Luminescent barium-hexa-aluminate, luminescent screen provided with such an aluminate and low-pressure mercury vapour discharge lamp provided with such a screen

摘要

Luminescent Eu2+ activated barium-hexa-aluminate mainly having the crystal structure of beta '-alumina and being defined by the formula (x-p)BaO.pEuO.(6-0.67x)Al2O3 in which 0.90/=x/=1.22 and 0.005/=p/=0.25 and in which 1 to 20 mol% of the BaO is replaced by at least one of the oxides CaO and 0.67Li2O.