Does the acidity of the paper affect the likely fade rate of some inks?

[arcfide]

I've been wondering about this for some time, and I can't find any direct confirmations one way or another on this one. 

 

Inks have a variety of "stable" pH's at which they were designed to operate. We have plenty of cases of people writing with what would have been considered "fade prone" inks that have stood the test of time in closed, stable environments (like notebooks that have been closed and well preserved). However, in some of these cases, it seems likely that the original papers were in fact more acidic. Then we also have the examples of such inks fading in notebooks that are more than likely acid-free. 

 

This has made me wonder. Are acidic inks, such as washable blues, more likely to fade over time in acid free papers, or is the rate at which they fade more or less agnostic to the paper used? I could imagine that maybe such inks might have lasted longer in the short term on acidic paper (up to the point where the papers disintegrated) because the inks rely on acidity to retain their color. This could explain a little bit why some modern fade tests for some inks that are known to be more neutral or alkaline tend to fair better? 

 

I thought that I had read a comment somewhere here years ago suggesting this, but I can't find it now. 

 

Does anyone have a good answer to this one? 

 

Basically, are acidic inks like common Royal Blue inks more likely to fade in acid-free papers over time? Are some inks more prone to fading in acid-free papers because they are naturally more acidi or alkaline? I don't know, and I want to know!

[arcfide]

The previous discussion I am thinking about might have been this one: 

 

[InesF]

@arcfide, the most important thing is to have an idea about the time span.

I still have notebooks from 1967 where I wrote with washable blue ink and, although the lines appear to be a bit more pale than they were 50 years before, the text is still perfectly readable. I guess, the colour will disappear eventually, may it be in 100, 200 or 500 years? I don't know.

What I wrote in a diary from 2008 with a self mixed ink based on Waterman Blue and Pelikan 4001 Black (why I did this, escapes me now, because these two do not fit well together) had aged quite noticeably faster. The blue is almost completely gone after 15 years and only grey lines remain. However, also this text is still perfectly readable.

 

If you write with an alkaline ink (because the dye requires it) on an acid producing paper, you have a 50:50 chance that either nothing spectacular or something very bad happens over many, many, many years. I guess, before the ink fades the paper will become brown and brittle - that's the real disadvantage of acid producing paper. [Now drawing a scenario in my imagination: ink and paper neutralising each other over time, so the dye may become unstable but the paper is conserved ]

If you combine a heavily acidic ink (iron gall of old recipe, modern Royal Blue is not acidic enough) with an acid producing paper you will definitely see the well known disintegration effect - after 100 (or more) years.

[arcfide]

11 hours ago, InesF said:

I still have notebooks from 1967 where I wrote with washable blue ink and, although the lines appear to be a bit more pale than they were 50 years before, the text is still perfectly readable. I guess, the colour will disappear eventually, may it be in 100, 200 or 500 years? I don't know.

What I wrote in a diary from 2008 with a self mixed ink based on Waterman Blue and Pelikan 4001 Black (why I did this, escapes me now, because these two do not fit well together) had aged quite noticeably faster. The blue is almost completely gone after 15 years and only grey lines remain. However, also this text is still perfectly readable.

 

This is what makes me curious. There are comments from more than one person as far as I can tell that indicates otherwise fungible acidic inks like washable blue inks, appear to fade a little, but not substantially, in pre-1980's notebooks that are likely to have acidic or at least, less buffered papers, whereas there are lots of cases of increased fading in modern papers, most of which are likely to be acid-free or at least, less acidic. 

 

While the acidic paper will obviously age more poorly itself, there seems to be more than one instance of such acidic paper, for its lifespan, at least, preserving the color of washable blue inks better than the archival or acid free papers that we often use today. This makes me wonder about whether some inks today are just much more prone to fading in acid free papers than others, despite being generally okay in less buffered paper? 

[InesF]

On 11/23/2023 at 8:48 PM, arcfide said:

While the acidic paper will obviously age more poorly itself, there seems to be more than one instance of such acidic paper, for its lifespan, at least, preserving the color of washable blue inks better than the archival or acid free papers that we often use today. This makes me wonder about whether some inks today are just much more prone to fading in acid free papers than others, despite being generally okay in less buffered paper? 

Indeed, that's a highly interesting observation and theory. It has some logic in it.

Unfortunately, in this case I have no own empirical observations to contribute. I'm looking forward if some more evidences may be submitted to this thread.

