Which term describes ink that changes appearance with viewing angle?

Which term describes ink that changes appearance with viewing angle?

• A. Optically Variable Ink
• B. Magnetic Ink
• C. Invisible Ink
• D. Chemical Ink

Answer: (A)

The term describes ink that changes appearance with viewing angle is optically variable ink. This uses special pigments or coatings that shift color when you tilt the document, thanks to how light reflects off micro- or nano-scale structures. That angle-dependent color change makes authentication easier and is widely used on currency and other high-security documents. Magnetic ink relies on magnetic properties for machine reading (not color change). Invisible ink is hidden until a reveal method is applied. Chemical ink isn’t a standard term for this effect.

The term describes ink that changes appearance with viewing angle is optically variable ink. This uses special pigments or coatings that shift color when you tilt the document, thanks to how light reflects off micro- or nano-scale structures. That angle-dependent color change makes authentication easier and is widely used on currency and other high-security documents.

Magnetic ink relies on magnetic properties for machine reading (not color change). Invisible ink is hidden until a reveal method is applied. Chemical ink isn’t a standard term for this effect.