Katharine Thayer wrote:
>Judy Seigel wrote:
>
>
>>On Thu, 21 Oct 2004 Ender100@aol.com wrote:
>>
>>
>>>With your oiled negatives, is it possible the oil oxidizes or turns rancid
>>>and cloudy?
>>>
>>>
>>There is this myth that the oil turns rancid, tho I never found it to
>>happen.
>>
>>
>
>My experience with rancidity is that it depends on the oil. The first
>oil I used, a generic vegetable oil from the grocery store, turned
>rancid, and no myth about it.
>
Woa... most vegetable oils will not only turn rancid, but polymerize
with exposure to air -- for example linseed oil, the oil turns into a
yellowed gum. Yes these most certainly "oxidize".
>...
>
>At the first hint of rancidity, I cast about for a better oil and
>settled on mineral oil; I have mineral-oiled negatives that are a
>decade or more old and as fresh today as when they were new.
>
>
It's not just a question of rancidity ... you want an oil that remains
clear and liquid i.e. doesn't develop crosslinks. Mineral oil is pretty
good, but if you expose this to heat oxygen and U.V. I'm not sure how
long it would take to polymerize.
You might try one of the archival fixatives that primarily contain "B72"
such as Lascaux's Fixative (e.g.
http://home1.gte.net/res0a2zt/photos.html). Such compounds have been
well tested and are well respected in the "museum" conservation community.
Jonathan
Received on Mon Oct 25 11:44:55 2004
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