Manufacture of shadow mask for color picture tube

Abstract

Abstract PURPOSE: To realize the manufacturing process for the color picture tube shadow mask, with which the uneven diameter of the through-hole and dispersion are eliminated and with the reduced amount of the side etching. CONSTITUTION: The spray etching is given to the large hole side with application of the high-period microvibrations given to the metal plate to be corroded in order to secure the uniform stay of the etching solution on the metal plate to be used as the shadow mask for the color picture tube and also to secure smooth flow of the etching solution inside the hole. After this, the spray etching is given to the small hole side. In this way, the fluidity is enhanced for the etching solution on the metal plate as well as inside the hole owing to the mechanical micro-vibrations. Thus, the new etching solution is replaced on the etching surface at all times to shorten the etching time as well as to ensure the uniform distribution of the etching solution. As a result, the uniform etching is possible without any uneven diameters of the holes. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Yasuhisa Otake

Bibliographic Details