Characterisation of Pigment particles by Scanning Electron Microscope and Image Analysis Programs

摘要

The size of the pigment particles can be measured by different analysers which can be based e.g. on sedimentation, laser diffraction or changes in electric field. However, also particle shape has great influence on paper properties, but there hasn't been any proper measuring method to evaluate that. In this paper, particle properties are examined by scanning electron microscope (SEM) and image analysis programs in order to measure also particle shape. The same pigments were also analysed by sedimentation and laser diffraction; and the results were compared to perceive the effect of the particle shape on the performance of the analysers. In contrast to other particle analysers, SEM coupled with image analysis program can calculate several particle parameters such as length, breath, aspect ratio, roundness etc. and chemical classification is also possible. And also 3D modelling is possible with a certain program. Particle analysis can be made at the same time when particles are visualised and imaged by SEM. However, a pigment sample has to be prepared carefully in order to be analysed with image analysis program. Thus, this research was divided into two parts: sample preparation and particle characterisation.