The Importance Of Glassine Envelopes?

Its great that we have a lot of people of the site with a lot of related experience and information...with glassines going for 3,4 and 5 cents apiece..you would like to think they are acid free !!

The following evaluation is from the Northeast Document Conservation Center, with particular focus on paper materials and photographs. Although stamps are not part of this specific evaluation, I think it provides a good summary of what to look out for in terms of use of papers said to be "acid-free" and/or use of glassine envelopes:




For more reading on the subject, you can check it out at this link:

http://www.nedcc.org/resources/leaf...closures.php

Thanks everyone, that is some good stuff and stuff I would have never known. So here is what I gathered then would be a good rule of thumb for me.
1. Current stamps considering that the value would never be all that much, plastic bags would do okay.
2. Glassine that are acid free would be best for older stamps that I want to store away.
3. Stock books for all other stamps that I would like to be able to perserve for a longer period of time.

I think that is a gret start!

Westvaco disappeared as a company some years ago. Are any of its successor entities still manufacturing glassine envelopes? What Westvaco envelopes out there for sale by stockists appears to be old inventory.

I agree with NCBUCKEYE, I also have had stamps in glassines from the late 1960's and there is no effect on the stamps and the glassines have not yellowed or turn brown .This is both for Chicago and Florida climates .

Recently went through some stamps that had been in glassines since the early 1950s, and although the glassines had gone brownish, the stamps were fine. In any case, got rid of all the old envelopes and put into new, as could no longer easily see the stamps inside, along with some ancient glassine interleaving that had turned into a lovely tobacco brown colour...

As this is both my experience, as well as that of others, with stamps as well as covers, may I ask a stupid question?

Q/ Could the glassine envelopes be acting as a sink for sulfur dioxide, et al, thus sparing their contents?

Cheers,

/s/ ikeyPikey (who takes note that of the authoritative posts above, to the effect that shorter fibers in glassine are more reactive)

No one in this thread has any idea if glassines are truly archival. And anecdotal evidence like 'I had some and they turned brown' or 'I had some and they are fine after 50 years' is virtually worthless.

Glassines are a price sensitive item, no one buys 3 or 4 at a time and no one collects them. There is no standard for making them. There is no regulatory oversight during manufacturing of glassines, there is no after market testing. Glassine manufacturers do not perform accelerated aging tests on their products.

What we do know is that there is plenty of evidence that older glassine can and will deteriorate and become acidic. I would agree that environmental conditions an important factor.
I would also agree that most of them are fine for a number of few years IF the proper environmental conditions are maintained.

The problem with glassines, acid free paper purchased at Staples, and preprinted album pages from major manufacturers is that this all marketing hype with no evidence based research or data to back any of it up.
If ANY of these manufacturers had invested the time and money into proper testing they would most surely be touting it in their advertising.

But it is far cheaper to throw a handful of buffer (bicarbonate) into the paper slurry, print 'acid free' on the label, and blame any field reports of acidification on poor environmental conditions.

And while some of us might be careful about how we store the material we have, we have no idea what will happened to it after it passes from our procession.
Don

Enclosing paper in anything is a double edge sword. The enclosure can keep bad atmospheric things away but they can also encapsulate bad things inside.

My opinion is that concentrating on maintaining the proper environment is paramount and to not trust or assume that any of the marketing hype is legitimate. The day that any of these manufacturer publishes real specifications and test data I will change my opinion.
Don

I think we'll be stuck with anecdotal evidence for awhile, but I am a little surprised someone like Palo or Lighthouse hasn't done some proper testing of their products - you would think it could be a selling point to the high-end market?

Anecdotally again in my case, the stamps in glassines had been stored in a "good" environment without excessive heat, humidity or sunlight - for roughly 65 years. I'm sure if they'd been sitting in a damp basement for a significant period of that time, it'd be much sadder story, no matter whether in glassines, 102 cards or albums.

I concur, in the current environment where self printing album pages are eroding market share every year, legacy publishers could have achieved marketplace separation. But it would have meant charging a LOT more than they do now and frankly I am not sure that most collectors would be bothered; they simply would go buy cheap 'acid free' paper at the local big box store and think themselves wise for saving so much money.
None of the philatelic publishers make their own paper; they simply buy it from a paper supplier who makes claims about how it was made. If any of the philatelic publishers test anything then they are certainly not saying a word about the results. Heck, it is hard to even find much anything about their album pages, we are lucky just to get a screen shot of a few pages.
Don

Here are some experts... Society of American Archivists


https://www2.archivists.org/glossar...s/g/glassine






"Hygroscopic" is a characteristic or property whereby the subject absorbs moisture from the air.

Glassine absorbs moisture.

All paper is hygroscopic, it is basically a sponge.

But even more difficult is finding much anything online regarding paper accelerated aging tests. Last time I looked (a few months ago) a could only find a few white papers that were all a number of years old. I found it hard to even find info on how they do accelerated aging testing on paper.
Don

Which leaves us innocent of whether/not this is a good thing.

If glassine absorbs water vapor (or anything else) more readily than stamps, that might very well be the good news.

As Don points out, controlling the environment (including the humidity) is your best first line of defense.

Cheers,

/s/ ikeyPikey (who notes that 'anecdotal' and 'reality' both have four syllables)

102 cards have been mentioned within this thread as an appropriate storage option. My objection to 102 cards is that the adhesive used on 3 sides to attached the foil to the paper degrades over time. I have seen any number of 102 cards where the stamps have lodged into this degrading adhesive. I have no idea is this is a terminal situation or if it may be detrimental to the stamps over time. I always return such lots intact for a refund as I don't wish to find out.

Stamps + adhesive = ummm, no.

Additionally, how many of you have seen the adhesive on the bottom of 102-type cards fail completely, allowing the stamps to fall through the bottom of the card? It may not damage the stamps, but they certainly could become damaged when falling out.