The very popular ‘Frixion ball’ came to the world suggesting it was the world's first erasable ballpoint pen.

At the time when Pilot introduced this product to the world in 2007, it was hailed as sensational. However, this is not the beginning of erasable pen history. The very first erasable ball pens were actually invented by Mitubishi Pencil in Japan and Papermate in the US. Their products were the ‘Uni-ball Signo Erasable’ and the ‘Papermate Replay Max’.

Although the ‘Erasable’ function is the same, the trick to ‘erasing’ is completely different.

Whilst the Frixion ball uses a special ‘frixion ink’ that changes colour in different temperatures, the ‘Signo Erasable’ is using ‘erasable ink’ which can literally be ‘erased’ just like a pencil lead. The mechanism of the erasable ink is as follows:

1. Larger pigment – the average size of an ink pigment’s particle is usually small enough to be absorbed deep inside the paper (fibre) such that the ink can be said to be ‘fixed’ to the paper. The erasable ink has a larger size of pigment ‘s particle than that of average ball point pens. Due to these too large pigment’s particles, they are not soaking into the fibres; the ink stays on the surface of paper.

2. Transparent particles - The ink contains small transparent particles, which block the space that the larger ink droplets might be able to soak into.

3. Appropriate-levelled adhesion - the adhesion (fixing power) to paper has been carefully calculated, to make it possible to be erased only by an eraser, i.e. it won’t be erased just by rubbing with hands.