Formalin to prevent fungus

cr frank · Jun 28, 2011

At the suggestion of forum members I am trying Formalin to prevent fungus forming on negs. I have in hand a bottle of Formalin MS. I am looking for help with proper use of this product. Such as correct dilution and duration of treatment. Any suggestions are appreciated.
thanks,
charles

BrianShaw · Jun 28, 2011

I can't help with that particular question since I've only used formalin as a gelatin hardener, but please make sure you use all safety precautions like good ventilation or a fume hood. That stuff is nasty bad.

Diapositivo · Jun 28, 2011

My E-6 stabilizer contains formalin at 4,75% and is diluted 1 + 49 so the final concentration is 0,095 % (1:1000). Dilution should better be made in demineralized water. This is the very last bath the film sees, so if you need adding something else (hardener, maybe antistatic, whatever) do it in the same bath.

Photo Engineer · Jun 28, 2011

You do not need formalin for B&W prints or negatives, as the silver metal itself is an antifungicide and bacteriostat. It is only used in color processes due to all of the yummy organics present and no residual silver if the process is done right.

For color, use about 3 - 10 ml of 37% formalin / liter of water. This is what I use and what we used to use in color processes.

PE

Роберт · Jun 28, 2011

27ml of 37% Formaldehyde in 1 ltr. destilled water is exactly 1% Formaline. I thought that normally 0,5% -1% is used for this. But due to the answer of PE it seems to be it can be even less.

cr frank · Jun 28, 2011

Photo Engineer said:
You do not need formalin for B&W prints or negatives, as the silver metal itself is an antifungicide and bacteriostat. It is only used in color processes due to all of the yummy organics present and no residual silver if the process is done right.

For color, use about 3 - 10 ml of 37% formalin / liter of water. This is what I use and what we used to use in color processes.

PE

PE,
Thanks for your response. This suggestion to use Formalin was offered in reference to a recent thread "a darkroom conundrum". In this thread are attachments which show what i am dealing with. Could you take a look at these and offer a opinion? Maybe this is not fungus after all.....?
charles

Photo Engineer · Jun 28, 2011

Do you have a URL Frank?

PE

georgegrosu · Jun 28, 2011

It is true that silver is a good antibacterial, but gelatin of film is a very good food and more for fungus.
In Actes du Symposium Technique Mixte JTS Paris 2000 is a presentation of traitement des films cinematografiques contamines par les moisissures by Malalanirina Rakotonirainy, Fabien Fohrer, and Bertrand Lavédrine.
15 products are presented to treat mold.
The conclusion is that the best is formalin (4% for 4 minutes).
Perchlorethylene reduce contamination by mechanically removing the mold of film.
Aquasan (5%) followed by washing with water gives a satisfactory result.
Here is an article near you said above.
http://www.clir.org/pubs/reports/pub95/chap3.html Disinfection

Note: there is no universal recipe for treatment of mold.
Depending on the types existing mold on film, a recipe will work better or less effective.

George

Photo Engineer · Jun 28, 2011

B&W film is very resistant to bugs, but it is not impossible to get an "infecton" going on or in your film if conditions are poor enough. Such "infections" are rare enough that they don't trouble most of us. But, Formalin is a good treatment for it, as you say, and a chlorinated hydrocarbon is good for removal.

That is why color stabilizers contain Formalin and why film cleaners used to be chlorinated hydrocarbons.

This has been known for over 100 years, so there is nothing new about it.

PE

cr frank · Jun 28, 2011

Photo Engineer said:
Do you have a URL Frank?

PE

(there was a url link here which no longer exists)

here are the scans of the film in question..

thanks for your input..

charles

Gerald C Koch · Jun 28, 2011

Formalin is merely a solution of formaldehyde in water and a bit of alcohol. Formaldehyde is a gas so once the solution evaporates from the emulsion there is no residual protection against destructive agents such as fungus.

cr frank · Jun 28, 2011

georgegrosu said:
...(cut)
The conclusion is that the best is formalin (4% for 4 minutes).
Perchlorethylene reduce contamination by mechanically removing the mold of film.
Aquasan (5%) followed by washing with water gives a satisfactory result.
Here is an article near you said above.
http://www.clir.org/pubs/reports/pub95/chap3.html Disinfection

Note: there is no universal recipe for treatment of mold.
Depending on the types existing mold on film, a recipe will work better or less effective.

