An improved coating having a high concentration of blue phosphor powder was made with a modified Triton X-100 dispersant. The barium magnesium aluminate phosphor was very well dispersed in terpineol if the Triton (octyl phenol ethoxylate) had terminal carboxylic acid groups, which had been added to the Triton molecule by chemical synthesis. This improved dispersion was screen-printed, dried, and then sintered. Because of the very tight packing of the phosphor particles, the photoluminescence intensity of the phosphor film in vacuum ultraviolet excitation was significantly increased up to 10.23%. (C) 2008 Wiley Periodicals, Inc.