Rollerball or ballpoint, same thing right, is there a difference? The answer, yes. Ballpoint and rollerball pens share a lot of similarities both use a “biro”. A biro is a tiny metal ball, usually 0.5 or 0.7 mm diameter, which transfers the ink from the reservoir onto the paper and allows you to write. This is where the two pens get their names.
Another shared trait is the cap, ah! But there is a difference with this. A ballpoint pen doesn‘t require a cap; the cap is simple there to protect the nib (writing tip of the pen) but it is not a needed item, click pens are example of this. Rollerballs however require a cap. If a rollerball doesn’t have its cap on (while not in use) it exposed and may suffer two risks, drying out and leaking. The reason for this is the ink, which is the major difference between the two.
A rollerball uses a water-based liquid or gel ink, as opposed to viscous oil-based ink found in ballpoint pens. Without the cap the less viscous ink will tend to dry out and/or bleed easier. This less viscous ink allows the ink the ability to flow smoother; thus giving rollerball pens their distinctive fluid writing feeling and quality. Now the ballpoint is not a second runner up. The ink used in ballpoints allows for it to right on different types of surfaces without issue and it doesn’t suffer the issues that the rollerball has, like possible smearing, making it a well-rounded pen.
As pen technology grows the differences between the two pens grows smaller and smaller. I have started to see rollerball click pens and ballpoint pens that write just as smooth and beautifully as a rollerball. Maybe one day they will be one in the same pen and we will call them what some countries refer to them, “ball pens”.