printer head. FIG.
As shown in (a), an aluminum electrode 2 serving as an anode conductor is formed on an anode substrate 1 by a chemical etching method, and an insulating layer 3 is formed on the anode substrate 1 on both sides thereof.
On the aluminum electrode 2, a precoating solution, which is an aqueous solution having a concentration of 0.05 to 0.20 wt% of polyvinyl alcohol (PVA), is applied over the entire surface by a doctor blade coating method and dried to form a precoating layer 4. A photosensitive slurry liquid 5 containing a phosphor is applied thereon. The photosensitive slurry liquid 5 has a styrylpyridinium group pendant polyvinyl alcohol (P) having a structure shown in FIG.
VA-sbq), (Zn, Cd) S: Ag, Cl which is a yellow-red light-emitting phosphor of a body color, and a pluronic surfactant in a desired ratio. This photosensitive slurry liquid is applied onto the precoat layer 4 by a doctor blade coating method, and dried. After that, the photosensitive slurry liquid 5 is exposed by an ultra-high pressure mercury lamp through a photomask 6 on which a predetermined pattern is formed. The exposed portions are cured by a crosslinking reaction and are insoluble in water. 40 ℃
Spray development is performed with about warm pure water, and Fig. 2 (b)
A desired pattern is formed as shown in FIG. Thereafter, this is fired to obtain the phosphor layer 7.

[0007]

The body color is yellow (Zn,
Cd) S: Ag, Cl phosphor is an indispensable phosphor for exposing silver halide paper having a cyan coloring layer with a fluorescent printer head, but has the following problems. (Zn, Cd) S: Ag, Cl, which is a red light-emitting phosphor, has a yellow body color and therefore easily absorbs ultraviolet light during the above-described exposure. For this reason, in the deep part of the film of the photosensitive slurry liquid applied on the anode substrate, the amount of transmitted ultraviolet light is drastically reduced, and a sufficient photocrosslinking reaction cannot be obtained. As a result, the exposed portion of the applied photosensitive slurry liquid film, which should be cured, is in an uncured state. Therefore, this portion is removed at the time of development, and the pattern is lost. There was a problem that it would. 1

Although the precoat liquid is used to obtain the adhesion strength between the phosphor layer and the anode substrate, in practice, a sufficient effect cannot be obtained, and (Zn, Cd)
The phosphor layer of S: Ag, Cl was insufficient in adhesion strength to the anode substrate side, and was almost missing during development and could not be used as a product.

SUMMARY OF THE INVENTION It is an object of the present invention to surely form a pattern of a phosphor having a body color which easily absorbs ultraviolet rays without a missing portion by a photocrosslinking reaction using ultraviolet rays.

[0010]

According to a first aspect of the present invention, there is provided a fluorescent display tube including a pre-coat layer on an envelope whose inside is in a high vacuum state and an anode conductor provided on an inner surface of the envelope. In a fluorescent display tube having an anode on which a phosphor is adhered through an electron source and an electron source provided inside the envelope, the precoat layer is formed of a styrylpyridinium-based pendant polyvinyl alcohol (PVA-sbq). Is formed by a pre-coating solution containing a styrene-pyridinium-based pendant polyvinyl alcohol (P
VA-sbq) and a phosphor slurry liquid containing a phosphor whose body color is ultraviolet absorbing.

According to a second aspect of the present invention, there is provided the fluorescent display tube according to the first aspect, wherein the fluorescent substance is (Z
(n, Cd) S-based phosphor.

According to a third aspect of the present invention, there is provided the fluorescent display tube according to the second aspect, wherein the (Zn, Cd) S
The system is characterized in that the phosphor is (Zn, Cd) S: Ag, Cl.

According to a fourth aspect of the present invention, there is provided the fluorescent display tube according to the second aspect, wherein the (Zn, Cd) S
The system is characterized in that the phosphor is (Zn, Cd) S: Ag, Al.

