Abstract: A method is provided whereby high brightness metaborate phosphors are made by milling the reactants in a saturated aqueous solution of magnesia and boric acid prior to firing. The method increases the homogeneity of the fired metaborate phosphor cake and reduces the tendency of the fired cake to stick to the firing boats.

Abstract: A europium activated strontium tetraborate UV emitting phosphor is disclosed having a weight composition of from about 34.72% to about 35.80 strontium %, from about 17.66% to about 17.78 boron %, from about 0.37% to about 1.86% europium, and the balance oxygen. The phosphor has essentially elongated prism-like particles with the europium relatively uniformly distributed throughout the balance of the phosphor and with the particle size distribution being characterized by the 50% size being in the range of from about 7 micrometers to about 12 micrometers as determined by Coulter Counter measurement and with less than about 12% by weight of the particles having a particle size of greater than about 16 micrometers as determined by Coulter Counter measurement. The process for making the phosphor is disclosed which involves forming a mixture of strontium carbonate and europium carbonate in an aqueous solution of boric acid at a temperature of at least about 70.degree. C. with the mole ratio of SrCO.sub.3 to H.sub.

Abstract: A europium activated strontium tetraborate UV emitting phosphor is disclosed having a weight composition of from about 34.72% to about 35.80 strontium %, from about 17.66% to about 17.78 boron %, from about 0.37% to about 1.86% europium, and the balance oxygen. The phosphor has essentially elongated prism-like particles with the europium relatively uniformly distributed throughout the balance of the phosphor and with the particle size distribution being characterized by the 50% size being in the range of from about 7 micrometers to about 12 micrometers as determined by Coulter Counter measurement and with less than about 12% by weight of the particles having a particle size of greater than about 16 micrometers as determined by Coulter Counter measurement. The process for making the phosphor is disclosed which involves forming a mixture of strontium oxide and europium carbonate in an aqueous solution of boric acid at a temperature of at least about 70.degree. C. with the mole ratio of SrCO.sub.3 to H.sub.3 BO.

Abstract: A process is disclosed for producing a europium activated strontium borate phosphor having a strontium containing coating. The process involves washing a europium activated strontium borate phosphor with a solution of strontium hydroxide to produce a first washed phosphor followed by removing the first washed phosphor from the resulting wash solution. The first washed phosphor is washed with a wash solution selected from the group consisting of ammonium fluoride in alcohol, ammonium bifluoride in alcohol, and a strontium salt in ammonium hydroxide, followed by removing the resulting second washed phosphor from the resulting wash solution. The second washed phosphor is then heated to produce the coated phosphor.