[amper]

Unfortunately, without knowing the exact composition of the specific dyes, it's impossible to make any kind of determination as to the likelihood of any chemical interaction. Unlike with artists' media, where the composition is usually explicit and the color is composed of pure pigments, dye-based inks are rarely documented to the same extent, and in most cases, the formulae are regarded as trade secrets.

You'd need to speak to a dye chemist who is imtimately familiar with the fountain pen ink industry, specifically, to have a good idea.

[txomsy]

OK. So I went back to some old notes... I have a notebook I bound myself while in primary school but used much later. So the paper must be from the late 60's, early 70's (most likely around 1972-3). But It wasn't written until '83 (I can tell because the notes are on Microbiology which I took on '83).

 

NB, thanks, it turns out it is mostly unused and has some very FP friendly uncoated, rough paper.

 

Anyway, thing is, the pages have yellowed noticeably (but not much), yet the notes are perfectly readable. Royal Blue written with an EF is perfectly readable, maybe it has faded slightly, but I can't tell for sure. There are also notes in Blue-Black, which most likely was an IG ink at the time, and these haven't faded at all.

 

Something similar applies to my name written in the first page of the books. Fluorescent marker, however, is almost gone.

 

Indeed. I just checked some Biophysics notes (1980) in a number of different colors (black, blue black, blue, green...) and although the paper has yellowed in all cases, the ink looks as good as if just written.

 

This, I think, is irrespective of light exposition (although I haven't used that notebook much, I have used others a lot, but the same observations apply).

 

The next question is whether the same would happen in good paper. This is more difficult to test: as a student I would normally go for cheap supplies. But I do conserve old textbooks. While many have yellowed, some were in good paper (Medicine books, being very expensive would sometimes use good paper). It is difficult to find notes (I would normally gloss in pencil or remark with highlighter, but I did find a few.

 

In good paper, the fluorescent highlighter has preserved rather well, but so have fountain pen underscores and the few notes I could find. This is on textbooks from as far back as 1977. The notes from the 80's I feel less confident: by that time I already was looking for permanent inks. although at the time they were notably difficult to get by, so, most likely blue notes from the 80s were in Royal Blue, not permanent blue, but I can't be sure, however, the notes from the 70's I feel pretty confident that were in washable blue.

 

My conclusion is that, regarding FP ink, there doesn't seem to be much difference among papers. Yellowed paper seems to have very slightly -if ever- clearer blues than non-yellowing paper, blue blacks are as strongly marked in one paper as in the other, and yellow/green fluorescing marker has really almost completely faded (though still recognizable) on yellowed paper but not on better quality paper.

 

The only place I see noticeable fading is in some notes I took while preparing the Neurobiology exams in '83, which I took on cheap, coated, poll paper (I'd use the back side to write summaries) and preserved unbundled. In these, and only in the first pages, which have been exposed to light ever since (I kept them in a grid, box in the front part, exposed), I saw some fading (say to half intensity) of blue (and I repeat, only in the first few pages). These notes have yellowed a lot (actually "browned"), and yet, green (which certainly wasn't permanent), blue or blue-black are still as crisp as the first day.

 

By comparison, I have some "cheap edition" books from those times. It is interesting that the pages have darkened significantly, and even more interesting that the first two-three pages, facing an ex-libris sticker, show a noticeable lack of darkening in the area that was covered by the sticker. I find it curious because these books have been always in my library, packed among many other books, so while it looks like a shadow, the possibility that light might have creeped through meters of paper to leave that trace has me, I'd say, skeptic. This doesn't seem to happen with other books with the same sticker.

 

I mention it because I wonder if it might be possible that some of the fading reported were due not to light but to other effects, maybe chemical interactions with the paper itself.

 

[PJohnP]

I have found marginal notes on old pulp magazines and books from the 'forties and 'fifties.  I've also seen these on comic books of those eras, which were printed on some awfully cheap paper.

 

In most cases, where the magazines etc. were not placed in a high-light environment, the notes were still very readable, even if the paper of the pages was flaking and chipping at the edges from yellowing and acid-induced-age.

 

However, some items that were likely in high-light environments were becoming unreadable both with the notes and the printed materials.

 

I can't say that I used highlighters, especially not in textbooks that I might need to resell as a (somewhat) economical postgraduate,  so I have no anecdotal comments on those applications.

 

However, I did remark on old class notes in another thread, along the lines of, "All ink fading is local."

 

 

 

John P.

[arcfide]

This is some really interesting information! Thanks very much for sharing. 

