Hebei Messi Biology Co., Ltd. stated that in the formation of dielectric protective layer materials, in order to reduce the operating voltage of AC-type PDP and protect the dielectric layer from the influence of plasma generated in the discharge space, widely used materials with high secondary discharge coefficient and splash resistance are widely used. Magnesium oxide with excellent radioactivity.
AC-type PDP uses vapor-phase magnesium oxide single crystals generated by the vapor phase oxidation method with steam generated by heating magnesium, and the average particle diameter measured by the BET method is 500 angstroms or more, preferably 2000 angstroms or more to form an ultraviolet light emitting layer. The ultraviolet light emitting layer is formed on the surface of the discharge space side of the dielectric protective layer.
Hebei Messi Biology Co., Ltd. provides a magnesium oxide powder that is formed on the dielectric protective layer of gas discharge light-emitting devices such as AC-type PDP. When excited by ultraviolet light generated by gas discharge of xenon, it emits wavelengths with high efficiency. Ultraviolet light near 250nm.
High-purity magnesium oxide powder with a purity of 99.95 mass% or more and a BET specific surface area in the range of 5 to 150 m2/g, or magnesium compound powder (excluding magnesium chloride powder) that is calcined to produce the magnesium oxide powder, is prepared in the presence of a chlorine source By firing at a temperature above 850°C or in a chlorine-containing gas atmosphere, it is possible to produce magnesium oxide containing chlorine in the range of 0.005 to 10 mass%, with a purity of 99.8 mass% in the total amount except chlorine, and a BET ratio of A chlorine-containing magnesium oxide powder with a surface area in the range of 0.1 to 30 m2/g; and when the chlorine-containing magnesium oxide powder is excited by ultraviolet light generated by xenon discharge gas, it emits ultraviolet light with a wavelength near 250 nm with high efficiency, thereby completing invention.
Therefore, the present invention relates to a chlorine-containing magnesium oxide powder which contains chlorine in the range of 0.005 to 10 mass %, has a magnesium oxide purity of 99.8 mass % or more in the total amount excluding chlorine, and has a BET specific surface area of 0.1 ~30m2/g range.