(CaO $\cdot$ Al$_2$O$_3$ $\cdot$ SiO$_2$): Eu phosphors for violet/ultraviolet-to-white radiation conversion

(2CaO $\cdot$ 0.5Al$_2$O$_3$ $\cdot$ 5SiO$_2$) : Eu and (CaO $\cdot$ 0.2Al$_2$O$_3$ $\cdot$ SiO$_2$) : Eu phosphors doped with B$_2$O$_3$ in an amount of 3 wt% are obtained by direct solid-phase synthesis at 1350$^\circ$C. When excited by LED radiation with a maximum at 380 nm, these phosphors emit white light with color coordinates, which are close to those in the EBU and NTSC TV standards and fall into the field of white light corresponding to light warning systems according to the International Commission on Illumination (CIE).