JP2000231889A - Shadow mask plate material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the adhesion to a photoresist, enhance the adhesion to a negative pattern and increase quality and productivity by providing a specific surface roughness and the projection condition of the surface roughness on a shadow mask plate material used for a color picture tube. SOLUTION: In this shadow mask plate material, by limiting the surface roughness Ra of the shadow mask plate material and the projection condition Rsk of the surface roughness, the adhesion to a photoresist and the adhesion to a negative pattern are increased and the time of suction for the adhesion is reduced. The surface roughness Ra of the shadow mask plate material is 0.55-0.65 μm and the projection condition Rsk of the surface roughness is +0.7 or more. In this case, the projection condition Rsk of the surface roughness expresses the value of the relativity of an oscillation distribution curve with respect to an average line and is shown by the expression: Y(i) is a roughness curve when an average line is the X axis and the direction of vertical magnification is the Y axis in the reference length of a cross-sectional curve; Rq is square-average roughness; n=230; and j=2-5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for manufacturing a shadow mask used for a color picture tube, in which the adhesion between a metal material and a photoresist is improved, and the adhesion between a negative original plate is improved. The suction time can be shortened, the productivity can be improved, and the negative pattern can be accurately transferred. Furthermore, in the softening annealing process of the shadow mask in the color picture tube manufacturing process, the annealing adhesion The present invention relates to a shadow mask plate material that does not cause cracks.

[0002]

2. Description of the Related Art Conventionally, a low carbon aluminum killed cold rolled steel plate mainly composed of iron or an alloy mainly composed of iron and nickel, for example, a 36 nickel-iron amber alloy plate has been used as a shadow mask for a color picture tube. Have been. In these plate materials, there is no particular definition of the surface roughness.

[0003]

As described above, in the conventional plate material for a shadow mask, there is no clear definition of the surface roughness. Therefore, in the process of manufacturing a shadow mask from a plate material, a metal plate material and a photo plate are not used. The adhesiveness of the resist tends to be unstable, and the adhesiveness between the metal plate material coated with the photoresist and the negative pattern in the negative pattern transfer step is unstable. Furthermore, in the process of softening and annealing a shadow mask for providing deformability capable of being press-molded in a process of manufacturing a color picture tube, annealing and adhesion are caused, which adversely affects quality and productivity.

The present invention has been made in view of such a situation, and an object of the present invention is to stabilize adhesion with a photoresist and improve adhesion with a negative pattern in a shadow mask manufacturing process. It can improve quality and productivity, and has a surface shape that does not cause annealing adhesion in the softening and annealing process of the shadow mask in the color picture tube manufacturing process. To provide a shadow mask plate material.

[0005]

As a result of the research to achieve the above object, the present inventor has found that by regulating the surface roughness Ra and the projection state Rsk of the surface roughness of the shadow mask plate, the photoresist and The adhesion of the negative pattern is improved, the adhesion with the negative pattern is improved, the suction time for the adhesion is shortened, the productivity is improved, and the negative pattern can be transferred accurately, improving the quality. The present inventors have further found that in the softening and annealing step of the shadow mask in the color picture tube manufacturing process, it is possible to prevent annealing and adhesion, and based on such knowledge, the present invention has been completed.

That is, the plate material for shadow mask of the present invention solves the above-mentioned problems by regulating the surface roughness Ra and the projection state Rsk of the surface roughness of the plate material for shadow mask as follows. is there.

Ra: 0.55 to 0.65 μm Rsk: +0.7 or more Here, Ra is the surface roughness specified in JIS B0601, and Rsk is the relativity of the amplitude distribution curve to the average line. Is a value indicating the projection state represented by the following equation,

[0008]

(Equation 2) Y (i) represents the average line at X in the reference length of the sectional curve.
Axis, the roughness curve when the direction of the vertical magnification is the Y axis, Rq
Represents the root mean square roughness, n = 230, j = 2-5.

In this case, it is desirable that the plate material for the shadow mask is composed mainly of iron or mainly iron and nickel.

Hereinafter, each condition of the present invention will be described in detail.

As a result of the study, it has been found that the surface roughness Ra of the plate material for the shadow mask greatly affects the adhesiveness of the photoresist applied thereon and the adhesiveness with the negative pattern. If the adhesiveness of the photoresist is not appropriate, appropriate photosensitivity cannot be obtained, and the shape of the hole to be etched using the photoresist as a mask becomes non-uniform, thereby deteriorating the quality. Further, if the adhesion to the negative pattern is poor, the suction time for the adhesion becomes long and the productivity is reduced. Poor adhesion to the negative pattern means that the transfer of the negative pattern cannot be performed accurately, which is a factor that causes deterioration in quality. Therefore, as a result of research, it has been found that the surface roughness Ra specified in JIS B0601 needs to be specified as follows. That is, if the surface roughness Ra is smaller than 0.3 μm, the adhesion between the shadow mask plate material and the photoresist is too weak, so that a predetermined hole shape cannot be obtained uniformly, and the adhesion with the negative pattern also decreases. It worsens, causing a decrease in shadow mask quality. When the surface roughness Ra is larger than 0.8 μm, the roundness of the hole after hole formation is poor in the roundness, and the slot pattern is poor in the linearity of the slot. cause. For this reason, the surface roughness Ra needs to be specified to be 0.3 to 0.8 μm.

