What’s the difference between gel, rollerball, and ballpoint pens?


What is the difference between the mechanism of each pen?

In: Engineering

Ball Points use oil based inks which are stickiest.

Roller balls come in 2 types:

Gel Rollerball – medium stickiness.

Water based Rollerball – least sticky.

Mechanically they have the same design at the tip, varied for the viscosity of the ink base (oil, gel, or water).

Edit: Some water based roller balls are so “runny” they have a section between the reservoir and the tip which slows the ink flow to stop it from spilling out. This section uses capillary action and vanes similar to modern fountain pens.