The following document is from KWZ to provide general advice on the use of their iron-gall based fountain pen inks.

About the use of KWZ Iron Gall inks

KWZ Ink iron-gall inks are so called "modern" Iron-Gall inks, they differ in to Iron-Gall inks that were prepared at the beginning of the twentieth century because KWZ iron-Gall inks are true solutions – they do not contain any suspended solids, nor do they incorporate strong mineral acids to stabilize ink (like muriatic acid or sulfuric acid for example).

Iron-Gall inks do require more care from the fountain pen user in comparison to standard inks. Please read the advice below on using Iron-Gall inks in fountain pens, these are especially important when using inks of this type in fountain pens with steel nibs.

Important note on using Iron Gall Inks in your pen - please read

It is recommended not to leave it unused for a long time in order not to let the ink dry out in the pen, otherwise it might be difficult to clean the pen. In the worst cases, this ink may damage your pen if left too long.

A pen filled with IG ink needs some special care, similar to when any permanent ink is used. The key here is not to let your pen dry out as this will leave a residue that can't be cleaned out. How long it can be left depends on your pen - a cheaper pen may dry out quicker but this is depends on your pen.  If IG inks are used on daily basis, there are no special requirements as the ink will not have dried out.

The Iron Gall series by KWZ Ink refers to the type of ink used in medieval times for writing manuscripts, but it has been designed as a modern fountain pen friendly ink. It is gaining popularity because the written notes are extremely long lasting on paper, as the color will darken over time as opposed to other inks, which tend to fade over time. Writing with it is fun, as the colour will change immediately. For example the pink ink becomes violet, the orange will become brown. The written notes are also water resistant to some extent. The dyes can be washed away, but the iron gall component is permanently bonded with the paper, so the text is still easy to read.

The range of Iron Gall KWZ Inks includes 3 types. IG Mandarin is light iron gall - it means that the iron gall component concentration is very low and the maintenance doesn't differ from using standard ink. IG Blue-Black is Archive Iron Gall, which means that the concentration of the iron gall component is very high, thus it is the most water resistant and the most permanent of the whole IG KWZ ink range.  All the other IG KWZ inks - blues, greens, violets, reds or brown are the medium type - iron component concentration is high enough to make the notes everlasting, but low enough to be highly convenient in daily use. We still recommend taking precaution when using any IG ink as we don't want you to damage your pen.

Iron Gall ink should not be left in a pen unused for long periods of time. If the ink is allowed to dry out in your pen it will be difficult to clean out and in the worse case the pen could be damaged if left for too long.

It should be noted that in case of leaving Iron Gall ink in an unused pen for a very long period of time, and depending on its drying out on many factors, it is possible for the corrosion of stainless steel nibs to occur. Nibs made of for example gold, titanium, palladium, platinum, silver, etc. are generally resistant to corrosion.

Iron Gall inks are waterproof inks and require compliance with a number of recommendations, following these guidelines will protect prevent any problems that might occur during the use of Iron Gall inks in fountain pens.

Well stored Iron Gall inks are a true solution, there is no solid residue suspended the ink. Only after application of Iron Gall ink on a substrate (ideally paper) and after evaporation of most of the water does the reaction occur which produces the water-insoluble complexes of iron with an intense dark colour.

• The same reactions which are responsible for darkening and formation of insoluble in water complexes of iron are also unfortunately possible in the interior of fountain pen. This can happen in case if fountain pen is left unused for long time or if fountain pen has large tendency to fast drying out. Cleaning dried Iron Gall ink is not especially difficult, but it requires a lot of time and patience (especially if you cannot or do not want to disassemble the pen). Iron Gall inks should be used in fountain pens that are in use regularly.

• Do not use Iron Gall inks in pens that tend to dry out when you leave them for relatively short periods of time. It is normal that if a fountain pen is left, for a week or two, at beginning of writing it requires a bit of pressure or writes a little darker.  However, if the pen has a tendancy to dry after a day or two without use it is best not to use Iron Gall inks in these pens.

• If Iron Gall ink forms deposits of solid on the walls and bottom of bottle then it should not be used in fountain pen. Spontaneous formation of sludge in Iron Gall inks is caused by improper handling, contamination or by the not appropriate proportions of ingredients used in ink. Also inks that are not Iron Gall, but have a tendency to spontaneous formation of deposits in the inkwell should be used with caution.

