摘要 |
A single-component ARTIC BRITE(TM) phosphor and a low pressure discharge lamp utilizing such a phosphor is provided having a lamp envelope 3 having an inner surface 15, means 5,6,7,9,13 within the lamp envelope for generating ultraviolet radiation; and a layer 17 of a luminescent material adjacent the inner surface of the lamp envelope for generating visible light when impinged by the ultraviolet radiation. The phosphor material is at least one layer of a single-component ARTIC BRITE(TM) calcium, halophosphate phosphor having CIE color coordinates of X=346 and Y=359 and a CRI of at least 69, preferably a calcium halophosphate having the formula Ca5-x-ySbxMny(PO4)3ClzF1-x-z, wherein x is from about 0.032 to 0.037; y is from about 0.06 to 0.14; and z is about 0.025 to 0.05. The phosphor is derived from low cost, mined calcium carbonate, employing reactants in the following ratios: based on six phosphate atoms) about 0.142 manganese carbonate, about 0.904 calcium fluoride, about 0.146 ammonium chloride, and about 0.062 antimony oxide; is derived from a formulation that employs a high metals-to-phosphate ratio of about 9.890 to achieve a friable phosphor cake resulting in less fines formation with a number average particle size of 6.3 mum.
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