Biocide Shootout Tests

[SamCapote]

This is a new thread started after posting about a SITB fungal contamination in nearly every one of the 56 bottles of DeAtramentis inks I ordered from Art Brown's in New York, (and receiving another set of 56 replacement bottles from DeAtramentis - direct from Dr. Jansen) which also arrived with SITB. I tried to filter the contaminated inks and add 3 drops Tryphon's Sterilink which was 3 times as much as Giovani recommended to prevent fungus. I was very meticulous. This procedure was quite time consuming, so I only did about 40% of the bottles at the first session back in May/June 2010. I stored the filtered, biocide-treated bottles in plastic drawers, mostly shielded from the light, and were kept at room temp (65 to 75 F). I was planning on resuming filtering and treating in early August, but was shocked to see that my initial 3 drops of Tryphon Sterilink treated bottles were right back to the same slimy SITB & visible strands (easy to verify in lighter colored inks) as when I started all this in May!

 

I have delayed started this thread and next step, because I sent one of the Yellow-Orange treated bottles to Giovani (Tryphon owner) after speaking with him at length. He claimed this is the first case where his Steril-Ink biocide did not kill and/or prevent fungal growth--and especially since I put 3 drops in a 35 ml bottle where normally he only recommends using a single drop. I have made at least 5 phone calls, and 6-7 emails trying to find out what he thought upon seeing the contamination, as I wanted to do this thread in partnership with him, since I know so many believe in his Steril-Ink for this very purpose. I have found that he is traveling back and forth to Europe, and as of today, his wife Syliva, knows he has not yet looked at my Yellow Orange bottle he received in early August, and continues to be busy with travel.

 

So, I have now lost confidence in DeAtramentis (& Dr. Jansen) Inks, Art Browns store, Giovani, & his Tryphon Steril-Ink. I am going to proceed on my own, using what I believe to be a reliable, scientific method. I spent a lot of time talking to Giovani, various chemical engineers, an ink manufacturer, reading, and searching for industry biocides, and knowing that Phenol was successfully used in inks before everyone started freaking out about its cancer risks in high doses. I wanted an alternative to Tryphon's Steril-Ink, and settled mainly on Sporicidin Disinfectant Solution because it has Phenol, and the head of development for the product spoke with me at length (Steven Leung, Director of Development, Contec, Inc., Sporicidin Division), and believed it would work very well for my intended purpose, and wanted me to keep him posted on results. In the process of my research, I was also able to have a well known ink manufacturer send me a sample of his proprietary biocide used in their inks (don't ask me for details, as I gave my word to maintain privacy).

 

You can look at post #50 in the original thread to see more about my conversations with Sporicidin, and plan for testing here, which I have modified slightly.

 

Here are two thumbnail photos of the current state of the DeAtramentis (wedge-shaped) bottle that was filtered and treated in late May.

 

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-01s.jpg

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-02s.jpg

I had about 32 ml of ink, so I pipetted about 3 ml into the first of ten small plastic vials I got from Dillon here. This is "Control #1." Next I used the same filter and funnel system as in my original thread to clean the bulk of the fungal growth from the ink. I took about 3 ml and put it in vial #2 as a "Filtered Control." Then I transferred about 3 ml of the filtered ink to each of #2 through #10 vials. Next, I added the three biocides as shown below.

 

1) Original contaminated ink, unfiltered & untreated (control)

2) Filtered but untreated ink (2nd control)

 

3) Filtered,

1 drop Tryphon Sterilink ("TS)

4) Filtered,

2 drops Tryphon Sterilink

5) Filtered,

3 drops Tryphon Sterilink

6) Filtered, 1 drop of Sporicidin Disinfectant Solution ("SPOR")

7) Filtered, 2 drops of Sporicidin Disinfectant Solution

8)

Filtered, 3 drops of Sporicidin Disinfectant Solution

9) Filtered, 1 drop Inkmaker's Propietary Biocide ("IPB")

10) Filtered, 2 drops

Inkmaker's Propietary Biocide ("IPB")

The interesting thing I almost always saw happen when adding Trypon's Steril-Ink was an apparent color interaction with most inks, at least on the surface which is shown in images below, but mixing/inverting resolves it without a persisting color change or precipitate. All three biocides are clear, as shown in final sets of images below where I transferred some into the vials. Steril-Ink smells like a detergent--Ivory soap type smell. Sporicidin smells like Phenol, but not overwhelming (for those who didn't read my post #50, Phenol is still contained in Chloraseptic throat spray which should be enough evidence on its safety. The Inkmaker's Propietary Biocide has a pungent, acrid, chemical smell, but not of an acidic type aroma. All three biocides mixed well, with no evidence of problem. The drop size was from the disposable 5ml plastic pipettes. With the small 3 ml vials, my using 1, 2, 3 drops would compare to adding 10, 20, 30 drops into a 30 ml ink bottle, or twice that for a 60 ml bottle.

