Ferrimagnetic paper obtained by in situ synthesis of substituted ferrites

Abstract

A procedure for producing magnetic paper by in situ synthesis of substituted (Co, Ni) ferrites is described. Ferrites are formed in the presence of cellulose fibers and then forced to enter into the fiber lumen where they stay protected from mechanical influences. The remaining particles are washed out of the fibers leaving its external surface clean, so that its papermaking properties are not affected. Multilayer papers were prepared in which the colored magnetic layer is hidden behind white printable surfaces. Finally, the magnetic properties of the different kinds of obtained papers are compared with typical commercial standards, like subway tickets and airport boarding passes.