Exposures and "Archival Survival"

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Jana

SGF, Supreme Grumble Framer
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Mansfield, Ohio
A customer brought in 2 frames with mats from Exposures. She needed the mats recut. OK, OK, so I did it and charged her. She's usually a pretty good, regular customer. So she went to the dark side this time.

The point is that there was a sticker on the regular mat board backer. It said "Archival Survival - We only use acid-free matboards and backboards."

Now isn't that misleading? I explained to her that, no, they were not using archival materials and showed her the difference. Also, the face paper on the regular paper mats is not acid-free. It's like when Martha Stewart gives misleading advice about framing, but that's another topic I'll pursue later.
 
Yes, it's misleading and another good reason not to use the term "acid-free" unless you're referring to someone who got through the 60's without an LSD experience.

I visited an Exposures outlet about 25 miles from here a few years ago in Oshkosh. I'm nearly certain it's a division of Miles Kimball. I've never seen so many popped-corner frames, ragged mats (instead of rag) and just all-around crap in my life.
 
It's my understanding that so-called "acid free" mats are not, really. The paper's acid-bearing component that causes the damage, lignin, is in the paper all along.

Here's the explanation I've heard from a couple of paper experts: The pH of wood pulp board is "adjusted" with the addition of a high-alkaline buffer (calcium carbonate, the main ingredient in most stomach antacids) during manufacture. That makes the board test as alkaline on the pH scale. But over time, the buffer is used up as the lignin generates acid. When the buffer becomes exhausted, then the discoloration takes place.

To put it another way, the board is high-alkaline when new, then creeps toward pH neutral, and continues to degrade into the acid end of the pH scale. The lignin isn't removed, its effects are simply delayed.

How long before discoloration happens? That depends on the amount of lignin in the pulp, the manufacturing tolerances, and the environment of the board throughout its lifetime. Maybe ten years, maybe twenty, but it varies.

If anyone has another explanation of "acid free", which sems to be a tragic misnomer, please speak up. I'd like to learn more about this.
 
I forgot to say that the best boards are not only acid free, but also lignin free.

That would be alphacellulose, which could be cotton linters, or purified wood pulp, or some combination of lignin free pulps. And most of those good boards are still buffered, to offset the migration of acid from external sources, such as free air or a wood frame's rabbet.

The U.S. Library of Congress has recognized and approved (only for its own uses) both 100% cotton boards, and purified wood pulp boards which are free of lignin.

I never weas very good at chemistry. :rolleyes:
 
Jim, I've done a great deal of reading and research into this very subject, and you are right on, from what I've read. What I had learned in Materials and Methods of Construction about woods and wood products, I could not reconcile with what I was reading about what was going on in mats, hence the research, and reading everything that I could lay my hands on.
Regular mat boards are wood products, and just are buffered. They are simply a delayed acid product, as Jim says. If you want truly acidfree products, you have to get a product that has no wood content in it to start with, which is why we use rag mats for conservation. It is made of cotton linters, and there is no wood in the pulp from the get go. This is the only way to have a completely acidfree product.
 
Sorry, fttom, but you sound like a Crescent consultant.

We need to make a distinction between "buffered," which is temporary and "purified," which is not.

I believe purified alpha-cellulose boards (e.g. Alphamats) are the c/p equivalent to 100% rag boards. I also believe it is likely that, with the addition of Zeolite/Artcare technology, the Alphamats may be superior.

That being said, I happen to like the look of solid 100% rag with a matching core. (You can get those as ArtCare, too. ;) )

I also realize that about 40% of the people reading this will agree, 40% will disagree and 20% will say, "Huh?"

This is an issue which has continually threatened to derail the efforts to revive FACTS.

And let's not lose sight of the fact that those Exposures mats are neither rag NOR purified alpha-cellulose. They are buffered pulp boards.
 
Ron, from what I've been able to find out about the Zeolite technology, all it does is postpone the inevitable. I've looked into this specific thing, because I read the word Zeolite, and had no clue as to what this stuff was. Apparently, eventually, the Zeolites will be used up, and you are left with an acid product. They can only put so much of the Zeolites in the mix, and they don't last forever. Honest, I'm not trying to be my usual difficult self. I,too, like the look of the alpha-cellulose boards, and that's why I was doing all of this research and reading. I wanted to understand why it wasn't as good as rag. Now, it may take 50 or more years to use up all of the Zeolites, but, eventually the acid eats them up, and then does it's damage, anyway. Which I think stinks, personally, but that's what I've found. I'm open to further research, if someone will point me in that direction. I'll certainly go there.
 
