Optically Variable Color-changing Inks
Color changing inks are inks containing pearlescent pigments that change color when viewed at a different angle. The color of the ink does not actually change, but the angle of the light to the viewer's eye changes and thus creates the change in color. A number of types are available, including green to purple, gold to green and green to lilac.
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Famous quotes containing the word variable:
“Walked forth to ease my pain
Along the shore of silver streaming Thames,
Whose rutty bank, the which his river hems,
Was painted all with variable flowers,”
—Edmund Spenser (1552?–1599)