Coating for a luminescent material
AssigneeKoninklijke Philips Electronics N.V.
InventorsThomas Jüstel, Jacqueline Merikhi, Hans Nikol, Cornelis R. Ronda
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Abstract
A metal M is chosen from the group formed by Y, Al and La, and a watery solution of a complex of M and an organic chelating agent is added to a suspension of luminescent material, which causes a layer of M2O3 to be deposited on the luminescent material, which is then separated, dried, and fired.
Claims9
Luminescent material coated with a layer comprising:
- a metal oxide, M2O3, in which a metal M is chosen from the group consisting of yttrium, aluminum and lanthanum,
- said layer being substantially free of M(OH)3 and comprising granular, spherical nanoparticles of the metal oxide, said nanoparticles having a diameter smaller than 30 nm.
A discharge lamp comprising a luminescent screen, said screen comprising a luminescent material with a coating of a metal oxide, M2O3, in which a metal M is chosen from the group consisting of yttrium, aluminum and lanthanum,
- the coating being substantially free of M(OH)3 and comprising granular, spherical nanoparticles of the metal oxide, said nanoparticles having a diameter smaller than 30 nm.
A discharge lamp comprising a luminescent material coated with a layer to form a coated luminescent material using precipitation from a watery solution containing a complex of a metal, an organic chelating agent and a suspension of said luminescent material,
- wherein said coated luminescent material is configured to have an enhanced light output and scattering compared to coating applied by chemical vapor deposition,
- wherein the coating layer comprises a metal oxide, M2O3, in which a metal M is chosen from the group consisting of yttrium, aluminum and lanthanum, and
- wherein the coating layer comprises granular, spherical nanoparticles of the metal oxide, said nanoparticles having a diameter smaller than 30 nm and being substantially free of M(OH)3.
A discharge lamp comprising a luminescent material coated with a layer to form a coated luminescent material using precipitation from a watery solution containing a complex of a metal, an organic chelating agent and a suspension of said luminescent material,
- wherein said coated luminescent material is configured to have an emission spectrum and a reflection coefficient which are substantially identical to that of the luminescent material without having said layer, while having a quantum efficiency for a 254 nm radiation which is higher than that of the luminescent material without having said layer,
- wherein the coating layer comprises a metal oxide, M2O3, in which a metal M is chosen from the group consisting of yttrium, aluminum and lanthanum, and
- wherein the coating layer comprises granular, spherical nanoparticles of the metal oxide, said nanoparticles having a diameter smaller than 30 nm and being substantially free of M(OH)3.
Dependencies are inferred from the claim text.