Thermogravimetric Analysis of Laser Printer Toner

Weight-loss on heating of 21 samples taken from different grades of toners used in laser printers was studied by thermogravimetry. A comparative study on the stability to heating and differences among the pyrolytic curves of these samples was made by analyzing these sample with the TA 2050 Thermogravimetric Analyzer under the conditions of static constant temperature and dynamic temperature elevation. In the whole process under the static constant temperature condition, the values of weight-loss of the 21 samples attained to values in the range of 0.60%-1.16% with the majority around 1%. While under the dynamic temperature elevation condition, significant differences were found among the data of weight-loss and the pyrolytic curves of these sample, shown especially by the number of steps appeared in the curves; the differences of temperature and temperature range relating to weight-loss and the differences of temperature attaining to constant weight as well as the masses of the respective residues. Based on these facts, discrimination among different brands of the toners and also a preliminary determination of their components could be made.