Susan, you and I both have things to do, but this is important. It may be the most critical c/p issue in our industry at this time.

<U>Purified</U> alpha-cellulose boards do not become acidic if or when the Zeolites run out. There is no internal source for acids. The Zeolites are a "bonus" to help protect the art from environmental pollutants - something 100% rag cannot do alone.

Alphamats do not rely on Zeolites to neutralize or buffer acids in the board. The lignins are removed and the boards - without Zeolites - are as permanently "acid-free" as 100% rag. You don't have to believe in Zeolite technology to accept this.

Many of the people who have strong feelings about this one way or another work for Crescent or for Bainbridge. I don't work for anyone - though I sometimes wish I did - and I use approximately equal quantities of Crescent and Bainbridge product with some Tru Vue and Artique thrown in for variety.
 
Tell me where to go to read more, Ron. You've seen some things that I haven't, and I want to read them. Like I said, I'm not trying to be difficult. I'm trying to understand this stuff. I know you're on the FACTS committee, and you've probably seen some papers that I haven't. Tell me where to go to read stuff.
 
Sue, Ron's right. I don't have time to hunt out references right now, but if you go to Conservation On Line (CoOl), I'm sure you'll find links to the right places. There is also a Google search engine on CoOl, but you have to poke around to fine it.

Rebecca
 
Just reading your Bainbridge specifier may give you the information you need. It is worth the effort to study these materials, perhaps with a dictionary at hand.

Perhaps you are confusing the validity of buffering --- not of adding zeolites -- as there has been considerable argument that buffered papermats will eventually turn acidic as the buffering wears out, or gets full or whatever!

As you most likely have heard, "Artcare" means the zeolites have been added and that is Bainbridge's trademarked name and process. The primary purpose of Zeolites has little or nothing to do with maintaining neutral PH.

That is the job of buffering (usually with calcium carbonate).

The specifier clearly shows which products are "ARTCARE".....and their papermats do not advertise zeolite additives. It also says which one's are lignen free from wood pulp and which ones are lignen free from rag. (Pure alpha celulose MEANS lignen free)

It also shows which ones are buffered to help maintain neutral PH in any environment (practically all, by the way by both BB & Crescent---in both paper mat, rag mat and alpha mat lines)

I don't know of any other company adding zeolites to their mat board or framing related products. Does anyone?
 
I'm not sure I want to add more fuel here, but Ron's right.

Alphacellulose is paper pulp that has no lignin -- whether it is inherently lignin free, such as 100% rag (cotton) or purified of lignin content, such as Bainbridge Alphamat & Crescent Select (and others).

Some framers say that 100% cotton is better, and others say alphacellulose is purified pulp is purified pulp is alphacellulose, no matter how it started out. The U.S. Library of Congress has tested and approved both cotton & purified pulp as being equal for their purposes. That's good enough for me.

The zeolite thing is still too new to know how long the additive will last, but accelerated life tests have shown the additive to outlast contamination that would be extreme in any frame. As Ron said, the Bainbridge zeolite-equipped boards are alphacellulose (lignin free), so only contaminants external to the board -- airborne, or from other materials within the frame package -- are a concern for the zeolite's passive trapping action. In any case, zeolite in matboard is almost certainly an advantage, and with no suspected drawbacks. Still, some say there's no need for that kind of additive in a matboard; for preservation purposes, the fewer chemical components go into a frame, the better. Who's right? We should know within a hundred years or so. Place your bets ladies and gentlemen.

Technically, cotton and purified pulp are equal for framing purposes, IMHO. But regardless of that, everyone has their preference, mostly based on texture, or feel, or handling, or the way the board cuts.

At a recent trade show an experienced and very knowledgeable framer (almost conservator) and I were discussing this topic on the shuttle bus. He said there's a distinct difference in the coefficients of expansion between cotton and purified pulp. That is, cotton expands and contracts more (and faster) when humidity conditions change. Purified pulp boards are more stable; they react less (and more slowly) to environmental changes. He couldn't find any lab tests for that, so he created his own test using 40" strips of board, adding and subtracting moisture from them in a controlled environment, and measuring the changes in their length. I'm not sure, but I think he said there was a difference of more than 20%, which would be significant.
 
All very interesting information, Folks. Seems like I need to do some more reading. I do read the specifiers, but that's not where I read that the zeolites will wear out. Can't remember where I did, and I've got to find it, and read it again to be sure that I didn't misunderstand it. When I do, I'll get back to you. In the meantime, I'm going to Rebecca's site, and do some more reading. I'm always willing to learn more.
 