George

George,
Thanks, again, for your interesting comments and i will look into Aquasan as an option.

Photo Engineer · Jun 28, 2011

Guys;

Formalin can attach to the gelatin just as if it were hardening the gelatin. This "poisons" the gelatin as far as the "bugs" are concerned and they shy away. If the gelatin is already infected then it acts as a disinfectant. Either way, the gelatin is cleared of any attraction to or infection by "bugs". It does not entirely evaporate.

As for the spots that started this.... Well, there are so many things this could be I just cannot say offhand, but usually it takes quite a bit of time for "bugs" to create this level of damage. I would therefore suspect a chemical problem. My first observation is that the color is reddish. Iron contamination makes this type of blemish. Red dots. I had this problem until I put in a water filtration system. But, that is just one possible answer.

PE

cr frank · Jun 28, 2011

Photo Engineer said:
Guys;

(cut)
As for the spots that started this.... Well, there are so many things this could be I just cannot say offhand, but usually it takes quite a bit of time for "bugs" to create this level of damage. I would therefore suspect a chemical problem. My first observation is that the color is reddish. Iron contamination makes this type of blemish. Red dots. I had this problem until I put in a water filtration system. But, that is just one possible answer.

PE

I'm sure there will be no definitive answer as to what this problem is. The negs were stored in a very hostile environment for a month.....high heat and humidity. I also live in a 100 year old house with less than perfect plumbing. Even though the water was filtered i have my doubts. My hope is to do what I can to prevent future problems.....at this point that sounds like distilled water and Formalin just for good measure.
Thanks for all the great info.
charles

georgegrosu · Jun 28, 2011

cr frank, Aquasan is a commercial industrial product. He is less efficient than formalin, but does not smell so bad.
Send me an email address where they can send you the scanned article.
George

Photo Engineer · Jun 28, 2011

Charles;

With high heat and humidity, with or without bugs, film will tend to stick together. I believe that if they were not stuck together, then the humidity or the heat was not as high as you think. Generally this type of damage (heat and humidity alone) give irregular patterns of stuck negatives. Add bugs to that and you get softening of gelatin due to bug action. And remember that the original silver metal and hardener will aid in resisting bugs.

I prefer an alternative actor here. But, I may be way off. If formalin alone removes this problem, it was probably bugs. Often, formalin can dislodge the bugs (if any) and still leave damaged film, but just colorless spots.

PE

cr frank · Jun 28, 2011

The film was stored in PrintFile sleeves in three ring binders. Packed in cardboard boxes....i've always wondered how "archival" those sleeves were ??

Photo Engineer · Jun 28, 2011

Almost all of my negatives are stored that way. Some have been there for many years. Stored right with them are contact sheets of the negatives. This is for color and B&W in several formats.

PE

cr frank · Jun 28, 2011

That's good to know....

Gerald C Koch · Jun 29, 2011

To add to my previous post that formalin provides no protection from mold. I have six sets of color slides ruined by mold. The mold hyphae are clearly visible to the naked eye. The slides were commercially processed when a formaldehyde stabilizer was part of the color process.

As far as real bugs are concerned, IIRC, the worst pest is the carpet beetle. This insect is the bane of museums. It appears to be rather general in its eating habits.

Diapositivo · Jun 30, 2011

Gerald C Koch said:
As far as real bugs are concerned, IIRC, the worst pest is the carpet beetle. This insect is the bane of museums. It appears to be rather general in its eating habits.

Can you please elaborate?

Until last October I had my slides processed by a professional laboratory, framed and delivered in plastic boxes, and I kept them in those plastic boxes. No problem so far.

Since last October I develop my film by myself. I keep them in glassine paper sheets inside a ring binder. Worse, most of the time this ring binder is on a bed (with a woollen blanket, I don't sleep there) open to let me easily reach each sheet.

Your post raised some worries regarding this carpet beetle in particular, and small insects in general. Plastic cases were certainly an effective barrier against insects. Ring binders are probably not.

