JPH05295587A - Production of shadow mask - Google Patents

Abstract

PURPOSE:To provide a method for continuously producing a shadow mask without deforing the mask. CONSTITUTION:The patterns of shadow masks are formed so that shadow masks are formed on the surface of a conductor in a noncontact state with each other, the conductor is electrplated to a desired thickness to obtain a plating film, the film and the conductor are peeled off, and the obtained film is used as a shadow mask. As a result, a shadow mask is continuously obtained without being deformed which has not ever been attained, and the production cost is drastically reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a shadow mask incorporated in a shadow mask type color image receiving tube.

[0002]

2. Description of the Related Art Some shadow masks incorporated in a shadow mask type color image receiving tube have a circular or rectangular electron beam passage hole. And the pitch of these holes is 6 in the shadow mask for general home color TV.
00 to 700 μm, 300 μm or less for high-definition television shadow masks.

Such a shadow mask has a thickness of 100 to
A mild steel plate of about 200 μm is cut into a predetermined size, a photoresist is applied to both surfaces of the obtained mild steel plate, and dried, a mask having a desired shape is brought into close contact, exposed, developed, dried, and then It is obtained by etching a mild steel sheet with an aqueous ferric chloride solution or the like and peeling off the resist layer. After that, in order to prevent irregular reflection of the electron beam irradiated on the shadow mask surface as necessary, and to minimize the temperature rise of the shadow mask when using the image receiving tube, the surface of the shadow mask is covered with iron tetroxide. Form a coating.

The shadow mask obtained by the above-mentioned etching method has already been used in a general domestic color television and put into practical use. However, the above-mentioned manufacturing method is a batch process, and there is a problem that productivity is lacking. In order to solve this problem, continuous striping of the resist layer using a long mild steel plate, and then a method of individually cutting by a press or the like has been studied, but in this method, shadowing is performed at the time of cutting by a press or the like. Another problem arises that the mask is deformed.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a shadow mask continuously and without deformation.

[0006]

As a result of various studies, the present inventors have found that the above problems can be solved by using a so-called electroforming method, and have completed the present invention. That is, the method of the present invention for solving the above-mentioned problem is to form a pattern of a shadow mask using a resist at intervals such that each shadow mask is formed without contact on the conductor surface, and then form a desired thickness. To obtain a plating film by electrolytic plating until
Then, the plated film and the conductor are separated, and the obtained plated film is used as a shadow mask, and the conductor is preferably a long conductor.

[0007]

In the present invention, since the shadow mask formed on the conductor is peeled off, it is not preferable that the conductor firmly adheres to the plated metal layer. However, the conductor is not limited to a special conductor such as a stainless plate having a passivation layer on the surface or an aluminum alloy plate passivated with chromic acid. This is because it is possible to obtain a metal layer that is easily separated from the conductor by controlling the plating conditions. In order to ensure continuous operation, which is one of the objects of the present invention, the steps may be combined using a conveyor or the like to be continuous, but it is more effective if the conductor itself is made long.

Further, the resist can be freely selected as long as it does not deform, dissolve, or peel off from the conductor during plating. The pattern of the shadow mask may be obtained by exposing and developing using a photoresist as a resist, for example, or may be obtained by a screen printing method, for example. However, the adjacent patterns must not touch. This is to ensure that the shadow mask can be individually recovered when it is separated from the conductor, and if it is not, a cutting process for individually collecting the shadow mask is required. This is because deformation occurs.

The method of separating the plating layer and the conductor is not particularly limited. For example, the conductor may be slightly bent to peel it off, or a jig such as a peeling machine may be used.
The method of the present invention can also be applied to the production of electronic parts such as lead frames and single-layer TAB produced by the etching method.

[0010]

EXAMPLES Examples of the present invention will be described below. (Example 1) A continuous shadow mask manufacturing apparatus in which a resist layer forming step, a pattern forming step, and a plating step are combined is used, and a width of 1 m and a length of 200 Negative photoresist PMER HC made by Tokyo Ohka Kogyo on the surface of a long stainless steel plate
-600 is evenly applied to a thickness of 45 μm, dried and then spread
296 50 μm, 574 mm long slits at 200 μm intervals
Masking was performed so that the patterns of eight 37-inch shadow masks were continuously formed at intervals of 10 mm, exposed with ultraviolet light having an intensity of 1000 mJ / cm ² , and then developed. Then, the exposed stainless steel surface is plated with electric iron under the following conditions to a thickness of 35 μm.
Of the plating film, and then the stainless steel plate was slightly warped to continuously separate the plating films obtained one by one. (Composition of plating solution) Ferrous chloride: 450 g / l Calcium chloride: 20 g / l (Plating conditions) Temperature: 90 ° C Cathode current density: 5 A / dm ² Anode: Platinum Plating time: 30 minutes After sticking the obtained plating film on the frame, it was heated in a mixed atmosphere of steam and carbon monoxide at 450 ° C for 30 minutes.
A good shadow mask of 5 μm could be obtained.

(Comparative Example 1) An electroplated film was obtained in the same manner as in Example 1 except that the patterns of the shadow masks were brought into contact with each other. After that, the stainless steel plate was slightly warped to separate the plating film from the stainless steel plate, and punching was performed by a press to separate the shadow masks.

[0012]

According to the method of the present invention, it is possible to continuously obtain a shadow mask, which has been difficult in the past, without deformation, and it is possible to greatly reduce the manufacturing cost.

Claims (2)

[Claims] 1. A pattern of shadow masks is formed using a resist at intervals such that the shadow masks are formed on the conductor surface without contacting each other, and then electrolytic plating is performed until a desired thickness is obtained. A method for producing a shadow mask, comprising: obtaining a plating film, then separating the plating film from a conductor, and using the obtained plating film as a shadow mask. 2. The method according to claim 1, wherein the conductor used is long.