Uniball 12-Piece Eye Fine Rollerball Pen Set, 0.7mm, UB-157, Black

Specifications: Uni-ball products are developed through technical expertise accumulated over the years include uni-ball water based ink roller balls with metal tips. The Uni-flow system ensures a continuous write with the same thickness to the very last drop of ink. Water Resistant: Dyestuff Ink is easily soluble in water and will bleed on the paper, uni super ink - pigmented ink will bond itself to the paper fibers once it is settled, it is not soluble in water. Light Resistant: The size of uni super ink particle is larger than dyestuff Ink. Therefore its surface is less affected and the colour remains vivid. Time Resistant: Difference between structure of molecules. Molecules of dye ink break down because of the sunlight and air but uni Super ink is difficult to break down.