Working On The Perfect Prussian Blue Ink.

[Corona688]

I'm actually wondering if the pigment used in my beloved Sailor Sei Boku (nano particle blue black...Which is really deep blue occasionally leaning teal) is in fact the famous Prussian Blue.

Considering they also refer to it as Sailor Sei-Boku Nano Carbon Blue-Black, I'm now even more certain this isn't Prussian blue... The carbon is the nano part I guess.

[Tweel]

Someone may refer to Seiboku as "carbon" blue-black, but I don't think that Sailor does.

[Corona688]

Yesterday I tried sodium silicate as a surfactant/binder. Absolute failure: The pigment dissolves and disappears.

Looking it up, no wonder: Its as corrosive as lye.

According to this it's soluble in ethanol of all things, up to 10g/L. It's not a particulate ink if it's not particles! What about methanol or isoproponal I wonder.

Edited February 21, 2018 by Corona688

[Corona688]

Well that's interesting.

 

I wouldn't say prussian blue is soluble in methanol exactly. There's almost no bleeding when writing (with dip pen) in methanol-base prussian blue ink, even when I drip giant blobs onto the page. I don't think it's soluble in the sense of literally disassociating molecules.

 

It does do a terrific job keeping it suspended, however. Before, nothing but its sheer fineness slowed it down from falling through the water like a feather on the moon. Now it seems almost a part of the liquid. I wonder if this is what is meant by "turnbull's blue".

[Corona688]

This is what I get with 5 parts decanted Prussian Blue in water, and one part methanol:

 

http://burningsmell.org/images/i/prbl-methanol.jpg

 

I'm quite very happy with how consistent it is from start to finish and how well it sticks to the nib. Thin it much more and it stops holding as well.

[Corona688]

So, my 10-pack of Dollar 717i's finally arrived, and I have pens to destroy in testing.

 

It is possible to make Prussian Blue flow in a fountain pen! it involves significantly thinning it with 50/50 water and methanol. Under these conditions, it doesn't seem to clog readily. It is, however, not a very "wet" ink - both dilute and poorly-flowing. A pen with a very wet feed might do an acceptable job with it.

 

Without a wet feed, you'll write a line, wait for the feed to refill, write a line, etc, etc.

Edited March 15, 2018 by Corona688

[KellyMcJ]

Someone may refer to Seiboku as "carbon" blue-black, but I don't think that Sailor does.

Right...and there is no black in it, it's straight up incredibly permanent deep blue (and remarkably similar to all the photos of Prussian Blue that I can find.) There is no blue component that washes away leaving a permanent black like some inks...The nano pigment is definitely blue.

[Corona688]

Here's the problem: Consumer digital cameras and monitors have the color fidelity of a 1982 television broadcast. And I am speaking entirely literally there, that is the color range Microsoft and HP decided in 1997. Blues are especially problematic but most brightly colored inks can't be represented faithfully. Prussian Blue is one of these out-of-gamut colors. I literally can't show you what it really looks like. My camera can't record it and your screen can't show it anyway.

 

So until someone can put them side-by-side and compare with eyeballs, we just won't know.

Edited March 18, 2018 by Corona688

[KellyMcJ]

Here's the problem: Consumer digital cameras and monitors have the color fidelity of a 1982 television broadcast. And I am speaking entirely literally there, that is the color range Microsoft and HP decided in 1997. Blues are especially problematic but most brightly colored inks can't be represented faithfully. Prussian Blue is one of these out-of-gamut colors. I literally can't show you what it really looks like. My camera can't record it and your screen can't show it anyway.

 

So until someone can put them side-by-side and compare with eyeballs, we just won't know.

I actually have an old tin of Prussian Blue that was used for marking metal for machining...by my great grandfather! I could compare them side by side. Do you think it would have remained true to color after all these years?

[Corona688]

I actually have an old tin of Prussian Blue that was used for marking metal for machining...by my great grandfather! I could compare them side by side. Do you think it would have remained true to color after all these years?

Lucky! We still have perfectly good cyanotypes from 1910, so I bet it's fine. It doesn't age or photofade, though it can be bleached by very acidic paper. I'd love to see a comparison*, and maybe the can too.

 

*Yes, I know it wouldn't photograph faithfully, but might illustrate the difference if there is any.

Edited March 18, 2018 by Corona688

[KellyMcJ]

I am now as convinced as I could possibly be without doing a chemical analysis that Sei Boku is Prussian Blue.

 

 

 

 

It's an exact match in person- even closer I think than it looks in the photos (photos taken in natural light.)

[Corona688]

Fantastic. Thank you for that.

[KellyMcJ]

Fantastic. Thank you for that.

