METHOD FOR PRODUCTION OF FINELY-DISPERSED RED LUMINESCENT MATERIAL FOR GENERATION OF RESULTING WHITE LIGHT IN LIGHT EMITTING DIODES Russian patent published in 2018 - IPC C09K11/79 C09K11/80 F21S13/00 F21Y115/10 

FIELD: chemistry.

SUBSTANCE: in a vacuum-gas glove box the original dry powders are mixed with multiple sifting in a neutral atmosphere: calcium nitride Ca₃N₂, strontium nitride Sr₃N₂, aluminum nitride AlN, silicon nitride Si₃N₄ and europium fluoride in a stoichiometric ratio to obtain a composition with the general formula Ca_1-xySr_xEu_yAlSiN₃, where x=0.68-0.97; y=0.0009-0.027. To the resulting mixture, ammonium chloride and barium fluoride are added in excess of the stoichiometry in an amount of 3-5 wt % of the total batch weight at a 1:1 ratio. The powders mixture is then charged into an alundum crucible, placed in a vacuum oven, and sintered in former gas at a temperature of 1700°C with a heating rate of 4-5°C per minute. It is kept for 3 hours at 1700°C. The average particle size of the resulting phosphor is 7-11 microns, the monodispersity coefficient is 0.8-0.9. The intensity of luminescence at a wavelength of exciting radiation of 450-460 nm is 95-97%.

EFFECT: increase glow intensity.

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