The Twilight Zone, The X-Files, or My Ignorance and Ignorance?!?

[Zorica Obradović]

The Twilight Zone, The X-Files, or My Ignorance and Ignorance?!?

I drew a drawing on cardboard with this pencil. When I laminated, the drawing disappeared. An empty cardboard remained. On the second postcard, I just wrote the address with this pen, and after the laminator it also disappeared.

Do you have an idea?

[Predrag Petrovic]

Erasable gel pen ink can disappear when scanned because
the heat generated during the scanning or photocopying process makes the thermo-sensitive ink turn transparent. The writing is still on the paper, but it is invisible to the scanner's optical system.
How Thermo-Sensitive Ink Works

Heat-Activated Disappearance: The ink in most modern erasable pens, such as the Pilot FriXion line, is "thermochromic". When the paper is rubbed with the pen's eraser tip, the friction creates heat, which causes the ink to become clear or invisible.