• Before inking with Iron Gall ink thoroughly wash your fountain pen – especially if other types of waterproof inks were used in particular pen. Similarly, if you change inks from Iron Gall ink to a different type of waterproof ink you should wash your pen through thoroughly. Iron Gall inks can interact with certain inks, which will result in the formation of difficult to remove sediment in fountain pen. Here are a few methods of cleaning from best to worst:

1. Disassemble fountain pen and wash it under running water or better in an ultrasonic cleaner with a bit of detergent, and assemble the pen after it was dried.

2. Rinse fountain pen with water with detergent, after that fill the pen with water with detergent. Then, leave the pen with the nib to the bottom touching tissue or other absorbing material so the water slowly flows through the pen. After that rinse pen with clean water few times.

3. Any other methods which rely on a simple rinsing the fountain pen, even if after rinsing, it seems that the pen is clean because water flashed out of pen – it only seems so. In the feed and canals in pen there is certainly a left some residues of ink. You can check it by filling the pen with water and leaving it for a day – I’m quite certain that water flushed out of pen will have some colour.

4. Changing ink in fountain pen without washing is not recommended and everyone who does it do so at his own risk. Different inks have different properties, and mixtures of inks may not wish to work together by creating difficult to remove the precipitate.

• If Iron Gall ink is left in unused fountain pen for long time, and it partially dried out, it should not be returned to the inkwell with ink – in this case, pen should be rinsed with water like before changing the ink. Returning old Iron Gall ink back into the bottle will reduce the stability of the ink that still remained in the inkwell. Iron Gall inks require stabilization to prevent them from premature formation of sludge and secure pen with metal parts in contact with the ink (eg. Nib) against corrosion. We use a set of several compounds with different action – thanks to the synergy between them we are able to achieve very good results while maintaining relatively not large concentrations of any of them. But stabilizing system can not run forever and ink left in the pen, which has free access to air and oxygen slowly undergoes degradation processes and compounds that stabilized ink lose efficiency. Returning old ink to the bottle will have a negative impact on the stability of such ink and may cause that formation of sediment in the inkwell.

• Produced by us Iron Gall inks will not cause corrosion in normal use in fountain pens with nib made of stainless steel or gold. But there are sometimes some nib pens made of ordinary steel, sometimes the nib is protected against corrosion, for example by passivation layer (usually chromium). With this type of nib, it is possible for corrosion, especially if the passivation layer is mechanically damaged. Most species of stainless steels will interact very little or with magnetic field – if the nib is attracted by a magnet, than with a high degree of certainty it can be concluded that it was not made of stainless steel or the steel was not properly processed.

• Iron Gall inks should be stored in a cool and dark place to protect them from the negative effects of light on their stability.

• Iron Gall inks should not be diluted with water from the tap – the water is rich in various salts and contains trace amounts of the compounds used for the decontamination of water (such as ozone, chlorine, etc.), those compounds will have negative effect on stability of ink. If we want to dilute Iron Gall ink distilled, demineralised water or boiled over water should be used.

• Past experience has shown that most of Iron Gall inks produced by me can be mixed with standard inks of my production, as well as some other manufacturers. In preparing mixtures of any inks adequate caution should always be taken. Most of red, brown and purple inks should not be mixes with Iron Gall inks.

It sometimes happen that after Iron Gall ink dries in fountain pen a residue of insoluble sediment might be left in pen. There are several methods that allow us to remove this residue of  Iron Gall inks from inside the pen:

• Rinse with water pen dish-washing liquid – a good solution to rinse the pen should be prepared by adding at least 2-3 ml of dish-washing liquid to 10-15 ml of water. This solution has a very low surface tension and easily penetrates all small nooks and crannies inside fountain pen. Rinse the pen with this mixture several times, then leave the pen for a few minutes and than rinse again. After that rinse the pen till there is no detergent in pen. Using ultrasonic cleaner ease up cleaning process. This method of rinsing can also be useful also for the cleaning pen residues from other inks.

• Vitamin C (ascorbic acid), – if the rinsing with solution of dish-washing liquid did not give satisfactory results, adding to the water with dish-washing liquid ascorbic acid (which may for example come from crushed tablets) and rinsing the pen with this solution several times, should remove any residues of Iron Gall inks from fountain pen.

• Many people use for cleaning fountain pens vinegar, ammonia solutions or ammonium acetate. I didn’t used those methods so I can not tell if they are effective or not, but rinsing fountain pen with ammonia water may have negative effect on materials in fountain pens.

• If there is a possibility, very good results will give washing disassembled fountain pen in an ultrasonic cleaner – it is worth adding a few drops of dish-washing  liquid to water.