Sakura Pigma Micron drawing pen. The first disposable technical pen to use archival pigment ink, the Micron range is favoured artists, writers and illustrators everywhere. PIGMA© ink has become the defining standard for reliable, permanent, archival quality ink. Archival quality ink is acid-free, chemically stable, waterproof, and fade resistant. No smears, feathers, or bleed-through on most papers. Strong plastic tip is steel clad for strength and for use against rulers and drawing instruments.