[Alt-photo] DOUG ISHIMURA, IPI re: DOES LIGNIN CONTENT IN PAPER KEEP IT FROM BEING ARCHIVAL?
bobkiss at caribsurf.com
Tue Jan 16 01:42:42 UTC 2018
Below is info from Doug Ishimura of IPI on lignins forwarded with his permission:
Lignin has been a very big issue in the deterioration of photographs. Even the Fading Committee of 1855 noted that poor quality mount boards were a cause for fading photographs.
In the 1960s and again in the 1980s, lignin from poor quality cardboard microfilm boxes were implicated in the formation of red spots or redox blemishes on microfilm. These spots are a form of silver image deterioration. As it turns out, the lignin, a complex, undefined organic molecule, generates peroxides as it breaks down. It also produces molecules that are referred to as chromophores that cause staining of the gelatin and albumen in photographs.
Peroxides are bad because they can remove electrons from silver converting image silver to mobile, silver ions (silver oxidation) and can provide electrons to convert silver ions into elemental silver atoms (reduction). This wouldn’t be a problem if both events occurred immediately together, but they don’t and the silver ion has plenty of time to migrate away from the silver image particle where it originated.
The result that we see is yellow/orange/red staining of highlights and mid-tones, silver mirroring, fading, and red spots.
The photographic activity test in ISO 18916, which is required in the enclosure standard, ISO 18902, looks for both staining of proteins such as gelatin and albumen and silver particle oxidation or reduction.
From: bobkiss caribsurf.com [ [ mailto:bobkiss at caribsurf.com | mailto:bobkiss at caribsurf.com ] ]
Sent: Monday, January 15, 2018 11:26 AM
To: Douglas Nishimura < [ mailto:dwnpph at rit.edu | dwnpph at rit.edu ] >
Subject: DOES LIGNIN CONTENT IN PAPER KEEP IT FROM BEING ARCHIVAL?
Does lignin content in paper keep it from being archival? I seem to recall that we used 100% cotton paper for our hand made prints because it was lignin free.
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