A guide to waterproof inks
Pigment Inks
See our De Atramentis Document Ink range.
Pigment inks contain tiny particles of pigment, which are not water-soluble and will then cling to the surface of the paper rather than sinking into the fibres. This means they are more likely to be waterproof than regular dye-based fountain pen ink – fantastic for artists and those who need their writing to hold up to water.
The downside of pigment inks is that the particles can clog up your fountain pen, resulting in flow issues and a generally 'gunked up' pen. When left like this for a long time, this can ruin your pen. Even if your pen can be rescued, there may be some long-term damage that can make it less enjoyable to use. (Note from author: I nearly ruined my beloved gold nib Pilot Vanishing Point by leaving De Atramentis Document Black in it for several months without using or cleaning it. Learn from my mistake!)
As a result, it's important to maintain a regular pen-cleaning regimen when using a pigment ink. There are numerous guides on the internet, but this one from JetPens is a good start.
Many people will argue about how frequently you should clean your pen, and our stance on this matter is that it depends on far too many factors for there to be a conclusive answer that will work for every pen, ink, and climate. When using pigment inks, however, we suggest a minimum of once a month and potentially as often as once a fortnight.
We do not suggest that beginners to fountain pens load pigment inks into their most expensive pens, however, regardless of cleaning regimen!
Iron Gall Inks
See our 'iron gall inks' selection.
For hundreds – if not thousands – of years, ink was made using oak gall. (If you're anything like me, this may be the point that you go down a YouTube and Wikipedia rabbit hole.)
Iron gall ink does still exist today, but it's far less popular than it used to be...for good reason! Iron gall ink is mildly acidic and, over time, can corrode a stainless steel nib. Whilst a gold nib is perfectly safe from iron gall ink, any stainless steel parts inside your pen – such as the plunger on a vac or piston fill – are at risk.
The way that iron gall ink works is that the water evaporates on the paper, and the exposed ferrous tannate complex reacts with oxygen in the air, turning into a ferric tannate. This is why iron gall inks all have that distinctive feature of darkening and colour-changing on the page as you watch. The result is water-resistant writing that will truly stand the test of time – 'archival' inks such as Diamine Registrars ink is iron gall for a reason.
The same oxidisation that happens on the page can, unfortunately, also happen inside your pen and in the ink bottle...leaving you with particles of iron rattling around and clogging up your pen. Far from ideal, to say the least.
You should therefore only use iron gall ink in pens that are either wholly disposable or ones that you use on a regular (e.g. daily) basis. If your pen has a poor seal or has a dry start after not being used for only a couple of days – you should avoid iron gall ink in it altogether.
Pens should be thoroughly cleaned before and after use with an iron gall ink, and under absolutely no circumstances should you mix an iron gall ink with another type of ink. That is how you get a nightmare sludge inside your pen!
Vanness Pens has an excellent article on KWZ IG inks in particular, which I recommend to anyone intending to use them.
