Permanent Marker: Ink, Moulded Barrel, Reservoir and Nib

A marker is a moulded plastic barrel holding a reservoir of ink that feeds a porous nib. Permanent marker ink is a carrier solvent, usually alcohol-based, with a colorant and a resin (plus a glyceride and a pyrrolidone in one patented recipe), which makes the mark water-resistant. The barrel, cap and end plugs are injection-moulded. The reservoir is a polyester cylinder; nibs are compressed synthetic fibre or porous ceramic. One machine puts the reservoir in the barrel, fills it with ink, and fits the nib and the cap.