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Lars
Tinkerer Username: Lars
Post Number: 5 Registered: 09-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 22, 2013 - 04:28 am: |
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This may already be known to some of You, but I think it is worth repeating anyway. The message is: You should never ever store Your photographic treasures (be it film, negatives, slides, prints or cameras and lenses for that matter) in a cabinet/cupboard or any other type of furniture made of fibreboard. The reason: All types of MDF contains formaldehyde. It is a part of the manufacturing process. This formaldehyde slowly evaporates over time, and will eventually attack negatives, slides and prints. It sort of restarts the developing process and the pictures will gradually fade away forever. Once it has started it is very hard to stop. Removing the material from the storage in question is of cause the first step. A thorough rinsing and drying may also slow down the degradation. But be careful, old photographs are very fragile. Further more: When formaldehyde mixes with the moisture in the air, it forms formic acid. This is an even nastier substance, because it will attack and corrode most metals, lens coatings and even the glass it self. Brass and aluminium are particularly vulnerable. Chromed or nickel plated surfaces will resist a litte longer, but black paint will crack and lift of. Older Zeiss lenses with so called T-coating are very sensitive but newer coatings are also at risk. So, what can be done? Not much really. You can not air it out. The fumes will always return as long as the fibreboard exists. Nor should You attempt to cover it with paint. A layer of paint will only introduce further harmful chemicals (Perhaps I should add that veneers or plastic coverings are no protection. The formaldehyde will get through). My recommendation is simply that You move Your stuff to a storage made of solid hardwood or metal. Clean all cameras and lenses thoroughly and leave them out to dry. And, while we are on the subject: Plastic bags made of PVC or PE are not ideal for storing cameras and lenses. The plastic contains solvents and softeners that will eventually migrate over to (and ruin) whatever is stored in them. Use paper bags instead. |
Glenn
Tinkerer Username: Glenn
Post Number: 1081 Registered: 07-2006
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 22, 2013 - 09:41 am: |
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I certainly would not use paper bags - unless they are certified as Archival Grade. Cheap paper for bag production can exhibit an acidic pH value. Archival nylon or mylar bags containing a properly activated silica gel moisture removal pack is the best way to go - certainly for storage of photographs and slides/negatives Unfortunately MDF is not the only wood product that uses phenol formaldehyde based adhesives and bonding agents and formaldehyde is likely to be detected in all modern housing, or habitations containing modern furniture. However detected levels are usually very low and much of what is on the internet is alarmist and misleading to say the least. The formation of formic acid from moisture in the air can obviously occur - it is a sound and known chemical reaction. However, for this to damage photographic equipment one would have to store the equipment where large amounts of condensation can occur and the high moisture content would be the major damaging factor, not the concentration of acids formed. I will also point out that coating with oil based paints is an industry standard for sealing phenol formaldehyde bonded wooden sheeting/fibre boards. Having been involved with photography and all types of chemicals for all of my working life, the migration of plasticisers from plastics and vinyls used post 1960 is the biggest destroyer of photographic equipment stored under the wrong conditions. |
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