Writing from an erasable pen disappears when exposed to heat.
Tips
usage
Onomatopoeic — 擦擦 mimics the rubbing sound of erasing. Most often refers to the Japanese Pilot FriXion (摩磨擦 mómócā) line, where friction-generated heat makes the thermosensitive ink vanish. Don't store filled-in test papers in a hot car.
mistakes
Don't confuse with 修正笔 (xiūzhèngbǐ, 'correction pen / white-out pen'). 修正笔 covers ink with white liquid; 擦擦笔 makes its own ink disappear by friction or heat.
