>> Just be aware that glassine envelopes are a far cry from archival by
>> today's standards. Conservators have advised against them for at least
>> 30 years now.
>Ryuji responded:
> What's the basis for this? In my understanding, "archival" glassine
> envelopes sold for photographic use these days are lignin- and
> acid-free, like other archival paper envelopes. However, I didn't
> confirm this with a glassine manufacturer. Did you?
==========
I tend to agree with you, Ryuji. How many people buying archival materials have looked at the data and confirmed that this or that is good or bad for their photographs? It is natural to assume that when a company like "Light Impressions" sells something as being archival, it is probably archival because their reputation precedes them.
Then again, sometimes I think some sellers really do not know for sure.
I would argue that some materials might contain acids and still be acceptable for storage. I would also suggest that some people using glassine for long term storage might be using something LI does not know about. LI cannot know everything. It is likely that there are some extremely high quality materials out there on the market.
It is also possible that degradation is due to poor processing and not the glassine or Kraft envelopes. Or they are concerned when their glassine starts to yellow, which may or may not indicate a problem.
As for the comment about what conservators have advised or not advised for 30 years, you can find confirmation that these conservation experts are correct. You can also find information that goes against what some of them say. I found one conservation expert that says egg yolk must never be added to inks because it degrades. Tell that to the St. Johns Illuminated Bible Project people.
You can refer to specialty groups like I belong to that will tell you that yes, glassine is good; in some cases, no, glassine is bad. All I can do is use my own experiences to determine something that might not apply to the next guy. If I guess wrong, it is my problem down the road and my Zeppelin issues will be lost forever.
Some reputable collector organizations have tested various products and discovered they can vary in pH balance. I suspect it is the same with archival products sold to photographers.
Bob
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Received on Mon Feb 13 14:40:15 2006
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