As an artist who works primarily on paper surfaces that need to be framed for protection from the elements, I have long been concerned about using archival materials for framing and handling: museum or rag mats, archival clear wrap for matted work that will be displayed in bins.
But as a young artist starting out, I relied on the expertise of the framers I took my work to for advise on framing decisions. I recently learned from experience that at least one of those framers led me in the wrong direction. In her defense, she might have been giving me industry standard counsel at the time, but I have a piece of art that clearly shows the error of the technique. It is also interesting that there are two pieces, framed in the same way at the same time, and only one of them suffered acid damage. I have to guess that the different rag content of the two printmaking papers caused diverse outcomes.
I am no longer a young artist, and some of my work has been in frames for a long time.
The two particular pieces that I looked at this week were framed about 35 years ago. When I pulled them out of storage to check them out before sending them out on exhibit, I noticed that the glass looked smeared. However, cleaning the glass did not help. I was puzzled about why the inside of the glass would look dirty, but I opened up the frame to clean it.
I found a milky deposit on the inside of the glass everywhere that the black rag mat touched the glass, and the black ink from the print was offset on the glass in the same milky deposit. I am not sure what this is and am not sure it would have been so apparent if the deposit hadn’t been whitish and the mat pure black.
No part of the print was touching any non-archival surface. Behind the print was a 2-ply rag mat that was in perfect condition. The black mat, which was supposed to be acid free (I don’t remember if it was “rag”), was in perfect condition. But the foam core that was used as a backing board behind the 2-ply rag mat “barrier mat” was not an archival material. It was believed that the barrier mat would protect the print from the acidity of the foam core. I can only guess that the damage to the print, and possibly the scum on the glass, was the result of out-gassing of some kind from that foam core backing. The out-gassing, remaining inside the frame package, was able to impact the paper of the print wherever the was air space between the glass and the print. It did not, however, seem to injure the rag mats.
What I noticed next was the shocker. I lifted the mat from the print, to see if the mat was causing an acid burn on the paper. I found that the mat had perfectly protected the paper, but where the mat window was open and the print exposed to the air behind the glass, the paper was burned yellow.
I found it interesting that the second print, framed identically at the same time, did not experience this damage. The glass had the same off-set of the image and the same deposit where the black mat touched the glass. The printmaking paper of the second print has a higher rag content, and apparently was less susceptible to environmental damage.
Needless to say, after cleaning the glass, I replaced the backing boards with newer acid free archival foam core backing boards. And replaced the burned print with a different impression from the edition, which has been stored flat and unframed.
This is one example of what acid damage from non-archival framing might look like. It’s highly unlikely that I will be around to check on them in another 35 years, but I am hoping that current “acid free” and “archival” materials are truly superior to the framing materials and understanding of1981. I have not yet destroyed the burned print. I am thinking about experimenting with it.
Technical notes: The paper that was “burned” was Arches printmaking paper and in the 70’s, I believe it was 40% rag. The paper that did not “burn” with the same framing treatment was Rives BFK, which I believe has always been 100% rag.