Description Uni-ball signo 307 is the pen that uses a cellulose nanofibers first time in the world. It was very popular and got high evaluation with “SKIP FREE” in North America sold ahead. Uni-ball Signo uses new material fibre of the plant. The cellulose nanofiber is a very fine material that is uniformly mixed in the ink, was the ink viscosity at the time of writing able to reduce about 50% than the conventional gel ink ballpoint pen.