 

Now the vials sit on a bookshelf, not in direct sunlight, but not put away in a drawer. I will look at them every 1-2 weeks, and report the results. I have the highest hopes for the Sporicidin because of its phenol. Perhaps even the Steril-Ink will work at doses 10/20/30 times as much as Giovani said was needed.

 

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-03s.jpg

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-04s.jpg

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-05s.jpg

 

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-06s.jpg http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-07s.jpg http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-08s.jpg http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-09s.jpg

[geoduc]

Thanks for doing this, it will be very interesting to see the results.

[Paddler]

I tried both Sterilink and Ink Safe in homemade black walnut ink at up to three times the recommended dose. None of the trials prevented mold or bacterial growth. Of course, walnut ink is a complex mixture of organic compounds and makes an excellent growth medium for molds and microbes. Some of the components may have neutralized the biocides.

 

Paddler

[SamCapote]

I'm also adding Sporicidin to a bevy of other inks just to see if anything happens to their color/performance over time in response to this potential biocide. So far none have exploded, but I have not done BSB yet.

[Sandy1]

Did someone say '

Shoot-Out'?

[SamCapote]

Did someone say '

Shoot-Out'?

 

LOL! That's one way to put an end to a pesky fungus.

[Twyla]

Thanks for putting so much time and effort into this, I know that some of us are quite looking forward to seeing your results.

[pharmacist]

There are two very effective fungicidical/fungistatical products and excellent for ink making: salicylic acid and phenol. The concentration must be high enough: for salicylic acid this is 1 gram/500 ml and for phenol 1 gram/1000 ml. So you must calculate the total amount in your solution. Both preservatives are enhanced by lowering the pH-value (acidifying the ink by adding hydrochloric acid).

[SamCapote]

There are two very effective fungicidical/fungistatical products and excellent for ink making: salicylic acid and phenol. The concentration must be high enough: for salicylic acid this is 1 gram/500 ml and for phenol 1 gram/1000 ml. So you must calculate the total amount in your solution. Both preservatives are enhanced by lowering the pH-value (acidifying the ink by adding hydrochloric acid).

 

Thanks very much for your help, as I am trying to figure this out for the whole community. I can call back Steven Leung who is the Director of Development, Contec, Inc., Sporicidin Division for confirmation but thought I would get your input first.

 

If I look at the MSDS of Sporicidin, it lists the Phenol as 1.56% by weight. Remembering back on the distinctions of molarity and molality, I don't actually know what their starting g/L concentration is before adding that to get the 1.56%, or if that is considered pure in which case Sproicidin should be 1.56 gram per Liter ? I have a feeling it is not necessarily that straightforward. These are 22oz (650ml) bottles. I also like the safety factors I read in this PDF, in terms of it's use with fountain pens.

 

I know the two bottles of pharmaceutical grade "Liquified Phenol USP" shown in this photo only list as 4oz, and are in some kind of oil type vehicle, as they don't complete mix in water. It may just be that I was just seeing the reported 6.75% soluability in water. Obviously, that is much more concentrated, but I'm not sure how to translate it back to your g/L suggestion. Because it also requires a prescription, I was trying to find something that is regarded as safe, readily available, and effective. I can't think of anything better than Sporicidin. Look at the tremendous spectrum of biocidal activity with what I am testing.

 

My concern with lowering the pH with HCL is that would not be practical/safe for the average user, who will not have an accurate way to monitor the changing pH, and it may very well damage/precipitate out certain ink formulations if the ink pH was changed dramatically. See my pH testing thread results here with note of some of the very high pH inks.

[atypical]

This looks like a very interesting experiment.

 

I checked some old (1939) DIY ink recipes and found the following phenol concentrations:

- Document ink (iron-gall) - phenol: 1 gram , water: 1 litre

- Red ink (eosin dye) - phenol: 15 grams, water: 3500 grams

- Blue ink (naphthol blue-black dye) - phenol: 7 grams, water: 3500 grams

- Bright blue ink (methylene blue dye) - phenol: 15 grams, water: 2.5 litres

- Black ink (nigrosin dye): phenol: 15 grams, water: 2.5 litres

 

From the 1994 MSDS for Koh-I-Noor India Ink: 0.45 % phenol.

