How Are Felt-tip Markers Made and How Do They Work?
A felt-tip marker is a pen which has its own ink-source, and a tip made of porous, pressed fibers such as felt. Inside a felt-tip marker is a wick-like filling soaked with fast-drying ink. The ink flows to the tip of the marker as you write.
First, the separate parts of the marker are manufactured. Marker bodies are molded from plastic. Strands of a soft material called polyester are fed into a machine that forms the marker tips. Then a single machine puts all the parts together.
After the tip and the filling are pushed into the body of the pen, a needle shoots ink into the filling. Finally, the machine attaches a back plug to seal up the marker, and then it presses on a cap.
There are two types of tips in felt tip markers. One is a thin, plastic nib that is usually housed in a metal funnel. These are very firm and dispense ink evenly and smoothly.
The other is a spongy, fibrous tip, usually shaped like a cone. They are more prone to losing their firmness over time, but their shape allows for more versatility. You can use the top of the tip to write finely, or turn it on its side to shade or color.