Blue side of the eraser: we reveal the secret

Everyone knows the eraser with the red and blue sides. But hardly anyone knows what the blue side is actually good for. We’ll tell you what the cool trick is behind the two colours.

What is the blue side of the eraser for?

The blue side of the eraser is rougher and harder than the red side. But what exactly is it all about?

• When I was at school, there was always a rumour that the blue side could erase ink. However, it could not really be proven or explained.
• What the pupils always suspected is actually true: The blue end of the eraser is supposed to remove ink. The reason for this is a special composition.

How does the blue side of the eraser work?

How the sides of the eraser differ:

• When you write with a pencil on paper, small pieces of graphite stick to the paper. This happens due to the so-called “adhesion force”. However, the red side of the eraser creates a greater adhesion force so that the graphite comes off the paper.

• The blue side of the eraser is made of the same material as the red side. However, finely ground glass, quartz or pumice stone is added. Since the ink penetrates the paper properly, it cannot be removed from the surface. The blue part of the eraser therefore removes whole layers from the paper, thus damaging it.