However, only by defining the surface roughness Ra, it is not possible to sufficiently improve the productivity in the shadow mask manufacturing process, that is, to shorten the suction time for the close contact in the negative pattern close contact process. It has been found that in the shadow mask softening and annealing process in the picture tube manufacturing process, it is not possible to prevent annealing adhesion. Therefore, as a result of various studies, it has been found that the definition of the projection state Rsk of the surface roughness is important. Rsk is a value indicating the relativity of the amplitude distribution curve to the average line 1 of the surface roughness shape within the reference length L, as shown in FIG. Rsk
Is +, which means that the roughness shape is upwardly convex as shown in FIG. 1A, which means that there are many protrusions. Conversely, the fact that Rsk is-means that there are many flat portions on the surface as shown in FIG. If there are many projections on the surface, a large number of air passages for suction are formed between the negative pattern and the plate material for the shadow mask in the negative pattern contact step, so that the suction time can be reduced. Furthermore, in the shadow mask softening and annealing step, the fact that the projections are present on the surface of the plate material for the shadow mask means that the contact between the plate materials becomes a point contact, thereby preventing annealing adhesion. For this reason, it turned out that the projection state Rsk of surface roughness needs to be +0.1 or more.

From the results of the investigations in the examples described later, the adhesion to the negative pattern, the accuracy of the transfer of the negative pattern,
In order to simultaneously satisfy the annealing adhesion preventing property, Ra is set to 0.1.
It was found that it is particularly preferable that Rsk is +0.7 or more in the range of 55 to 0.65 μm.

[0014]

Next, an embodiment of the present invention will be described.

As a shadow mask material, a low-carbon aluminum killed cold-rolled steel sheet containing iron as a main component and a 36 nickel-iron amber alloy containing iron and nickel as main components were used. These materials were rolled to a predetermined thickness, and the surface roughness Ra and the projection state Rsk of the surface roughness were adjusted by dull finishing. First, perform a degreasing treatment to remove rolling oil and rust-preventive oil, and then apply photoresist on both sides of the plate,
After drying, a negative pattern on which a predetermined dot-shaped or slot-shaped pattern was formed was brought into close contact, exposed, developed, and then subjected to a burning treatment. Thereafter, a predetermined hole was made by etching with a ferric chloride solution, and the remaining photoresist was removed to obtain a shadow mask. With respect to the shadow mask manufactured in this manner, the adhesiveness of the photoresist was compared with the peeling time of the photoresist from the plate material in 35% hydrochloric acid. The comparison was made. Further, the accuracy of the transfer of the negative pattern was compared and investigated with respect to the uneven quality of the shadow mask.

Next, in the color picture tube manufacturing process, softening annealing is performed in order to impart deformability capable of being press-molded. In this softening annealing process, the degree of adhesion by annealing was comparatively investigated.

The results of the above investigation are shown in Table 1 below. (Note) Unevenness grade: A Good with no unevenness B Good with almost no unevenness C There is a little unevenness but no problem in practical use D Unevenness and unusable E Very strong unevenness Annealing adhesion: a No adhesion b Outer circumference There is a little adhesion in the part. C A little adhesion is observed, but there is no effect on the workability (easy peeling). D It is difficult to peel off the adhesion and the workability is impaired. In Nos. 1 and 2, slight adhesion to annealing was observed, but there was no effect on workability and there was no practical problem. Examples 3 to 9 of the present invention have no problem with uneven quality and no problem with annealing adhesion. Particularly, Examples 6 to 8 of the present invention have no problem with uneven quality, have no annealing adhesion, and are excellent in the adhesiveness of a photoresist and the adhesiveness with a negative pattern, and a particularly good mask can be obtained. I have. From these results, Ra was 0.55 to 0.65 μm, R
It is understood that sk is particularly preferably equal to or more than +0.7.

On the other hand, Comparative Examples 10 to 15 have Ra,
Since one or both of Rsks are out of the specified range of the present invention, the quality of the unevenness is poor, and the workability due to the adhesion due to the annealing is exerted, which is not practical.

[0019]

As described above in detail, the use of the plate material for a shadow mask according to the present invention makes it possible to improve the productivity in the shadow mask manufacturing process and to manufacture a shadow mask having better uneven quality. Further, in the softening and annealing step of the shadow mask in the color picture tube manufacturing process, it is possible to provide a shadow mask which does not cause annealing adhesion and does not impair workability.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a projection state Rsk of surface roughness, and FIG.
(B) shows a roughness shape in which Rsk, whose projection state is convex upward, becomes +, and (b) shows an Rsk in which the surface has many flat portions.
Indicates a roughness shape where-is indicated.

[Explanation of symbols]

 L: Reference length l: Average line

Claims (1)

[Claims] A plate material for a shadow mask used for a color picture tube has a surface roughness Ra and a projection state R of the surface roughness described below.
Plate material for shadow mask characterized by having sk: Ra: 0.55 to 0.65 μm Rsk: +0.7 or more where Ra is the surface roughness specified in JIS B0601, and Rsk is the average line Is a value indicating the relativity of the amplitude distribution curve with respect to, and a projection state represented by the following equation: Y (i) represents the average line at X in the reference length of the sectional curve.
Rq represents a root-mean-square roughness, n = 230, and j = 2 to 5, when the direction of the axis and the vertical magnification is the Y axis.