Your welcome! Thanks to my grandfather, or great grandfather. It was in the family heirloom toolbox.

[Corona688]

I wish I could find an MSDS for sailor nanopigment inks, they won't show the pigment but they'd probably illustrate the surfactant they used to keep it suspended.

[Corona688]

Narrowing in on the recipe of my favorite dip-pen ink. Made it once and am struggling to duplicate it, but getting closer. I've been mixing caplets on a 0.01g scale so this is all by weight, not volume.

 

By weight, 1500mg water, 400-500mg methanol, 10-50mg Prussian Blue powder, and an immeasurably minute yet vital micro-droplet of DOT3 brake fluid.

 

Use a little more brake fluid for very broad italics, etc.

Edited March 26, 2018 by Corona688

[Intensity]

I am now as convinced as I could possibly be without doing a chemical analysis that Sei Boku is Prussian Blue.

 

 

 

 

It's an exact match in person- even closer I think than it looks in the photos (photos taken in natural light.)

 

It was interesting to come to Sei-Boku in this discussion, as it was the ink I thought of too seeing all the examples of Prussian Blue. Sei-Boku is an interesting ink: it goes down as more vibrant higher teal component navy blue while wet and then dries quickly to a less vivid, less teal navy blue. It also sheens quite easily on non-absorbent paper in higher writing concentration. It can definitely look a lot like the stamp linked earlier. I would not call it a vibrant or "very deep and rich blue" that the OP was looking for, however, as while it is fairly saturated and can be deep, it lacks vibrancy of something like Diamine ASA Blue or Monteverde Charoite.

Edited March 31, 2018 by Intensity

[dcwaites]

I wish I could find an MSDS for sailor nanopigment inks, they won't show the pigment but they'd probably illustrate the surfactant they used to keep it suspended.

 

Surfactant won't keep a pigment suspended, brownian motion does. For that you need the pigment particles to be as small as possible, hence the nano-particle sizes.

 

The surfactant in the nano-particle inks would do what it does in any ink, keep it flowing through the very fine slot in the feed, and down the nib slit to the tip.

[Corona688]

Surfactant won't keep a pigment suspended, brownian motion does.

 

That's a deeply complicated subject. Surfactant isn't the right word, I'm now aware. It depends a lot on the surface properties of the particles, plus things like ionic attraction. The upshot is, it's definitely possible to make a colloid pretty stable! Maybe not for eternity but you can slow it down a lot. But without a degree in the subject I'm limited to trial and error.

 

Methanol certainly does a good enough job of keeping it suspended that I can't tell whether it's literally dissolving it - as some sources claim - or just keeping it suspended, as others claim. It certainly seems to defeat its tendency to clump, keeping it fine enough it can actually bleed just a little despite being a pigment ink.

Edited April 1, 2018 by Corona688

[Corona688]

I would not call it a vibrant or "very deep and rich blue" that the OP was looking for, however, as while it is fairly saturated and can be deep, it lacks vibrancy of something like Diamine ASA Blue or Monteverde Charoite.

We cannot be looking at the same color.

 

And really, we're probably not.

 

From colormaking attributes:

 

PB27 can achieve a beautifully saturated, very dark color in some preparations, but when used in watercolors its finished color is usually muted, greenish and moody. The masstone color is close to a reddish phthalo blue; it shifts very noticeably toward green in tints, and presents a similar large drying shift (lightening by 68% and dropping 20% in chroma), making this one of the most dynamic pigments available.

Further, it's very sensitive to method of preparation. By using a lot of excess ferrous iron (as would be done in printing and photography), I ended up with a weak, teal batch.

Edited April 1, 2018 by Corona688

[Intensity]

 

We cannot be looking at the same color.

 

And really, we're probably not.

 

From colormaking attributes:

 

 

Further, it's very sensitive to method of preparation. By using a lot of excess ferrous iron (as would be done in printing and photography), I ended up with a weak, teal batch.

 

I apologize, the way you quoted my post and replied to it is a bit ambiguous. Did you mean you and I are not looking at the same color, or you and the original poster, due to variations in formulation? I was referring specifically to Sailor's Sei Boku being an alternative as compared to the description the OP gave of his desired ink. Sei Boku is not a bland unsaturated shade, but neither is it a "rich" vibrant color that the OP wanted by description. Unless it was a misnomer and he meant that the color should be more vibrant than Diamine's Prussian Blue (in which case, Sei Boku is more vibrant). I always have a Kaweco pen filled with Sei Boku and use it regularly to sign checks and for general writing, so I'm very familiar with that ink. Looking at the samples you linked to, I think I understand now that perhaps Sei Boku IS what the OP is looking for.

Edited April 1, 2018 by Intensity