According to a fifth aspect of the present invention, there is provided a method for manufacturing a fluorescent display tube, comprising: a pre-coating layer provided between an envelope in which a high vacuum state is provided and an anode conductor provided on an inner surface of the envelope; In a method of manufacturing a fluorescent display tube having an anode having a body attached thereto and an electron source provided inside the envelope,
A precoat solution containing styrylpyridinium-based pendant polyvinyl alcohol (PVA-sbq) is applied on the anode conductor to form the precoat layer, and a styrylpyridinium-based pendant polyvinyl alcohol (PVA) is formed on the precoat layer. -Sbq) and a phosphor slurry containing a phosphor whose body color is UV-absorbing to form a phosphor layer, and irradiating ultraviolet rays through a photomask to perform wet development, It is characterized in that the phosphor layer is formed in a desired pattern.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have found that, in the above-mentioned conventional phosphor layer manufacturing process, the body color is yellow and UV (Zn, Cd) S: Ag,
The reason why the Cl phosphor was lost during development was considered. As a result, the above-mentioned conventional precoat liquid is PVA
Since it is an aqueous solution and does not have a photosensitive group, and there is an indirect photoreaction by ultraviolet irradiation, there is no direct reaction with the phosphor slurry solution, so the phosphor layer should be attached to the anode substrate side. I came to think that I could not do it.

Therefore, the present inventors have made the precoat solution contain the same photosensitive agent as the photosensitive agent in the phosphor slurry solution, and promoted a cross-linking reaction at the interface between the anode substrate and the phosphor layer to form a phosphor layer. A new idea of improving the bonding strength has been obtained.

A fluorescent printer head of a fluorescent printer proposed by the present applicant will be described as an example of a fluorescent display tube to which the present invention is applied. First, the fluorescent printer is provided with three fluorescent printer heads having the same basic structure as a general fluorescent display tube. Each fluorescent printer head emits red, green, and blue light, respectively. Each fluorescent printer head has an envelope in which a glass plate is assembled in a box shape by sealing glass. The inside of the envelope is in a high vacuum state. A large number of light emitting dots are arranged along the main scanning direction at a predetermined interval and arrangement on the inner surface of the anode substrate which forms a part of the envelope. The light emitting dots are formed by providing a phosphor layer on an anode conductor having a transparent hole, and light from the light emitting dots is applied to the outside of the envelope through the transparent hole and the anode substrate.

The fluorescent printer head for blue uses a ZnO: Zn phosphor emitting green light for the light emitting dots, and a blue filter is provided outside the anode substrate. The green fluorescent printer head uses green light-emitting Zn
An O: Zn phosphor is used, and a green filter is provided outside the anode substrate. The fluorescent printer head for red has the above-mentioned red light emitting (Zn, Cd) in the light emitting dots.
S: Ag, Cl phosphor is used, and a red filter is provided outside the anode substrate.

The three fluorescent printer heads R, G and B are arranged along the sub-scanning direction orthogonal to the main scanning direction so that the light emitting dot rows parallel to the main scanning direction are parallel to each other. A drive signal based on the color-separated image signal is applied to each printer head to illuminate each light-emitting dot, and in synchronization with this, the silver halide paper to be image-formed and each fluorescent printer head are relatively moved in the sub scanning direction. Go to The dot light of each color emitted from each fluorescent printer head reaches the silver halide paper, and an image (or a latent image corresponding to the image) is formed on the silver halide paper.

In the structure of the fluorescent printer head according to the present embodiment, the parts not particularly described are the same as those in the related art.
The fluorescent printer head of this embodiment is characterized by a precoat layer and a phosphor layer and their manufacturing steps. These will be described below.

The precoat liquid 10 of the present embodiment is the same as the above-described PV.
A-sbq is dissolved in pure water so as to have a concentration of 40 wt%, and is applied along the insulating layer on the anode substrate by a doctor blade coating method using a blade 11 as shown in FIG. Dry at 100 ° C. for 5 minutes to form a precoat layer. Next, the above-mentioned PVA-sbq was
0 wt%, phosphor (Zn, Cd) S: Ag, Cl 50
wt%, 5 wt% of In ₂ O ₃ as a conductive material, pure water 1
The phosphor slurry liquid 12 is mixed at 4.9 wt% and a surfactant at 0.1 wt%. This phosphor slurry liquid 12 is
It is applied on the precoat layer by the doctor blade coating method in the same manner as the precoat liquid 10. The phosphor layer is formed by drying at 90 ° C. for 5 minutes.