 

A modern recipe for iron-gall ink from Kremer Pigmente specifies 1 gram of ascorbic acid in 1 litre of water to prevent moulding.

 

I hope this information is of some use to you.

[Sandy1]

Did someone say '

Shoot-Out'?

 

LOL! That's one way to put an end to a pesky fungus.

 

Well, at times such as this, when faced with problem/s like that, whachagonnado?

[Surnia]

There are two very effective fungicidical/fungistatical products and excellent for ink making: salicylic acid and phenol. The concentration must be high enough: for salicylic acid this is 1 gram/500 ml and for phenol 1 gram/1000 ml. So you must calculate the total amount in your solution. Both preservatives are enhanced by lowering the pH-value (acidifying the ink by adding hydrochloric acid).

 

Thanks very much for your help, as I am trying to figure this out for the whole community. I can call back Steven Leung who is the Director of Development, Contec, Inc., Sporicidin Division for confirmation but thought I would get your input first.

 

If I look at the MSDS of Sporicidin, it lists the Phenol as 1.56% by weight. Remembering back on the distinctions of molarity and molality, I don't actually know what their starting g/L concentration is before adding that to get the 1.56%, or if that is considered pure in which case Sproicidin should be 1.56 gram per Liter ? I have a feeling it is not necessarily that straightforward. These are 22oz (650ml) bottles. I also like the safety factors I read in this PDF, in terms of it's use with fountain pens.

 

 

1.56% by mass, so if your solution were 500g, then 1.56% of that total mass is phenol (also at a specific temperature). mL count here won't help much as you can't calculate from density (you don't know how the compounds interact, and how that would affect their total volume), unless you measure out a specific volume accurately and weigh it (at a specific temperature, probably 25ºC)

[pharmacist]

@atypical:

 

As specified: the more acid inks (iron gall) need less phenol for preservation, but the formula of Kremer using only ascorbic acid: this is NOT a good idea. It helps a bit, but ascorbic acid is instabile and will deteriorate overtime. Therefore salicylic acid is much more effective and it's very stabile. Eosine is an alkaline and therefore the amount of phenol should be increased to counter the diminishing effect of the alkaline environment.

 

About Sporicidin: so when you calculate back to the necessary amount of phenol (0.1 % of the total ink amount) you should add 1 ml per 15-16 ml of ink to get the right concentration, so a few drops is NOT enough !!! The difference in density is negligible, so calculation on this to compensate for the density can be safely omitted.

[SamCapote]

This looks like a very interesting experiment.

 

I checked some old (1939) DIY ink recipes and found the following phenol concentrations:

- Document ink (iron-gall) - phenol: 1 gram , water: 1 litre

- Red ink (eosin dye) - phenol: 15 grams, water: 3500 grams

- Blue ink (naphthol blue-black dye) - phenol: 7 grams, water: 3500 grams

- Bright blue ink (methylene blue dye) - phenol: 15 grams, water: 2.5 litres

- Black ink (nigrosin dye): phenol: 15 grams, water: 2.5 litres

 

From the 1994 MSDS for Koh-I-Noor India Ink: 0.45 % phenol.

 

A modern recipe for iron-gall ink from Kremer Pigmente specifies 1 gram of ascorbic acid in 1 litre of water to prevent moulding.

 

I hope this information is of some use to you.

 

Interesting information. Back when phenol was used commonly, they may have used it in much higher concentrations. I'm hoping the weaker concentrations (as in my test model) will still be effective. The hard thing is finding something like Sporicidin Disinfectant Spray which passes all the safety measures, and is highly effective against all microorganisms. (Note: I am not talking about the "Sterilizing & Disinfecting" version of their product which has a separate bottle that must be added to activate it, and contains glutaraldehyde which doesn't last long and would be harmful to pens.). Using full strength phenol crystals or USP grade liquid phenol would not be safe or practical--even if I could personally achieve those amounts.

 

So this pursuit needs to have a practical/available side to it, given that I don't believe Tryphon's Steril-Ink is working. I don't know of anything else that is safe with pen parts, gives a long term protective benefit, and won't ruin the various ink formulations. Obviously the various ink types and wide ranges of pH may cause problems. I do have a couple other ink bottles (one is a Private Reserve) with unrelated fungus contamination, so I'll use that for another study if it looks like this yellow-orange growth is working.

