Hi all,

I have recently fallen in love with Diamine's Prussian Blue. It is extremely well behaved in my MB 145 and is of a lovely shade of blue. The only gripe I have is the lack of water resistance... a quick run under the tap and almost nothing remains. Because of this, and also to get a slightly darker shade of blue, I am thinking of mixing in some Diamine's Registrar's ink, which is iron-gall. Would there be any problems with this?

Thanks!



Paul

I've never heard of Diamine inks causing trouble in mixes, and I know most iron gall inks are mixtures of iron gall and regular fountain pen ink. I can't think of any problems. The standard precautions are to never let the pen go dry and to flush the pen out more often. Have fun!

You might try mixing the two inks in a glass or something and seeing what happens over a few days' time. Also, iron gall ink can cause problems in some pens as well as on some papers. You might also want to consider trying one of the Noodler's waterproof colors.

1) Mix the two and let it sit for a few days and see if anything precipitates out.

2) Flush your nib weekly and write something EVERY DAY with the pen to keep corrosion effects to a minimum.

3) If you run it under water you will probably rinse away everything that's not the iron gall ink, so substantial fade, but not a total wash out.

I'd say of all the mixing questions we get here, THIS ONE IS THE ONE MOST LIKELY TO HAVE ILL EFFECTS.

Registrar's Ink is acidic, has sulphates, and complexed metals present. Aniline or other dyes present in "normal ink" could undergo ligand exchange and result in odd precipitates or other reactions. I'd be very careful here and follow Ink Stained Wretches' recommendations.

Let us know how this turns out!

yes, this is what I am afraid of... the change in pH might result in some ions coming out of solution. Guess I will try with a small sample and see what happens.

I also have access to some filters/centrifuges, so I might try to remove any suspended particles. Will this cause any ill effects?

You could filter out stuff, but that doesn't necessary mean that the ink would then be stable, safe or useful. The act of filtering might provoke further reactions as you push L'Chartlier's Principle.

If you are looking for the quick and easy solution, just get Noodler's Prussian Blue. It is one of the bulletproof line and should meet your needs.

Thanks Chemyst.

Hmm I didn't know Le Chatelier's principle applies to suspended solids... looks like I gotta brush up on my chemistry.

I wish I could use Noodler's, but I swore off them after the last one I tried feathered, creeped all over my nib and looked quite chalky.

Maybe I'll just mix a small sample and see. I'm planning to mix in the range of 20:1 ratio, so I'm hoping the Registrar's wouln't be an issue here. Will let you know how it turns out.

According to Greg Clark's Fountain Pen Ink Sampler, Final Edition, most Diamine inks in the blue family have an acidic pH, so you're probably ok. While Prussian Blue itself isn't listed, their Blue-Black is, and it's pH is 5.0.

I've seen the Registrar's listed as 3.0

The pH is really a secondary concern though, the primary being that chemically these are very different inks. It isn't the same as mixing some blue and red Diamine together, it is more like mixing oil paints and watercolours.

Well, besides any obvious colour changes and sedimentation, are there any other things to look out for to decide if the mix is "safe"?

Is it ok to adjust the pH to 7.0?


Thanks.


Paul

Adjusting the pH will likely result in more sedimentation and loss of color. It is at a low pH to hold the dyes in solution, otherwise Diamine would have buffered it to 7.0 already. I doubt anything about this is "dangerous" per se, just likely to end up with a somewhat less usable product. Try it out.

How were you planning to adjust the pH BTW?

How I often do it with solutions in my biology lab... add Tris buffer (pH 6.6) or add NaOH.

Actually, I meant to ask how I could tell if the resulting mixture would be dangerous to my pen


Thanks!

Well, I think the main problem will be sedimentation either immediately or at a later time, which will clog your pen. The shift in pH may change some of the ions in solution into a state which would attack the metal or plastic components in your pen, but I think this rather unlikely. If you are concerned about it though, rinse your pen after a few days and do a thorough visual inspection. Alternately, you could immerse a junk pen of similar construction in your new ink.

Yep the Le Chatelier-Braun principle applies to equilibriums so taking out some of the precipitate could effect the equilibrium.

K

Yep the Le Chatelier-Braun principle applies to equilibriums so taking out some of the precipitate could effect the equilibrium.

K

Thanks guys. I juz received my Prussian Blue so I hope to let you know the results soon.

Paul.


PS: the Prussian Blue I got from Diamineinks.co.uk is of a slightly duller shade than the sample I received from Pear Tree Pens. Anyone got this experience?

Well, looks like all of you were right. I mixed a 20:1 ratio and there was sediment stuck to the bottom of the test tube.