Should I put some insect killer in my cupboard, such as naphthalene? Is there any long-term risk for film?

(When I am rich I will certainly buy some dedicated cupboard, specifically designed for film storage. At the moment I'll to make do with what I have).

Ian C · Jun 30, 2011

According to articles I read in Modern Photography (defunct since 1996 or so) its not the adult insects that are the problem. Its their larvae. The critters love Kodachrome in particular (Ive no idea why). They excavate irregular channels in the gelatin right down to the base.

The Modern Photography articles showed close-up photos of damaged Kodachrome slides that matched some of mine.

The only way Ive been able to reliably prevent fungus (or mold or mildew, whichever it really is) from growing on films is to store the films in Printfile pages in a sealed container with a generous supply of freshly-charged silica gel. The Watertight equipment cases sold by Calumet Photographic (similar to Pelican and Doskosil) have a neoprene seal to keep out water and humid air. It also keeps out insects and their larvae.

I remove the foam padding to maximize the useable volume and add a 750-gram silica gel canister that keeps the interior desiccated. The silica gel canister can be recharged every several years by baking it in an oven at 300F (about 149C) for 2 hours. The canister can be replaced into the case as soon as its cool.

Film stored in air conditioned buildings or in dry environments might never develop mold or fungus due to the moderate humidity. But films that must live in areas of periodic high humidity need extra protection. Insects and their larvae can go pretty much anywhere except a sealed container.

Photo Engineer · Jun 30, 2011

Carpet beetles and their larvae do not prefer film for a feast. So, by the time you see damage from this insect and others, and by the time you see mold, mildew, fungus .. whatnot damage by anything like this, you will see serious damage to other things first. For example, you will probably see mold on walls or on wood surfaces, you will have mold on clothes along with mildew and etc.

So, those that suspect damage to film must look elsewhere to see if there is "collateral damage" going on first, as the film is not the primary attack point, nor the entry point. A damp basement with film stored in it will first show mold on walls and then on film. The mold creeps in via windows, vents and in damp spots and then spreads as it produces spores. It does not, by some miracle, appear suddenly on film. The same goes for carpet beetles. If you have them, then you probably also have a spider problem as the spiders are attracted indoors by the same route as the beetles.

So, if you have NO OTHER DAMAGE, then it is probably NOT mold, mildew, bacteria or carpet beetles.

A case in point is my own. I have an old suitcase filled with negatives nearly 100 years old. Recently, I found one side of it (near the wall) in our basement covered with mold. Inside, the negatives were totally unharmed. Boxes of negatives in another room were unharmed as well. Wiping the suitcase with Lysol was effective in removing the mold.

PE

Gerald C Koch · Jun 30, 2011

Diapositivo,

Carpet beetles larvae will munch on textiles, they will even chew on synthetic blends containing some natural fiber. They can eat the emulsion off photographic materials. I have seen photographs of the damage. I forget at what museum/library this occured. As PE mentioned they do prefer other materials if given a choice. You might want to contact a large museum or the Library of Congress as to what measures to use. Anything you use must be safe toward film and prints. Here in the southern US we must contend with palmetto bugs which can do very serious damge. They are sort of a super roach 1-1/4 inches long. Many people use Franklin Roach Tablets. They contain boric acid with an attractant. They do a good job of killing palmetto bugs. Would these work for other insects? I really don't know.

georgegrosu · Jun 30, 2011

When the mold came on a film there is no treatment that can permanently eliminate these fungi. Treatment with various solutions (eg formalin) of films infected with mold for a time holding back the development of these microorganisms. After this period (smaller or larger depending on storage conditions) and mold growth on the film begins.
By 1980 we used recipes with sodium pentachlorophenol for the prevention and removal of fungi:
1. For prevention:
sodium pentachlorophenol 0.3 g;
ethanol ...........................................20 ml;
watter .............................................80 ml.
2. For removal:
sodium pentachlorophenol 1 g;
ethanol ...........................................20 ml;
watter .............................................80 ml.
Sodium pentachlorophenol is a highly toxic substance that I worked once. I am sure it is really very toxic.
By 1988 we was informed about a very serious accident with this substance (in Czechoslovakia) and then never used us.
George

Formalin to prevent fungus

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