[SamCapote]

@atypical:

 

As specified: the more acid inks (iron gall) need less phenol for preservation, but the formula of Kremer using only ascorbic acid: this is NOT a good idea. It helps a bit, but ascorbic acid is instabile and will deteriorate overtime. Therefore salicylic acid is much more effective and it's very stabile. Eosine is an alkaline and therefore the amount of phenol should be increased to counter the diminishing effect of the alkaline environment.

 

About Sporicidin: so when you calculate back to the necessary amount of phenol (0.1 % of the total ink amount) you should add 1 ml per 15-16 ml of ink to get the right concentration, so a few drops is NOT enough !!! The difference in density is negligible, so calculation on this to compensate for the density can be safely omitted.

 

You may be right, but the thing I don't know is if there is a lower practical biocide threshold with phenol, or the overall formulation of Sporicidin. In part I'm extrapolating in terms of using only drops from the killing effect of the Sporicidin spray as promoted in their literature, the recommendation of their Director of Development, amounts recommended by Giovani (with his Steril-Ink), and conversations with the Inkmaker's propietary biocide.

 

Pharmacist, do you have a source for the 1 gram/Liter being the effective threshold? The good news is that these 22 oz spray disinfectant bottles has 650ml, so it's not a big problem to put 1-2 ml in a 30 ml bottle of ink in terms of cost effectiveness. They also come in gallon sizes (128 oz = 7,800 ml), which is only $32 so if I need to add that much to all my bottles, it would still be relatively inexpensive. I think based upon your advice, I am going to add 0.2 ml of Sporicidin to 3ml vial #6 in first post, instead of 1 drop.

 

I just thought of another simple test I added, since I grind my own hard red winter wheat to make my own bread. I mixed up a 1/4 tsp of SAF Instant Yeast with a 1/8 tsp of sugar in about 50 ml of warm water. After 30 mins, I could verify that yeast was growing and giving off that lovely bread yeast aroma. I transferred 5 ml into some more plastic vials (with one being the control), and added various drops of Sporicidin to the vials and capped them. 3 drops did not stop the growth and bubble formation, so I carefully opened it and added 0.2ml of Sporicidin to bread yeast vial. It now smells like phenol instead of yeast aroma.

Edited October 20, 2010 by SamCapote

[pharmacist]

@atypical:

 

As specified: the more acid inks (iron gall) need less phenol for preservation, but the formula of Kremer using only ascorbic acid: this is NOT a good idea. It helps a bit, but ascorbic acid is instabile and will deteriorate overtime. Therefore salicylic acid is much more effective and it's very stabile. Eosine is an alkaline and therefore the amount of phenol should be increased to counter the diminishing effect of the alkaline environment.

 

About Sporicidin: so when you calculate back to the necessary amount of phenol (0.1 % of the total ink amount) you should add 1 ml per 15-16 ml of ink to get the right concentration, so a few drops is NOT enough !!! The difference in density is negligible, so calculation on this to compensate for the density can be safely omitted.

 

You may be right, but the thing I don't know is if there is a lower practical biocide threshold with phenol, or the overall formulation of Sporicidin. In part I'm extrapolating in terms of using only drops from the killing effect of the Sporicidin spray as promoted in their literature, the recommendation of their Director of Development, amounts recommended by Giovani (with his Steril-Ink), and conversations with the Inkmaker's propietary biocide.

 

Pharmacist, do you have a source for the 1 gram/Liter being the effective threshold? The good news is that these 22 oz spray disinfectant bottles has 650ml, so it's not a big problem to put 1-2 ml in a 30 ml bottle of ink in terms of cost effectiveness. They also come in gallon sizes (128 oz = 7,800 ml), which is only $32 so if I need to add that much to all my bottles, it would still be relatively inexpensive. I think based upon your advice, I am going to add 0.2 ml of Sporicidin to 3ml vial #6 in first post, instead of 1 drop.

 

I just thought of another simple test I added, since I grind my own hard red winter wheat to make my own bread. I mixed up a 1/4 tsp of SAF Instant Yeast with a 1/8 tsp of sugar in about 50 ml of warm water. After 30 mins, I could verify that yeast was growing and giving off that lovely bread yeast aroma. I transferred 5 ml into some more plastic vials (with one being the control), and added various drops of Sporicidin to the vials and capped them. 3 drops did not stop the growth and bubble formation, so I carefully opened it and added 0.2ml of Sporicidin to bread yeast vial. It now smells like phenol instead of yeast aroma.

