LIGHT-ACCUMULATING LUMINOPHOR AND A METHOD FOR PREPARATION THEREOF Russian patent published in 2004 - IPC

FIELD: optical engineering.

SUBSTANCE: invention is dealing with optical and electronic appliances and can be used when manufacturing information storage systems. Light-accumulating luminophor has formula Mg_1-x-y-zSr_xEu2+y

Mn2+z(ΣTR)_pAl_qO₄, where ΣTR = Dy, Nd, Ce; x = 0.80-0.96; y 0.001-0.03; z = 0.005-0.010; p = 0.01-0.05; 1.99 ≤ q ≤ 2.05. Optimal ratio Dy₂O₃/Nd₂O₃/Ce₂O₃ varies between 1:1:1 and 6:3:1. When excited with ultraviolet light having wavelength no more than 365 nm, photoluminophor emits in green spectral region with dominant wavelength 525 nm. When emitting accumulated summary light, emission spectrum of luminophor shifts to short-wave region. Preparation of photoluminophor comprises primarily grinding mixture of strontium hydroxide, aluminum hydroxide, magnesium oxide, and manganese carbonate in stoichiometric proportions on vibrating mill during 0.5-1 h. Ground blend is impregnated with solutions of following activators: Eu(NO₃)₃, Dy(NO₃)₃,_{Nd(NO3)3, and Ce(NO3)3.Second grinding is effected for 2-6 h on vibrating mill to achieve specific surface above 24.0·10^-3 cm²/g. Reground blend is granulated, calcined for 0.5-2 h at 800-900^оС, and subjected to intermediate grinding on vibrating mill. Resulting material is thermally treated for 7-10 h in flow-type multizone furnace gradually raising temperature from 20^оС to 1330^оС in dissociating ammonia atmosphere at pressure 10 to 100 mm Hg, after which cooled in the last zone to 220^оС. Thus obtained luminophor has semi-diurnal emission cycle at high brightness level.}

EFFECT: enhanced luminescence efficiency, increased water and atmosphere resistance, eliminated abrasiveness if grains, and increased productivity of preparation process.

4 cl, 3 tbl