Why is it so much easier to iron a crease into a shirt than iron it out again?

Question

As title please

In: Physics

Answer 1

Because there’s no easy way to “invert” a crease in fabric. You can’t get flatter than flat.

When you iron the crease in, you’re folding the crease through 180 degrees. When you try to iron it out you’re opening both “legs” up 90 degrees to each side then trying to press it flat. So a lot more stress went into the bend to set the crease than you can put in to remove it.