 

About the usage of preservates. There are some agents like quartenary ammonium salts which acts both as preservative and also as lubricant to make the ink flow better, but some dyes complexes these quartenary compounds neutralising its preservative action. Phenol is for example considerably less effective in alkaline solutions, hence the increased amount when using in red dye inks (which tends to be often alkaline).

 

For most ink makers phenol and the safer salicylic acid are effective and cheap preservatives, taking care in which type of ink you are putting these in. Acidic inks need less, alkaline inks need more of it. Ascorbic acid (vitamin C) is NOT a good preservative, since it is rapidly degraded over time.

[SamCapote]

@atypical:

 

As specified: the more acid inks (iron gall) need less phenol for preservation, but the formula of Kremer using only ascorbic acid: this is NOT a good idea. It helps a bit, but ascorbic acid is instabile and will deteriorate overtime. Therefore salicylic acid is much more effective and it's very stabile. Eosine is an alkaline and therefore the amount of phenol should be increased to counter the diminishing effect of the alkaline environment.

 

About Sporicidin: so when you calculate back to the necessary amount of phenol (0.1 % of the total ink amount) you should add 1 ml per 15-16 ml of ink to get the right concentration, so a few drops is NOT enough !!! The difference in density is negligible, so calculation on this to compensate for the density can be safely omitted.

 

You may be right, but the thing I don't know is if there is a lower practical biocide threshold with phenol, or the overall formulation of Sporicidin. In part I'm extrapolating in terms of using only drops from the killing effect of the Sporicidin spray as promoted in their literature, the recommendation of their Director of Development, amounts recommended by Giovani (with his Steril-Ink), and conversations with the Inkmaker's propietary biocide.

 

Pharmacist, do you have a source for the 1 gram/Liter being the effective threshold? The good news is that these 22 oz spray disinfectant bottles has 650ml, so it's not a big problem to put 1-2 ml in a 30 ml bottle of ink in terms of cost effectiveness. They also come in gallon sizes (128 oz = 7,800 ml), which is only $32 so if I need to add that much to all my bottles, it would still be relatively inexpensive. I think based upon your advice, I am going to add 0.2 ml of Sporicidin to 3ml vial #6 in first post, instead of 1 drop.

 

I just thought of another simple test I added, since I grind my own hard red winter wheat to make my own bread. I mixed up a 1/4 tsp of SAF Instant Yeast with a 1/8 tsp of sugar in about 50 ml of warm water. After 30 mins, I could verify that yeast was growing and giving off that lovely bread yeast aroma. I transferred 5 ml into some more plastic vials (with one being the control), and added various drops of Sporicidin to the vials and capped them. 3 drops did not stop the growth and bubble formation, so I carefully opened it and added 0.2ml of Sporicidin to bread yeast vial. It now smells like phenol instead of yeast aroma.

 

About the usage of preservates. There are some agents like quartenary ammonium salts which acts both as preservative and also as lubricant to make the ink flow better, but some dyes complexes these quartenary compounds neutralising its preservative action. Phenol is for example considerably less effective in alkaline solutions, hence the increased amount when using in red dye inks (which tends to be often alkaline).

 

For most ink makers phenol and the safer salicylic acid are effective and cheap preservatives, taking care in which type of ink you are putting these in. Acidic inks need less, alkaline inks need more of it. Ascorbic acid (vitamin C) is NOT a good preservative, since it is rapidly degraded over time.

 

It does appear with my little bread yeast experiment that the 0.25 ml in 4 ml vial wiped it out, where 3 drops did not. This was a pretty strong active yeast growth, that gives off little bubbles (? CO2) that makes it easy to verify the culture is alive. These are the results after 15 hours.

 

http://i61.photobucket.com/albums/h75/pike444/Biocides/Biocide-10s.jpg

 

These 5ml disposable pipettes have marks at 0.25, 0.5, & 1.0 ml. I confirmed that 25 drops are in 1 ml, 13 in 0.5, and 6 drops in 0.25ml.

 

http://i61.photobucket.com/albums/h75/pike444/Biocides/P200-10SCI.jpg

So the dose you are suggesting is making sense with this likely pH neutral household tapwater used for the bread yeast. Given that some of the inks are quite alkaline, I think there will need to be that adjustment upwards as you said. I would kind of hope to find a single dose for all ink types, depending on bottle volume, rather than having to remember a range of doses for various color and pH ranges of inks.

