We have 3 different kinds of ink in our collection, and all of them are document proof in varying degrees. Foremost, you have to be aware that the particles inside the ink which are responsible for creating the long-lasting effect can clog up the ink feeder (which is below the nib) or the ink tank, if the ink dries out.
The most resistant ink in our collection is Scribtol.
It provides good coverage and is light-fast as well as being non-fade, so this ink can be categorized as document-proof.
This ink should not be used inside fountain pens due to the mentioned reasons (color particles, i.e., soot). Instead, it should be used with drawing nibs only, i.e., those that don’t have feeding systems and are only dipped into the ink.
Pelikan's Indelible Ink!
A compromise is the Fount India. This ink is opaque and light resistant, i.e., it is also a document proof ink, with almost the same quality as Scribtol because it also contains soot, but in lower quantity than Scribtol ink. This ink can be used with piston fountain pens or with a converter in cartridge pens, too. The fountain pen must be rinsed with cold water regularly.
Carbon pigment is a component of the Fount India formula. As a result, this ink possesses almost the same level of light-fastness as our Scribtol ink.
What is important, however, is that the ink does not dry out or dry up completely in your fountain pen. To avoid this happening, you should regularly rinse out your fountain pen with cold water. Quality, made in Germany.
The ink Fount India is well-covering and non-fading, which makes it a permanent ink, particularly suitable for artworks and important documents to last for many years.
The ink 4001 in blue-black can be categorized as relatively lightfast. It is an iron gall ink, which means that it is far more permanent than, for example, the 4001 in Royal Blue or Brilliant Black.
Thanks to the special ingredients in the formula, it can be used in both piston and cartridge fountain pens. Over time, the color of the ink changes from blue-black to gray, though the ink will always remain visible.
The flow of ink and width of the nib determine the thickness of the stroke made on the paper. The absorbing capacity of the paper also determines how much ink can be applied. One factor that also plays a very decisive role is the amount of time that the ink has been exposed to the light for.
This ink is not document proof. We recommend Fount India to all customers seeking an ink that is even more permanent than our 4001 ink Blue black.
It is difficult to say how long these inks will last because it depends on a variety of criteria, for example how much ink flowed while writing (was it a slim line or a broad line); which kind of paper you used (how much ink did it soak up), and how many hours it was exposed to light. That’s why we can’t give a general answer to this question.