Energy and resource saving raw materials for dactyloscopy

Abstract

The “developing” properties of ferromagnetic fingerprint powders are defined by the chemical nature and the particle sizes of the pigment which form acidity of its surface, adhesive and magnetic properties, and color spectrum. The optimum ratio of these physical and chemical parameters is observed in the pigment consisting of iron-containing sludge tempered at 800°C, which contains α-Fe2O3 and impurity of clay materials.