Ink Chemical Analysis

[jhylkema]

I know there are a lot of really, really smart people here, but do we have any analytical chemist types? If so, has anyone ever done any actual hardcore analysis (e.g., GC/MS) on any inks out there? If so, what were the results?

[Angeldust]

I considered doing this but then realised that no one else in the lab would appreciate me using QTOF time to analyse inks, screwing up our analytical columns with potential fluorophores (we make a lot of fluorescent molecules) and potentially contaminating HPLC needles with the same.

 

I also am not sure whether we'd actually learn much from having accurate masses on the dyes in ink, as far as I know the structures aren't published so there's no reference database.

 

Inks are also aqueous (and the dyes are likely sulphonates to facilitate solubility) necessitating reversed phase separation, so to potentially pull out all the different fluorophores you'd need a bulk of reversed phase silica and also a lot of ink to get enough of the individual components to, say, NMR. Not to mention the time requirements to complete all the necessary 2D NMR experiments for complete structural assignment.

 

Essentially, while possible, it wouldn't be cheap or quick and would likely tick off other scientists that rely on the instruments on a daily basis

[El Gordo]

I agree with Angeldust, analysis should be done for a reason. "Fun" could be one, but this is mostly not considered a sufficient reason in labs carrying expensive equipment dedicated to other jobs. There are so many inks with different colours, each carries different dyes/chemicals, the results would be quite different. So, first: what is the reason ?

 

This definitely does not mean that it has not happened, and a good idea would be to include forensics in search terms for ink composition (assuming you would like to know what is in a specific ink). You will end up with a lot of abstracts mentioning various techniques. Ink components can be separated for example by thin layer chromatography (sort of more scientific version of the kitchen towel colour separation trick) and analyse the separated components by spectrometry in the UV-VIS and IR range, capillary electrophoresis and NMR can be used as well. But as mentioned, depends what you want to know, how much you want to know, why and whether you would be willing to pay the bill for a specific ink.

[white_lotus]

Probably the wrong way to approach the problem.

 

While every individual commercial ink recipe is proprietary, for those in the industry the sources of dyes, surfactants, biocides, etc. are well known and readily available. And what is available to industry is often very difficult for the home user to obtain for either safety concerns or simply due to the volumes the chemical industry typically sells.

[jhylkema]

Interesting. I was thinking that all you would need to do is put a few drops of ink in the magic box, press the button, get a print out, and be able to whip up a batch of your favourite ink, all inside of 30 minutes less commercial breaks. After all, thats what they do on CSI every week!

[inkstainedruth]

Interesting. I was thinking that all you would need to do is put a few drops of ink in the magic box, press the button, get a print out, and be able to whip up a batch of your favourite ink, all inside of 30 minutes less commercial breaks. After all, thats what they do on CSI every week!

 

Yeah, but on CSI they could also get fingerprints off of surfaces that in the real world are actually not so amenable (wood grain, dusty surfaces).

Unfortunately I know this from experience, from when our old house was burglarized a number of years ago: the cops got a partial print off the back window (the point of entry) -- and that was it. The burglars made off with the TV, VCR, and part of the stereo (ironically the non-working component) and my husband's VCR tape of the Hunt for Red October (as well as the one IN the VCR -- a live recording of the women's figure skating finals in that year's Winter Olympics. Plus, a duffel bag and it looked as if the perp(s) rifled through some upstairs drawers, probably looking for cash.

Ruth Morrisson aka inkstainedruth

 

edited for formatting

Edited April 4, 2018 by inkstainedruth

[Lloyd]

A few years ago, SamCapote ran many inks through a very accurate pH analyzer and listed the results...which, in many cases, were quite surprising.

[Corona688]

Many dyes change color with PH. I saw but can't now find an MSDS for some old Sheaffer inks which had some eyebrow-raising PHes, the pink was something shocking like 2 or 3.

[wasteland]

A cursory Google search will show that there is scientific literature on the subject. Unfortunately, the full text typically requires a subscription to access but should be readily available to professionals.