Can't remember where I did, and I've got to find it, and read it again to be sure that I didn't misunderstand it. When I do, I'll get back to you. In the meantime, I'm going to Rebecca's site, and do some more reading.
Click to expand...
You really don't have to get back to us, Susan, we've had knock down and drag out fights over this and we don't need to go there again....for the sake of the G. The info Ron and others gave is flat out the dead solid perfect truth. ;)


Maybe if one of the matboard companies comes out with new technology we can climb back on that horse.
 
Jo, what you don't understand, is that I probably got other information from the same source, and, if this was wrong... You see my point. I'm not trying to beat that dead horse, again. It just makes me crazy when I think I've got something down pat, find out that it's not, then can't remember/find where I read it. It makes me question everything that I've read on that subject. Since I'm studying very hard this year for the CPF, I want all of my reading and information to be correct. I have got to find where I read that, and see what else is in that book/magazine/aritcle/webpage, so I can correct whatever else I may have been misinformed on. I hate being wrong!
 
Or outposted.
 
Susan -

I did do some perusing and came up with the following info, that you and others may (or may not!) want to read.

In very brief summary, the answer to your question is yes, zeolites can become "filled up", and so be unavailable for further adsorption of pollutants. Zeolites also adsorb water vapor in preference to pollutants, so its best keep your ArtCare dry (maybe even a sealed framing package if you're in a humid area).

I myself was wondering if zeolites could "off-gas" after they're filled, but apparently that only happens at very high temperatures (e.g. 250 degrees C) so I won't worry about that one anymore!

What are zeolites?
http://palimpsest.stanford.edu/byorg/abbey/an/an20/an20-7/an20-702.html

Remple WAAC article – are zeolites effective in protecting art?
http://palimpsest.stanford.edu/waac/wn/wn18/wn18-1/wn18-106.html

post re reversibility of zeolites (can release water/pollutants at 250oC)
http://palimpsest.stanford.edu/byform/mailing-lists/cdl/1999/0682.html

Biography of James William Barrow, describing his role in paper permanence – a good history of the “permanent paper story”
http://palimpsest.stanford.edu/byauth/roggia/barrow/

google search on CoOL
http://palimpsest.stanford.edu/search.html

Oh, and for Jana's original thought about what I call the phony acid-free paperboards, this from the Institute for Standards Research, 1994 (copied from a conference review in the Alkaline Paper Advocate, Dec. ‘94)

From the first order reaction kinetic model, some evidence was found that the deacidified groundwood papers had a higher relative deterioration rate than the deacidified woodfree papers. Therefore care has to be taken using lignin-containing materials.

Rebecca
 
Thanks, Rebecca! Actually, I had gotten into the CoOL site last night, and read some of these very things. It is really interesting. I've still got to find out where I read the other, though, it's making me crazy.
Actually, when you give us these references, I'm going to them, printing them, and putting then into a notebook for further/future study. I'll get all this down yet!

Framerguy, be nice. I didn't step on your toes, but once, and didn't mean to then. :eek:
 
Check out all the work done on this matboard controversy on the FACTS web pages at www.artfacts.org go to "Standards" then almost to the bottom of the list to "PMMB-2000" Why reinvent the wheel - as Ron says "Get the FACTS"
 
Going there, right now, Greg. I'm collecting a whole notebook of info on this topic. My thanks to you all. I'm learning a lot here. I love it when I stir things up and all ya'll hop in to tell my how wrong I am, and I get all these neat new places to go for references to learn something new. :D
 
This is another example of a thread that has turned into a great informational tool. There are
a few additions that may help. The zeolite used
in N/B board is organophilic and hydrophobic.
That means that they are engineered to take up
organic molecules and to avoid loading up with
water, which would render them ineffective. Their
useful lifespan will depend on the environment in
which they are stored, but it should be longer than the 20-40 years that a mat should be in service.
There are two issues that should be considered in
choosing mat board, one is potential acid output
and the other is donations from lignin. We know
that acid breaks the cellulose chains and weakens
the board. Lignin gives off peroxides as it degrades and this does cause color change in
paper, but I have not been able to determine whether it causes significant weakening of the
paper. Discoloration must be avoided and so the
best material has no lignin, i.e. cotton. When
wood pulp is purified, it should have so little
residual lignin that it will cause no change and
can be safely used in place of cotton as the
Library of Congress has indicated. The only problem is the one Jim pointed out; the use in
C/P settings of board made of fiber from which the lignin has not been removed, to which calcium carbonate has been added. While the CaCO3 may counter act the acids that the board produces, it is unlikely to interact with peroxides. Research at the Nat. Instit. for Standards and Testing showed that CaCO3 does not react with oxides of sulfur and nitrogen.
Framers are very lucky to have a huge variety of
boards that are lignin free and buffered so that
they can give steady, non-donor support for decades.

