Optically Variable Ink with Polarizing Effect
A semi-transparent optically variable ink containing liquid crystal pigments with polarizing properties. When viewed from different angles in white light the image usually printed by offset and covered with the ink changes colour (fig. 1). The polarizing properties are checked through a special polarizing filter consisting of two windows – the colour of the image differs (fig. 1).
a
b
c
Fig. 1. Optically variable ink with polarizing effect. 50 000 Armenian Drams (2001):
a – without tilting; b – tilted; c – view through a polarizing filter