INNER MAGNETIC SHIELD MATERIAL FOR CATHODE RAY TUBE AND PROCESS FOR PRODUCING THE SAME

摘要

An inner magnetic shield material for fabricating an inner magnetic shield to be disposed in a color cathode ray tube, which comprises a steel strip having at least one major surface thereof provided with a coating of organic resin composed essentially of C and H, or C, H and O, or C, H, O and N, and wherein the steel strip on its surface exhibits a surface roughness (Ra) of 0.2 to 3 mum and the thickness (T) of the organic resin coating is in the range of 0.1 to 6 mum. The ratio of T/Ra is preferably in the range of 0.2 to 4.0. The organic resin coating contains dispersed wax particles. The ratio (Phi/T) of wax average particle diameter (Phi) to coating thickness (T) is in the range of 0.5 to 5, and the content of wax in the coating is in the range of 2 to 20% in terms of the ratio of area occupied by wax when the coating surface is observed through an electron microscope. The organic resin coating may contain one or both of (a) a total of 2 to 50 mass% of at least one coupling agent and (b) a total of 2 to 80 mass% of at least one metal oxide selected from among SiO2, Fe3O4, Fe2O3, Ni-O, Zr-O, Cr2O3 and Al2O3.