Eli5 Pen “over” engineering

Question

Does anyone know how uniball pens work? Why do they have that clear filter thing? It looks cool and higher tech than other pens but is there an actual functional benefit?

In: 0

Answer 1

That isn’t a filter but an ink buffer. Ink is pulled to the tip through capillary forces. That structure basically stores ink so you can write a clear line even after not using the pen for a while.