 

I am going to do one more bread yeast test where I find the exact number of drops to kill the yeast, just to double check. Again, this is pretty heavy, fast growing, and an agressive type of yeast, so I would hope that if my tests kill it, they would cover a lower grade, less active infection in our inks.

 

Then the next set of tests are to take 2 ml ink from every brand I have (I think I have 28 brands), and several colors within a brand (& check a few more pH measurements) to check for pH diversity with colors as you suggested. Then I will add 0.25 ml of Sporicidin to look for product incompatibility, dilution effect, or deteriorating effect on dye/pigment. I will make a swab mark in a book before adding the biocide, and then periodically afterwards to see how it changes.

 

This is great! Now we are using some real science to figure this out. It never really made sense to me that only one drop of Tryphon's Steril-Ink would be adequate to treat an entire 35-50 ml bottle--especially if it was already infected. Especially since his drops smell like a weak soap. Smelling the Phenol in the Sporicidin, and the pungent/acrid aroma of the Private Inkmaker's Proprietary biocide at least conveys some potency.

Edited October 20, 2010 by SamCapote

[SamCapote]

I have had some more good information from members in this thread and by PM's, (thanks especially pharacist!). I have also had several calls with Dow Chemical who have a large line of commerical biocides. Their best recommendation was Dowicil-75 which even has a listing here for use in Fountain Pen Inks at a concentration of 0.2 to 0.27% by weight. While I can obtain this, and will personally be using it, there are a couple of downsides that are in my way of being able to recommend it to the general community over the earlier mentioned Sporicidin Disinfectant Solution which is safe, affordable, and obtainable by anyone (at least in the USA).

 

The problems with the Dow Chemical Dowicil-75 is that it only comes in a powder, and requires a company/research applicable use status (they won't ship to a individual home end user). It must be mixed with respiratory protection to avoid inhaling the powder in an appropriate concentration by weight to give the recommended 0.27% dose, and that mixture used within 2 weeks. The treated ink remains protected for 2 years which is not a long time for large ink collections archival protection. And the clincher is that in only comes in large (expensive) drum containers. I just don't see that as being practical for most people.

 

Now the downsides to Sporicidin according to member "pharmacist" is that the 1.56% phenol will only be an effective biocide in inks below pH 8.0. The only inks I have found so far above that level are the Japanese inks (Pilot Iroshizuku & Sailor), so those may need to be considered untreatable unless you are willing to get into the Dowicil-75. I also do not know if European laws would allow shipment of Sporicidin since they are beserk about anything with phenol, even though this formulation is safe enough to be used in Chloraseptic throat spray, available at any grocery or pharmacy store in America. The other potential downside which I will be verifying is whether the dose of 1 ml of Sporicidin in 16 ml of ink (6% dilution) is enough to alter an inks appearance, and/or if it has any direct interaction effect on the dye/pigment--which I am testing for.

 

I'm in the process this weekend of doing a bunch more ink pH tests to see where more of them come out, akin to Greg Clark's old book, and will update this thread soon.

[SamCapote]

Well, as is often the case in life, I have good news & bad news. After only 3 weeks, my dear, lost, fungal friends have returned.

 

Surprisingly, every bottle now has clearly visible solid string-like growth....EXCEPT vials #9 & 10 which is the 1 & 2 drops of the "Proprietary Ink Maker's" biocide, which is still clear.

 

I have one other option in the works of getting a stronger concentration of the Sporicidin, but the doses I used were not BIO-CIDAL or BIO-STATIC at preventing the spores from hatching. You have to admire nature's tenacity.

 

But I'm not done yet. This just makes things more interesting.

 

This also validates what pharmacist said earlier about the amount of Phenol required.

[pharmacist]

Keep in mind the old iron gall ink contain both phenol in 0.1 % concentration AND the very low acidity due to the presence of hydrochloric acid. This is called a synergestic action: the combined action is much more potent than the individual phenol and hydrochloric acid alone. There are some more powerfull preservatives derived from phenol like eugenol (the main substance in clove oil), but eugenol has a low water solubility. Did you try benzalkoniumchloride (often found in waterbed conditioners) ? This too is a very powerfull preservative, but it tends to lower the surface tension of your ink. It should be combined with sodium edetate to synergestically enhance its action.