 

I also found this:

 

Prof. Blumes Tipp des Monats (chemieunterricht.de)

 

Assuming that we restrict the question to that of Royal Blue inks, which can be erased with an Ink Eradicator, then we may have a pretty good idea of the type of dyes used, or at least the sort of reaction that they are susceptible to. At that point, I then wonder whether the additional calcium carbonate is able to induce something of a similar effect over time? I found this document on the use of paper sizing:

 

HubbeM_05_AcidicAlkSizing_AIC_BookPaperAnnual.pdf (ncsu.edu)

 

 

[TSherbs]

Interesting information. Thanks for sharing it all.

[txomsy]

After reading the 'all fading is local" thread, I just realized one point often overlooked:

 

Traditional (and many of todays') permanent ink was iron gall (IG) ink. IG inks are typically based on iron (what a surprise!) with added dye(s) to give it a color when writing. Typically the dye is not permanent, but the iron will bind to paper and remain.

 

What this means (and has been mentioned many times) is that the iron remains, the dye doesn't. Depending on the amount of iron that binds to the paper, the remaining color may range from a black to grey to brownish to sepia to clear brown. But that change in color is not due to fading, although it may look like the original ink has faded, but to the impermanence of the non-IG component (if any) and the quantity of iron bound; it is something that might frequently be expected as the extra non-permanent dye disappears according to its own properties (which need to be fading).

 

As an example, I have read digitized manuscripts from a thousand years ago where the writing on some pages would look pitch black and in others would look clear sepia or very "faded" (with no apparent relationship with the "popularity/interest" of the content --which might have led to higher exposure to light otherwise--): as ink was hand made and it wasn't paper, the obvious explanation is not fading, but different iron concentrations (or maybe parchment quality/treatment).

 

So, it probably was the iron content that defined the final color, not light exposure/fading. And maybe the sizing/treatment of the parchment surface (in the measure it affected the amount of iron that could fix to the underlying substrate).

 

That would apply to traditional permanent inks.

[PJohnP]

9 hours ago, txomsy said:

After reading the 'all fading is local" thread, I just realized one point often overlooked:

 

Traditional (and many of todays') permanent ink was iron gall (IG) ink. IG inks are typically based on iron (what a surprise!) with added dye(s) to give it a color when writing.

 

 

Another point not always considered in IG inks is where the gall comes from - tree galls typically from the oak family but not exclusively that family.  The galls would differ significantly by location, type of tree, climatic conditions the year the galls formed, etc.   In addition, the galls were then fermented changing the concentration of the solution (somewhat) with the efficiency of that process.  The ferrous sulfate used in IG ink would not be a pure compound, as the iron materials used to formulate it would not always be pure iron, nor would the sulfuric acid used in the reaction be pure.

 

Commercially derived chemicals going into ink formulations are not exactly analytical or pharmaceutical grade purity, leading to a fair set of threads here on FPN speculating on ink batches' colours and properties, but the permutations of materials in IG inks of even a century past would be orders of magnitude more complicated.  I suppose if we could run colour chromatography on every ink, perhaps mass spec testing, and some other thoroughly exhaustive analytical chemistry tests for components, develop a matrix of many dimensions, attempt to plot the different variables as much as possible, we might get some further ideas.  If the initial colours and properties would be so variable, predicting fading characteristics on any of thousands of paper types just might be difficult, too.

 

All ink fading is local.  <warm and radiant smile>

 

As a side comment, I do find the various ink fading tests here on FPN rather intriguing.  For "local conditions", we could look to Amberlea's tests of a decade back, as I've yet to see anyone else conduct tests through windows on a railroad caboose in a hot western state *.  Not only did she test ink on paper, but she tested ink in bottles, steins, and other vessels.  To the very best of my knowledge, no one else has duplicated her specific local conditions, nor the breadth of her tests.  A polite tip-of-the-hat is extended today to her efforts over the years.

 

 

 

John P.

 

 

* Enquiries about the circumstances leading to a caboose available for the testing should be forwarded to her and not me.  While I met her briefly at the LA Pen Show years back, I have no idea at all how or why she had a caboose available.  With respect to Amberlea, I can only say that she was a lovely person to talk with, and to my knowledge, she never drank ink at a TSA checkpoint following the show (an obscure reference for another person I met at the same show who later had photos shown here on FPN of her drinking ink from the bottle at a TSA checkpoint).

[Runnin_Ute]

The attached signature is now over 100 years old. The book it is in is as well. What ink was used is an unknown as grandpa died in 1959. I was a toddler then.  An iron gall? Perhaps, perhaps not. Grandma died in 1994, years before I started using fountain pens. 

