Archival quality of RC printing paper

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Are there any known facts about whether FB paper has more archival qualities than RC apart from the fact that FB has been with us a bit longer? Also I print 16" x 12" prints on RC Ilford Warmtone Paper and mount them on foamboard before cutting a mat and framing. My question is will the plastic backing of the print put up a barrier against any contaminants from the foamboard? Also a print in a mat and sealed behind glass is a good protection against the atmostphere. Thanks Ian

-- Ian James (ianjphoto@ndirect.co.uk), October 17, 2000

Answers

The latest findings (people always argue about "facts") are that RC paper must be completely toned in selenium toner or a sulfiding toner in order to be expected to be around a while, and that sealing an rc print in a frame can cause much more of a problem than it solves becauses it traps gases from the titanium dioxide brightener inside the frame.

See _Post Exposure_ by Ctein for lots of info about rc paper problems.

Later info from Ctein and Douglas Nishimura of IPI is that selenium toning needs to be done with at least 1:9 strength for at least two minutes, or the print should be toned to completion, and that this can be expected to make an rc print as "archival" as it's going to get. The old idea of toning a print in weak selenium toner as "protection" doesn't work any more; it does pretty much nothing. The reason is that the sulfiding agent that used to be present in Kodak selenium toner is no longer added.

Toning in a sulfiding toner such as Kodak Brown toner, Polytoner or Agfa Viradon works.

Ctein has found that Agfa Sistan affords protection from staining and blemishes, while Nishimura warns that since Agfa will release _no_ documentation proving that Sistan actually works Agfa's claims should perhaps not be taken for granted.

The above specifically addresses blemishes, spots and "silvering-out" that's caused by gas from the titanium dioxide paper brightener itself; with rc paper it's a case of the material itself carrying the degrading agent.

The same toning procedures are applicable to fiber paper as protection from contaminates etc, but since the brightener isn't used in fiber paper at least there isn't that concern.

RC paper also has a history of support problems, with the paper base itself developing cracks with age.

So...based on all that, I'd say that untoned fiber prints will most likely have a _much_ longer life span than untoned rc prints. People have reported that untoned rc prints in frames have silvered out in a matter of months, and it's _not_ a case of processing error.

Toned fiber prints will most likely have a much longer life span than toned rc prints simply because the paper base doesn't degrade in light like plastic does.

Another point of concern is foamboard; it's usually not considered archival at all, and gasses from it may cause problems.

-- John Hicks (jbh@magicnet.net), October 17, 2000.


Does Ctein and Nishimura's data -- 1:9 & 2 minutes -- apply to fiber as well? I usually follow Kodak's recommendation for non-tone- changing toning and dilute between 1:20 and 1:40 and leave my prints in the toner for at least 6 minutes.

-- Christopher Hargens (ldmr@cruzio.com), October 17, 2000.

Dr. Nishimura's paper of 1988 is at:

http://palimpsest.stanford.edu/byorg/abbey/an/an12/an12-5/an12-507.html

This year he passed along the recommendation of selenium toner at least 1:9 strength for at least two minutes via Richard Knoppow in rec.photo.darkroom; presumedly it's applicable to both fiber and RC.

Lately he's been active in rec.photo.darkroom, so probably if you post your question there it'll be answered in more detail by him or Richard. Richard posted a several-part message from Dr. Nishimura a couple of months ago; it could probably be found on dejanews by searching on Knoppow or Nishimura in rec.photo.darkroom within the past six months.

-- John Hicks (jbh@magicnet.net), October 17, 2000.


John, thanks so much for that fine & detailed and insightful discussion on RC paper. Best one I have read.

chris

-- Christian Harkness (chris.harkness@eudoramail.com), October 18, 2000.


When enquiring about Sistan some time ago I have in fact received the abstract of an article by one of Agfa's scientists stating that the effective agant in Sistan is thiocyanate which is supposed to precipitate back any silver that might be created by the action of light or radicals, thus avoiding silvering out.

-- Thomas Wollstein (thomas_wollstein@web.de), October 18, 2000.


The objection to Sistan is that Agfa hasn't published or made available any test results that show Sistan actually does what it's claimed to do.

There's really no argument that it should work exactly as claimed, just the question "does it?"

-- John Hicks (jbh@magicnet.net), October 18, 2000.


The only tests I know of so far are those by Ctein, as reported in "Post Exposure". He claims it's effective.

-- Thomas Wollstein (thomas_wollstein@web.de), October 19, 2000.

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