Hugh
 
"Lignin gives off peroxides as it degrades and this does cause color change in
paper, but I have not been able to determine whether it causes significant weakening of the
paper." (Preservator)

If lignins don't cause weakening of the paper, do you have any idea what does?

In our sample box, we have examples of different types of matboards, including some old, brittle ones. I like to show the "acid free" paper mat that has buffers in it. It's about 10 years old. Its very dried out and cracks when I bend and break it. I think this demo scares a lot of customer away from wood pulp mats!
 
The tennic,formic and acetic acids that come form
wood can certainly weaken paper. Alum rosin sizing
may be an even greater source of acid. Oxides of
nitrogen and sulfur are acid percursors and
in combination with atmospheric water they can create nitric and sulfuric acid (as they do in acid rain). As soon as paper is made, its pH begins to drop. That is one reason that the inclusion of calcium carbonate is so useful in extending the life of paper and board. I wish I had a more definitive answer about whether peroxides can break cellulose chains and I continue to ask those who are better informed than I (conservators, conservation chemists, and
technical folks from the paper industry) but so
far, I don't know. I have been told that it causes
darkening and that alone is enough to require its
exclusion from preservation quality materials.

Hugh
 
Hi Jana -

Your cracked and brittle matboard sample is the one that's lignin filled and loaded with carbonates? The so called "acid-free" papermat? If so, I bet Bob Carter would be interested in hearing about that, because he's been looking for studies about the aging characteristics of that type of board. This is the perfect "natural aging" test!

I think what Hugh meant is that as lignin breaks down, it produced acids and peroxides. The acids weaken and break down cellulose, while the peroxides cause discoloration. The peroxides may also weaken cellulose. It makes sense that they would cause weakening - hydrogen peroxide bleach does too. Peroxides also cause little red spots to appear on microfilm, and create problems with silver gelatin photographs. Photographs are a bit like canaries in the mineshafts - that's why photographic enclosures have to be so pure.

Rebecca
 
Thanks, Rebecca. I is the first time I have heard
anyone say that peroxides do break cellulose chains. I suspected that it would happen
for the reasons you mentioned, but am only willing
to state what I have heard from the better informed, such as yourself.

Hugh
 
Thanks Hugh for the zeolite info - that makes me feel better about the high humidity scenarios!

I'm sure I'm right about the peroxides, but I always feel more comfortable when I can document my beliefs - will look for published info so I can cite lofty references when making sweeping statements!

Rebecca
 
Wow, I am so impressed. All of this talk about acids and zeolites and cotton and purified wood pulp. Makes my heart beat fast to see so much good info coming over this forum. Really wonderful!!

Keep up the good work!!

Nona Powers, CPF, GCF
www.nonapowers.com
 
Hi Nona - nice to hear from you again!

Just to wrap up the peroxide question (for those who are biting their nails and sitting on the edges of their chairs!), peroxides break down to release oxygen, which is a very reactive chemical. It reacts with the -OH groups on cellulose, turning them into aldehydes and acids, breaking sugar rings and molecule chains as it does so.

Rebecca
 
Now, see there? And you all just thought I was making trouble, as usual. See what we've all learned? I do so enjoy getting everyone's juices up!

Seriously, thanks for all of the great info. I've been doing some really great reading here, and learned lots. Thanks!
 
In the current issue of the Journal of the American Institute for Conservation,Vol. 41, No.3, Daniel Burge, James Reilly, and Douglas Nishimura report on testing done at the Image Permanence Institute on papers and boards that may be used in the storage of photographs. Since photos are some of the most reactive subjects, they are a good indicator. IPI has developed a widely used test called the Photo Activity Test, P.A.T., and boards that have passed that test can be safely used with high degree of certainty. They found that the addition of calcium carbonate did reduce staining from low lignin boards, but high lignin boards failed their tests, even when they were buffered. They conclude that "Fully deliginfied Wood-pulp papers should be as safe as cotton papers for the storage of photographic images. Since "acid-free" only refers to the current pH of the paper and can be so widely applied that it somewhat useless, it is safer to look for boards and papers that are lignin-free (i.e. they have or can pass the phloroglucinol test) or have passed the P.A.T.

Hugh
 
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