Plastic or metal storage canister?

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brassplyer@yahoo.com - 29 Sep 2006 06:47 GMT

I have a number of 8mm films, many of which are over 40 years old. Some
are spliced together on 400ft reels and have been sitting in metal cans
for most of the time, a few are on 50ft reels and have been in the
original plastic cases, a few are just in paper boxes. Except for a
couple that got some crud dripped on them in the refrigerator (now kept
in a plastic box after cleaning with Film Renew), they all seem to be
in good condition, bright color etc. I believe all the film my Dad shot
was Kodachrome, don't know if this is significant.

A film supply company I've been buying items from tells me they
recommend vented plastic storage cans to avoid vinegarization of the
film. Hasn't been a problem so far but any opinions on this?

Thanks.

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Marvin - 29 Sep 2006 16:31 GMT

> I have a number of 8mm films, many of which are over 40 years old. Some
> are spliced together on 400ft reels and have been sitting in metal cans
[quoted text clipped - 10 lines]
>
> Thanks.

Most plastics contain compounds called plasticizers, which
can leak out as vapor and damage film. Metal containers are
safer for long-term storage.

The purpose of venting is to keep the vapors from
accumulating. But the vents will also allow gases and
vapors ot enter the tsorage container.

I don't remember ever hearing or seeing the word
"vinigarization", and can't find it anywhere. I wonder what
it means.

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lucasea@sbcglobal.net - 29 Sep 2006 18:08 GMT

>> I have a number of 8mm films, many of which are over 40 years old. Some
>> are spliced together on 400ft reels and have been sitting in metal cans
[quoted text clipped - 12 lines]
>
> Most plastics contain compounds called plasticizers,

Not really. Some do, but by no means "most". Depends on the application.
Plasticizers are generally only used in things that are highly flexible
(think shower curtain, for example), and most often in PVC, since it's so
brittle without being plasticized. The film storage containers I've seen
are either HDPE or LDPE, which are almost never plasticized, particularly
when used in rigid applications like a storage case.

> which can leak out as vapor and damage film.

Don't you think the film manufacturer would've taken that into account when
choosing a container?

> Metal containers are safer for long-term storage.

Doesn't rust and other metal corrosion stain and chemically attack film?
For example, over time, metal oxides could catalyze depolymerization of the
celluloid film, or deacetylation. Seems to me that good pure plastic would
be a better answer.

> I don't remember ever hearing or seeing the word "vinigarization", and
> can't find it anywhere. I wonder what it means.

Umm...perhaps generation of a vinegary smell due to hyrolysis of acetic acid
from the cellulose acetate? You could find it if you spelled it right.
Most of the hits I get refer to the vinegarization of wine, and I hadn't
heard of it happening to old photographic film, but it seems plausible.
Presumably it's autocatalytic, since the acetic acid will both attract
moisture and catalyze the hydrolysis reaction. Venting of the vinegar would
slow down the autocatalysis.

Eric Lucas

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Marvin - 30 Sep 2006 16:24 GMT

>>>I have a number of 8mm films, many of which are over 40 years old. Some
>>>are spliced together on 400ft reels and have been sitting in metal cans
[quoted text clipped - 24 lines]
> Don't you think the film manufacturer would've taken that into account when
> choosing a container?

Surely, but they aren't thinking about long-term storage.

>>Metal containers are safer for long-term storage.
>
> Doesn't rust and other metal corrosion stain and chemically attack film?
> For example, over time, metal oxides could catalyze depolymerization of the
> celluloid film, or deacetylation. Seems to me that good pure plastic would
> be a better answer.

No sign of rust in my metal storage bins.

>>I don't remember ever hearing or seeing the word "vinigarization", and
>>can't find it anywhere. I wonder what it means.
[quoted text clipped - 6 lines]
> moisture and catalyze the hydrolysis reaction. Venting of the vinegar would
> slow down the autocatalysis.

Search engines (e.g., Google) and an online dictionary I
used suggest alternate spellings.

> Eric Lucas

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lucasea@sbcglobal.net - 30 Sep 2006 20:46 GMT

>>>Most plastics contain compounds called plasticizers,
>>
[quoted text clipped - 12 lines]
>
> Surely, but they aren't thinking about long-term storage.

Why not? They know perfectly well that people store films for years, as
does the shopkeeper that made the recommendation. Not everybody makes
decisions based only on short-term profits--some people actually make
sensible recommendations based on doing the right thing, simply because it's
the right thing to do.

In any case, the reality is that the plastics used for those bins do not
contain plasticizers, so your theoretical point is worthless.

>>>I don't remember ever hearing or seeing the word "vinigarization", and
>>>can't find it anywhere. I wonder what it means.
[quoted text clipped - 9 lines]
> Search engines (e.g., Google) and an online dictionary I used suggest
> alternate spellings.

That's as may be, but the fact is that within 2 seconds of launching Google,
I had several hundred links to pages that discuss the word vinegarization.
Since the only difference between my search and yours was apparently the
spelling, I will repeatmy original, correct, statement: you could have
found it if you had spelled it right.

Eric Lucas

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