How would you de-fungus a leather case?

[Grytpype]

A few weeks ago I bought a pre-war Zeiss Sonnar 135mm Contax lens, which came in the maker's soft leather 'pouch'. The lens has some fungus, and is currently stored at low humidity until I have time to clean it. However when I have done it and want to try it out, I would be doubtful about using its pouch, because of the risk of re-contaminating the lens.

I have had this dilemma before with several cameras, and have sprayed the interior of their cases with a 50/50 vinegar/water solution, cleaning it off afterwards with clean water and a sponge. I thought I might as well risk some damage on the basis that otherwise the case is useless, though in fact it doesn't seem to have done any harm, in the short-term anyway.

However the Sonnar case is leather inside and out, and in very nice condition, so I don't think the vinegar treatment would be effective without soaking it in the stuff, which I am certain would be a very bad idea!

I have seen suggestions on this forum that moth-balls will kill fungus, though I was sceptical at the time. I've been doing some searches recently, and find mostly rather vague suggestions that moth-balls may prevent mould from developing (as opposed to killing existing mould). The most positive source I have found so far is this one, however the Wikipedia entry for naphthalene makes no mention of any anti-fungal properties. Does anyone have access to any really reliable information (as opposed to online non-scientific DIY-type sites) that confirms the effectiveness of naphthalene/moth-balls against fungus?

Another possibility is that exposure to ozone appears to be a proven means of killing mould, but I'm not sure if the 'air purifying' type of generator, which are easily obtainable, would produce a high enough concentration, or if the ozone would have any ill effect on the leather.

Does anyone have experience of successfully killing fungus with either of these methods?

[Steve Roberts]

For killing fungus in lenses and on old slides I use carbon tetrachloride (p a u s e for Health and Safety Police to jump in!) . Usually the fungus returns on lenses sooner or later, but of course I never know whether that's the original fungus that wasn't totally killed or whether it's a new outbreak. Carbon tet. used to be used in dry cleaning, so I wonder whether it's replacement would help if you sent the pouch for dry cleaning? The cleaners should be able to advise on any potential ill effects on the leather (I have no idea). Of course, the main thing in coping with any fungal problems, whether relating to lenses, leather or, indeed, Athlete's Foot, is to keep the environment as dry as possible! Not easy in the UK.
Good luck!
Steve

[E. von Hoegh]

A weak solution of copper sulphate.

[cowanw]

Beg a hospital staff member or your Family doc (in a small town) to gas sterilize the case when they are doing another job. (not steam)

[KenS]

A dilute solution of Thymol.

Ken

[Grytpype]

Thanks for the interesting replies!

I didn't know it was still possible to get hold of carbon tetrachloride, Steve. I think aggressive solvents are supposed to be bad for leather, since they can wash out the natural oils, but it might be worth further enquiries. I also didn't know copper sulphate was a fungicide, but I see from searches that it is used in 'Bordeaux mixture' to control fungus on grape vines.

I had hoped to find something that does not involve soaking the leather in liquid, and the last two suggestions might well do the trick. Thymol looks extremely interesting and not difficult to get hold of. It seems to be pretty harmless ("an active ingredient in food flavorings, perfumes, cosmetics and mouthwash"), and apparently the crystals evaporate slowly, so if I just put the case in a sealed container with some Thymol it might well do the job.

Thanks again,

Steve.

[keithwms]

I wonder about putting it in a container with a burning sulfur stick, the kind they use for treating wine barrels.

[MDR]

A bath in pure alkohol 96% or in every good desinfectant (Hospital) should get rid of fungus. Use something like Lexol or other leather care products to clean and wax the bag after the treatment. Incense is know to kill all kind of germs including fungus.

Dominik

[keithostertag]

I wonder if putting it in the microwave will kill fungus? Of course it won't remove the dead fungus- you would still need to clean it... Anyone know if that would work?

[cowanw]

Microwave will shrink it to fit a Barbie Doll camera.