Light weight shadow mask and method of manufacturing

摘要

An aperture grill for a cathode ray tube is formed with parallel slits by etching a cold-rolled low-carbon steel plate from the opposite sides thereof. Before carrying out the etching, the steel plate is subjected to an annealing step whereby the residual stress is reduced to 7.0 Kg/mm2 or less. The steel plate is also subjected to a tensile force for imparting a tension in the direction of the rolling of a hoop steel from which the steel plate is produced. Furthermore, the steel plate is so oriented that the direction of tapes of the aperture grill to be produced will coincide with the rolling direction. The above process makes it possible to prevent occurrence of "streaks" and improves the quality of images generated on the cathode ray tube.