[XYZZY]

On 11/27/2023 at 11:48 PM, txomsy said:

Traditional (and many of todays') permanent ink was iron gall (IG) ink. IG inks are typically based on iron (what a surprise!) with added dye(s) to give it a color when writing. Typically the dye is not permanent, but the iron will bind to paper and remain.

 

I'm not an IG expert, my experience limited to Diamine Registrars, R&K Salix & Scabiosa, and KWZ Gummiberry & Blue Black, and reading FPN...  I think Diamine Registrars has a very fugitive blue dye in it, perhaps even intentionally fugitive.  It's certainly not wimpy blue when it goes down, but as a sometimes user of that ink it certainly feels like the intended final color is black and not blue-black.  Diamine support never replied to my emails asking about this.

 

Whereas as IGs that claim to be modern formulations (not that anybody knows what that actually means), seem to be a legit nice dye-based ink, but with some IG thrown in to give it a bit of something-black appearance.

[amper]

According to what I've been reading recently, iron gall ink was first mentioned in the early 12th Cen BCE (1100's), by a monk named Theophilus, but it wasn't until 1748 that a scientific investigation into the proper ratios of components was made by British chemist William Lewis. Then in 1832, I believe, Henry Stephens hit upon the idea of adding a blue dye to it, creating the first modern "blue-black" iron gall ink, which subsequently came to be required by law in the UK for birth and death registries (thus, "Registrar's Ink"), and similar inks were adopted by many governments for official records. The Stephens company ceased production in 1985, apparently, but of course other brands are available, now.

[AceNinja]

1 hour ago, XYZZY said:

I think Diamine Registrars has a very fugitive blue dye in it, perhaps even intentionally fugitive.  It's certainly not wimpy blue when it goes down, but as a sometimes user of that ink it certainly feels like the intended final color is black and not blue-black.

yes that's my experience as well.  1-2 months after laid down on a page, the diamine registrar's will just looks like a black ink, with a very very very slight tinge of blue.  One would not normally notice the blue unless there's other black ink on the page for comparison.

[arcfide]

8 hours ago, XYZZY said:

 

I'm not an IG expert, my experience limited to Diamine Registrars, R&K Salix & Scabiosa, and KWZ Gummiberry & Blue Black, and reading FPN...  I think Diamine Registrars has a very fugitive blue dye in it, perhaps even intentionally fugitive.  It's certainly not wimpy blue when it goes down, but as a sometimes user of that ink it certainly feels like the intended final color is black and not blue-black.  Diamine support never replied to my emails asking about this.

 

Whereas as IGs that claim to be modern formulations (not that anybody knows what that actually means), seem to be a legit nice dye-based ink, but with some IG thrown in to give it a bit of something-black appearance.

 

The idea of the blue-black color is kind of a new thing derived from the effects of traditional iron gall inks. Traditionally, and this is still the case with traditional dip pen inks, a proper iron gall ink will go down some color, but it will turn black in color after "curing." All traditional iron gall inks were supposed to be black in color by the end, not something else. You can find, for instance, in some of the old ink manuals, a discussion of how to evaluate good inks, and these inks were all supposed to achieve a good solid black color after drying, and all of these inks were iron gall inks. 

 

If you lay down the ink as thickly as you normally would with a good dip pen, you'll find that many of these traditional iron gall inks do in fact behave this way. However, to make some inks more fountain pen friendly, the inks had to be made more fluid and the newer formulations didn't have quite the same IG make-up, as this would lead to excessive precipitation too easily. So, all traditional blue black inks were always supposed to go black over time. The blue was always meant to be an incidental thing to help the writing (since more traditional formulations were hard to see on the page before they turned black). 

 

The actual color blue black comes about after fountain pens have influenced the inks and caused ink makers to want to mimic the traditional hues that you would normally see in a dye-based ink. Originally, that term mean "blue to black" not "blue-ish black," but after the dye-based fountain pen inks, it becomes a color independent of the formulation with iron gall. 

 

Now, it's also worth noting that we have some super saturated, very black black inks. In the past, you wouldn't necessarily have expected to have such levels of super saturation. What we might think of as a grey iron gall line would have been considered black at the time, not "grey-ish". We're relatively spoiled in this respect. Now, there was a recognition by people at least in the early 1900's that India ink (or "lamp black" inks) were exceptionally dark, but that was in comparison to "standard black" inks, of dye and iron gall, which were obviously less so. This can explain why so many of the more traditional inks that we think of for fountain pens today are considered "light black" inks, or even "grey" by some people. That's of course not counting the fact that I get the distinct impression that many pens of the era wrote a little wetter than modern ones often do.