 

Examples:

 

The analysis of fountain pen inks by capillary electrophoresis with ultraviolet/visible absorbance and laser-induced fluorescence detection

 

Chemical Composition of a Fountain Pen Ink

[Corona688]

I also am not sure whether we'd actually learn much from having accurate masses on the dyes in ink, as far as I know the structures aren't published so there's no reference database.basis

Their dyes can't be too proprietary or else they couldn't claim they were safe. In an extremely rare instance of the manufacturer accidentally releasing a dye name, blue varsities apparently use "direct blue 87", a soluble phthalocyanine.

 

I suspect the vast majority of dyes in fountain pens are found in this expensive book.

Edited April 5, 2018 by Corona688

[Corona688]

I agree with Angeldust, analysis should be done for a reason. "Fun" could be one, but this is mostly not considered a sufficient reason in labs carrying expensive equipment dedicated to other jobs. There are so many inks with different colours, each carries different dyes/chemicals, the results would be quite different. So, first: what is the reason ?

How does sheer cheapness sound? We're paying $20 and up for 50ml of 99% water, 0.7% surfactant, and 0.3% pigment. For the cost of the materials and a few minutes of work a lifetime supply of ink could be made.

[El Gordo]

How does sheer cheapness sound? We're paying $20 and up for 50ml of 99% water, 0.7% surfactant, and 0.3% pigment. For the cost of the materials and a few minutes of work a lifetime supply of ink could be made.

 

Their dyes can't be too proprietary or else they couldn't claim they were safe. In an extremely rare instance of the manufacturer accidentally releasing a dye name, blue varsities apparently use "direct blue 87", a soluble phthalocyanine.

 

I suspect the vast majority of dyes in fountain pens are found in this expensive book.

 

That's the point: if you know what dye you want to use, ok you can make (depending on where you live and your access to small volumes of chemicals (big is cheaper, but assuming you only want a stock for your own lifetime ...) about 8 l of ink based on direct blue 87, for some 80 - 90 dollar, dye cost only. Prepare to be stuck with one color for the rest of your life as well.

If you do not know what dye it is, and you want to analyse it per OP's suggestion: no single technique will give you all details on qualitative and quantitative composition. Looking at commercial labs with published pricelists on the internet for techniques mentioned in this thread, I guess it easily adds up to more than 1000 USD for a decent analysis (one ink). Don't know how far you would already get with 50 bottles of 20 USD, but you could definitely change colours somewhere along the road in this way.

Edited April 8, 2018 by El Gordo

[Corona688]

Heh, that's almost my situation already. Fortunately I really do love Prussian Blue.

 

There's a certain satisfaction in using something you've made yourself, I find, especially when it costs 35 times less than it would cost to buy it. You could fill a watercooler, give 95% away at your next pen meet (bring your own bottles, people!) and still have saved money.

 

You make a good point about the analysis costing $1000. Maybe we shouldn't try to duplicate commercial inks anyway. We could approach it from the other direction.

[Weaveras]

Having read Richard Binder's post on ink ratings based on his repair experience, I was kind of hoping to find something a little more scientific - for example, do Japanese inks really have issues with rubber sack based fillers? Does PH really have an impact on longevity? And more practically, why does my Rohrer & Klingner Salix run more dry than either my Lamy or Pilot inks? Do inks act as a lubricant while writing?

[welch]

In 1932, Parker applied for a patent on Quink. Here is the patent application, explaining each ingredient. It includes Solv-X, as best I can tell. According to FPN member Corniche, who found the patent (1,932, 248) Solv-X was "I believe Solv-X was a combination of Phenol, (fungicide) and amyl-xanthale, a flow enhancer. The latter chemical is referred to in the followings ways; 'flow promoter' and 'the trend of flotation.' I think Phenol was the 'solvent,' (Solv) and the amyl-xanthale provided the "X." Hence, Solv-X."

US Patent Office digitization:

http://pdfpiw.uspto.gov/.piw?PageNum...3DPN%2F1932248

[Tweel]

I found that patent myself some time ago. I think the term "xanthale" in the patent is a typo, and should be "xanthate" (a salt of xanthic acid). Sodium and potassium amyl xanthates are flotation agents for ore separation in the mining industry.

Edited May 26, 2018 by Tweel