電子写真用トナーの形態観察および組成解析 Morphological Research and Composition Analysis of Toner for Electrophotography
The information of particle size and dispersion of component of toner are obtained by Transmission Electron Microscopy (TEM) observation. TEM sample preparation most suitable for toner is ultramicrotomy. To distinguish toner from embedded resin, and avoid a change of toner in contacting with embedded resin, it is necessary to coat metal on the surface of toner before embedding. Wax which is contained in toner is able to be observed by RuO<sub>4</sub> staining. For the printed media, TEM or Optical Microscopy (OM) observations are also effective. In the composition analysis of toner, it is important to contrive the separation methods and to select the suitable analytical methods for each component. Especially, it is difficult to decide the chemical structure of the organic pigment. Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-MS) is one of the good methods to determine the molecular weight of the pigment especially phthalocyanine. The reductive decomposition of azo bond is efficient to transform the azo pigment to soluble compounds. The chemical structures of these compounds are determined by LC/MS and NMR, and the structure of the original pigment is constructed from these degradation products.
日本印刷学会誌 42(5), 273-278, 2005-10-30