Next, an ultra-high pressure mercury lamp is used for 900 900 through a photomask on which a pattern of light emitting dots is formed.
The phosphor layer is exposed at an exposure amount of mJ / cm ² . Next, spray development is performed with warm water at 30 to 40 ° C. In the phosphor layer containing the negative-type PVA-sbq photosensitizer, only a portion irradiated with light is insoluble in water by a photocrosslinking reaction, and a portion not irradiated with light is dissolved in water. A corresponding desired pattern of the phosphor layer is formed.

In silver halide paper having cyan, yellow and magenta color layers, the sensitivity of the cyan layer is generally lower than that of the yellow and magenta layers. Therefore, for practical use of a fluorescent printer head, red light emission with sufficient luminance can be obtained (Zn, Cd) S: Ag,
It has been desired to use a Cl phosphor, but conventionally it could not be used due to the problems described above. However, according to the present example, (Zn, Cd) S: Ag,
Since a pattern of the Cl phosphor can be formed, a fluorescent printer capable of exposing to silver halide paper can be realized.

In the example described above, (Zn, Cd) S: Ag, C
Although l is mentioned, the present invention can be applied to other (Zn, Cd) S-based sulfide phosphors, for example, (Zn, Cd) S: Ag, Al and the like.

[0025]

According to the fluorescent display tube and the method of manufacturing the same of the present invention, in order to pattern a phosphor which easily absorbs ultraviolet light with a reliable adhesive force, both the precoat liquid and the phosphor slurry liquid are provided with styrylpyridinium. A base pendant polyvinyl alcohol (PVA-sbq) was included.
For this reason, the cross-linking reaction at the interface between the anode substrate and the phosphor layer is promoted, the adhesion strength of the phosphor layer is improved, and the ultraviolet ray transmittance in the depth direction of the film is reduced in the phosphor that easily absorbs ultraviolet rays. An enormous effect can be obtained in preventing the separation at the interface with the anode substrate.

Specifically, the body color is yellow (Zn, Cd)
Even with the S: Ag, Cl phosphor, a good phosphor layer pattern with no loss can be obtained, and the red light-emitting phosphor (Z
Since a phosphor pattern containing (n, Cd) S: Ag, Cl can be formed, a fluorescent printer head capable of exposing silver halide paper can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a step of applying a precoat liquid or a phosphor slurry liquid on an anode substrate side by a doctor blade coating method in this example.

FIG. 2 is a diagram showing a manufacturing process of a phosphor layer in a fluorescent printer proposed by the present inventors.

FIG. 3 is a structural diagram of a styrylpyridinium group pendant polyvinyl alcohol (PVA-sbq).

[Explanation of symbols]

 10 Precoat liquid 12 Phosphor slurry liquid

Claims (5)

[Claims] 1. An envelope whose inside is in a high vacuum state, an anode in which a phosphor is applied to an anode conductor provided on an inner surface of the envelope via a precoat layer, and A fluorescent display tube having an electron source provided inside a vessel, wherein the precoat layer is formed of a precoat liquid containing a styrylpyridinium-based pendant polyvinyl alcohol (PVA-sbq), and the phosphor is styrylpyridinium. A fluorescent display tube formed of a phosphor slurry liquid containing a base pendant polyvinyl alcohol (PVA-sbq) and a phosphor having a body color absorbing ultraviolet rays. 2. The fluorescent display tube according to claim 1, wherein the phosphor is a (Zn, Cd) S-based phosphor. 3. The (Zn, Cd) S-based phosphor comprises:
3. The fluorescent display tube according to claim 2, wherein (Zn, Cd) S: Ag, Cl. 4. The (Zn, Cd) S-based phosphor comprises:
The fluorescent display tube according to claim 2, wherein (Zn, Cd) S: Ag, Al. 5. An envelope whose inside is in a high vacuum state, an anode in which a phosphor is applied to an anode conductor provided on the inner surface of the envelope via a precoat layer, and A method for manufacturing a fluorescent display tube having an electron source provided inside a vessel, wherein a precoat liquid containing a styrylpyridinium-based pendant polyvinyl alcohol (PVA-sbq) is applied on the anode conductor, Is formed, and a phosphor slurry liquid containing styrylpyridinium group pendant polyvinyl alcohol (PVA-sbq) and a phosphor whose body color is UV-absorbing is applied on the precoat layer to form a phosphor layer. Forming a phosphor layer in a desired pattern by irradiating ultraviolet rays through a photomask and performing wet development. Construction method.