Application of X-ray diffraction technique for characterisation of pigments and control of paints quality

The importance of X-ray powder diffraction technique for the characterisation and standardisation of crystalline pigments used in paint industry is highlighted with 22 most commonly used commercial pigments and extenders. The need for generating an in-house library of diffraction patterns of various pigment samples and using these diffractograms along with corresponding lattice spacing (d) and relative intensity (I/I0) values for rapid identification and standardisation of unknown pigment samples from various sources or from paint samples is emphasized in this work. The limitation of this technique for characterisation of mixed phase samples is also discussed and the need for using other complementary techniques like EDX along with XRD technique is illustrated with an example.