To provide an amorphous frit for CRT (cathode-ray tube) which is suitable for the sealing of a CRT bulb obtained by using a surface- strengthened planar panel, and has no cracks even if the CRT bulb is reheated in an exhaust stage after sealing.
The frit consists of amorphous glass powder and refractory filler powder, and an abnormal expansion in the range from a frit (glass) transition point Tg to a frit yield point Tf is <0.08%. In particular, the one obtained by mixing the amorphous glass powder and the refractory filler powder in the range of 95:5 to 59:41 by volume ratio, and in which the amorphous glass powder has a composition consisting of, by weight, 65 to 80% PbO, 3 to 8% B2O3, 2 to 8% ZnO, 0.1 to 3% SiO2, 0 to 3% Al2O3, 5 to 18% Bi2O3 and 0.5 to 4% Fe2O3+CuO is suitable.
HAYASHI MASAAKI
SHINDO KAZUYOSHI
