Effects of two cellulose binders on the luminous properties of phosphor pastes

Two cellulose binders (ethylcellulose and nitrocellulose) were used to fabricate white-colored phosphor pastes prepared from the mixture of Y2O3:Eu (red), LaPO4:Ce, Tb (green) and BaMgAl10O17:Eu (blue) for flat fluorescent lamps. The chemical composition of ethylcellulose and nitrocellulose vehicles was investigated by GPC (gel permeation chromatography) and FT-IR (Fourier transformation infrared spectroscopy) analysis, respectively, and the thermal properties of the binders were determined by TGA (thermogravimetric analysis) and DTA (differential thermal analysis). In addition, the residual carbon content of phosphor pastes calcined at 520 °C was measured by CS (carbon–sulfur determinator) analysis. After calcination at 400 °C, the residual carbon content of phosphor pastes fabricated from ethylcellulose and nitrocellulose was approximately 0.055 wt% and 0.028 wt%, respectively. The phosphor paste synthesized with nitrocellulose showed superior adhesion behavior, low residual carbon content and excellent luminescent properties.