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1. RE: Non-Aqueous Deacidification Prior to Encapsulation? ------------------------------------------------------------------------------------------------------------ 1.From: Valeria Orlandini Posted: Saturday November 22, 2025 12:24 PM Subject: RE: Non-Aqueous Deacidification Prior to Encapsulation? Message: Hi Adrienne, Thanks for posting this interesting inquiry about the use of non-aqueous deacidification and encapsulation (re-housing). I find that it is important to discuss this matter further among conservators and conservation scientists. Note: Deacidification, is a less precise term, which includes the concepts of neutralization, alkalization, and sometimes the removal of soluble acidity by washing (with full immersion). Neutralization: Application of an alkaline agent which reacts with acids in paper to form a salt. Alkalization: Application of an alkaline agent which reacts with acids in the paper and leaves in paper an alkaline reserve capable of reacting with acids in the future. (Because it enables paper to resist changes in pH, an alkaline reserve is sometimes called a buffer, and the treatment "buffering".) BPG Alkalization and Neutralization - MediaWiki <https://www.conservation-wiki.com/wiki/BPG_Alkalization_and_Neutralization> I'd like to know what type of paper-based materials you are planning to treat with a non-aqueous deacidification/ alkalization? Which non-aqueous deacidification method or reagents are you using in your lab? I agree with Cher's comment: "It's important to remember that deacidification spray is preventative, not restorative, and it only provides a superficial level of treatment." It's an intervention where you don't know what the pH of the paper is present before and after treatments to allow alkalinization and a deposit of an "alkaline reserve." Without a full immersion of the paper -- after an aqueous bathing and stabilization with an alkaline reserve deposit one cannot measure both "quantitative and qualitative" analyses and pHs. When a non-aqueous deacidification reagent is applied, there is no way to carry out titration as with aqueous deacidification, for example with solutions of Calcium bicarbonate and/or Magnesium bicarbonate. The efficacy of strengthening and deacidification process(es) in increasing the permanence and durability of paper are in question. The permanence increase following treatment is found to be strongly dependent upon properties of the untreated paper, pH, its strength at the time of treatment, the particular mode of strengthening employed, and the process parameters specific to each treatment process. The Effects of Strengthening and Deacidification on Paper Permanence: Part I--some Fundamental Considerations by Donald K. Sebera, Chemist at the Library of Congress (1990) The Effects of Strengthening and Deacidification on Paper Permanence: Part I -- Some Fundamental Considerations <https://cool.culturalheritage.org/coolaic/sg/bpg/annual/v09/bpga09-09.pdf> In 2002, I carried out an experiment in Canada to assess various aqueous treatments to stabilize ink-corroded materials. The results and findings of this research addressed and concluded that both solutions of deacidification with Ca bicarbonate and Mg bicarbonate used from the Library and Archives Canada in Gatineau, Quebec and in conjunction with the Canadian Conservation Institute (CCI) in Ottawa, Ontario - didn't leave an alkaline reserve deposit after washing. Those samples that were treated with alkalinization reached pHs around 7, 7.5 and less with measurements carried out in 2002 as well as then recorded with a surface electrode in December 2004 and with cold water extractions in June 2006. Results can be found in the article: Effect of Aqueous Treatments on Nineteenth-Century Iron-Gall-Ink Documents: Calcium Phytate Treatment-Optimization of Existing Protocols by Valeria Orlandini, The Book and Paper Group Annual 28 (2009) 137-146. bpga28-24.pdf <https://cool.culturalheritage.org/coolaic/sg/bpg/annual/v28/bpga28-24.pdf> Hope to hear your comments and follow up with the discussions. <https://cool.culturalheritage.org/coolaic/sg/bpg/annual/v28/bpga28-24.pdf> Kind regards, Valeria P.S. Further inquiries following Sebera's article. What is the minimum amount of strengthening which is useful and economically justifiable? Is it adequate to give all papers an equal increase in strength or should the weakest papers be strengthened most? If strengthening is a one-time event with no change in the rate of paper deterioration, how much is the permanence of the paper extended? What, if any, are the relationships among paper strengthening, paper deacidification and paper permanence? Hope the article by John Baty et al entitled DEACIDIFICATION FOR THE CONSERVATION AND PRESERVATION OF PAPER-BASED WORKS: A REVIEW will be of interest to you. <[email protected]> ------------------------------ Valeria Orlandini Conservator of Works on Paper and Photographic Materials Chevy Chase MD (301) 657-2682 ------------------------------ ------------------------------------------- Original Message: Sent: 11-18-2025 11:34 From: Adrienne Bell Subject: Non-Aqueous Deacidification Prior to Encapsulation? The Department of Preservation and Conservation Services, University Libraries, at the University of North Carolina at Chapel Hill is interested in whether institutions are non-aqueously deacidifying materials prior to encapsulation or not. Any research, protocols, or thoughts supporting the decision would be appreciated. Responses can be sent directly to [email protected] <[email protected]>; if there is any interest from other institutions, responses can be compiled for anonymity and shared. ------------------------------ Adrienne Bell Senior Conservator UNC Chapel Hill Libraries Chapel Hill NC ------------------------------ You are subscribed to "Global Conservation Forum (ConsDistList)" as [email protected]. To change your subscriptions, go to http://community.culturalheritage.org/preferences?section=Subscriptions. To unsubscribe from this community discussion, go to https://community.culturalheritage.org/HigherLogic/eGroups/Unsubscribe.aspx?UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e&GroupKey=757a8f16-505f-4323-8e74-e376757aa9f7.
