MANUFACTURE OF FLUORESCENT SURFACE AND CATHODE-RAY TUBE

PURPOSE:To form a fluorescent surface of excellent adhesive strength by forming a small granular phosphor having a specific central granular diameter, on a glass surface, and by forming a large granular phosphor having specific central granular diameter thereupon. CONSTITUTION:Two kinds of silver and aluminium activation zinc sulfide phosphors not shorter than 12 micrometer, or 14 micrometer in this example, and of central granular diameter of 5-8 micrometer, or 7 micrometer in this example, are prepared, and after the small granular phosphor of 7 micrometer is precipitated and applied on the glass surface of a cathode-ray tube, by a normal process, in such a way that the application density is 1.5mg/cm , a large granular phosphor of 14 micrometer is precipitated and applied in the same way so that the application density is approximately 4mg/cm , and a fluorescent surface is thus formed. A phosphor of central granular diameter of no less than 12 micrometer, which has excellent relative brightness, excellent gammacharacteristic and burning characteristic, can thus be obtained by a bonding process which is superior for the glass surface.