Marker tips, often called nibs, are used in a variety of writing instruments to wick ink from a reservoir to the writing surface. The design and material used in manufacturing nibs depends on the type of ink and how the pen is to be used. All POREX® Nibs are designed to function in capillary systems using inks having viscosity and surface tensions similar to that of water.

Nibs can be made from polyvinylidene fluoride (PVDF) or polyethylenes (PE), depending on strength, ink flow, durability, and shape considerations. These PVDF and PE nibs have a “tortuous path” structure, which creates the ink flow channels. They can be processed to wick either solvent, alcohol or water based inks. They can also be used to wick fragrances, solvents, chemical reagents, and other liquids. Care must be taken in designing the total system since the liquid, reservoir, barrel, and nib all affect the final performance.