The system has been developed for the mesurement and stability control of properties of hard magnetic inks (coercivity higher than 100 Oersted) during banknote printing process.
The system is based on the analisys of residual magnetism; the following parameters can be estimated by comparison with a reference ink or tape (3M 777), see figure:

• Hm : ink saturation magnetic field
• Br : ink remanent magnetic field
• Hc : ink coercitive field