IronMan wrote: InvstmntComcSupplies wrote: IronMan wrote:
IronMan wrote:It has always been the subject of some controversy as to whether or not microchamber paper offers any real archival benefit.
False, as an alkaline reserve, microchamber paper has proven archival benefits. There is no controversy about this with any conservation professional. Additionally there are benefits from the zeolites which act a molecular sieve to remove other pollutants unaffected by the alkaline buffering.
How about a link or two of testing labs, professional publications or some such - that don't sell the stuff - establishing actual tested benefits? Even the conservation professionals you speak of.
The library of Congress doesn't mention it.
The Library of Congress did the Mylar study which showed the need of an alkaline reserve in mylar.
The few scholarly type places that I've seen mention it primarily discuss it as something to absorb odors. And in further checking around I find one actual lab test where it is suggested that microchamber paper used in a sealed environment might not be all that effective:
A quote of the summary of results: Microchamber board should function best as a barrier between the object to be protected and the volatile molecule(s) to be trapped. This situation is more likely to occur in an open storage area where air quality is poor or in a space where air circulates and objects that off gas....
Microchamber paper as used in storage of comic books is not in an open storage area where air quality is poor. Nor does air circulate inside a sealed bag. http://cool.conservation-us.org/coolaic ... p23-14.pdf
I would like to see the entire study. I think you are misinterpreting the results. The point being that you want the microchamber as close to the item you are protecting as possible. The further away it is, the worse the performance. I don't think it gets any closer than between the pages.
From the same article:
Other results were suggestive of the possibility that the
Microchamber board could provide a protective effect for
newsprint over a much longer time period than that of the
experiment. The newsprint samples kept in the dark in the
presence of cellulose acetate, cellulose nitrate, or chipboard
were beginning to show a very slight trend of darkening in
the regular mat board passepartout, as compared to the
Microchamber board passepartout. Monitoring would
need to be continued for a much longer time period to
confirm that these differences were due to the different
From the same website http://cool.conservation-us.org/waac/wn/wn18/wn18-1/wn18-106.html
and this on microclimates from cool conservation http://www.cool.conservation-us.org/byauth/peters/peters1.html
and finally this
Library of Congress wrote: "At the moderate concentrations examined (2‐20 ppm acetic acid), the zeolite‐loaded rag boards adsorbed acetic acid vapor faster than the plain or buffered boards with the same fiber furnish. Zeolites and zeolite‐loaded housing materials can be effective pollution sorbents in library and archival environments, provided that their application is made with an understanding of their limitations. This pilot study of rag board with and without calcium carbonate and zeolite sorbents has demonstrated sorption effectiveness at real‐world, low concentrations of acetic acid in an unforced physical."
Full study here http://www.loc.gov/preservation/scientists/projects/NB%20Zeolite%20Report.pdf