50ml glass bottle of Rohrer & Klingner Dokumentus Ink, Dark Blue Dokumentus is the world’s first fountain pen ink conforming to the resistance requirements of DIN ISO 12757-2. It has been tested by the „Papiertechnische Stiftung Heidenau“ (Paper Technology Foundation in Heidenau), an independent standards body which has certified that this ink can be used by registrars for official documents. New technology and high quality raw materials used to formulate this new pH-adjusted ink guarantees permanent and archival writing. Comfort of writing with a fountain pen was the main focus of this new product development. Do make sure to replace the cap on your fountain pen after use to prevent blockages in the nib. Beyond this no special care is needed!
