Effects of heat treatment on the charging characteristics of a quaternary ammonium charge control additive

Heat-treatment effects of a typical charge control additive (CCA), tributylbenzyl-ammonium 1-naphthol-4-sulfonate (TNS), were examined by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), isothermal charge decay and thermally stimulated current (TSC) methods. DSC themograms of TNS show two endothermic bands, a small band at 162°C and a large band corresponding to melting of TNS at 187°C. When TNS was heated above the temperature of the small DSC band, this CCA changed in its WAXD, DSC, TSC and isothermal charge decay characteristics. From difference in TSC characteristics of the CCA and model toners containing the CCA, TNS was confirmed to be more effective for tribo-charging than for corona charging. Coexistence of positive and negative charges in tribo-charged model toners was also suggested from the TSC results.