Volume 13, Number 1
Feb 1989

Mass Aqueous Deacidification

On request, Wilfried Feindt of the Niedersächsisches Staatsarchiv in West Germany has furnished the following information. His letter actually cane last August, so there has probably been significant progress on the project since then. His text has been minimally edited for clarity.

There is current research in two fields of paper conservation in our country. Both are financed by the federal administration (Bundesministerium für Forschung und Technologie). The project of the Deutsche Bibliothek, Frankfurt/Main, deals with deacidification/buffering of bound volumes. The treatments under evaluation are DEZ, the Smith process at Ottawa and the French one at Sablé.

The second project was initiated by us. Am institution at Munich (Papiertechnische Stiftung) is going to construct a machine for the treatment of single sheets of paper, as found mainly in archives. Two conservation treatments have been considered: the swelling process with sodium hydroxide and the well-known aqueous treatment with alkaline earth salts. Because of environmental problems with waste water from the machine, we just decided to build the one with calcium/magnesium salts first.

Several steps are performed within the proposed machine: the papers are numbered automatically at the entry point, transported through a fixing bath to prevent colors from bleeding, dried, bathed in a concentrated solution of magnesium bicarbonate, dried again, sized with carboxymethyl cellulose, dried for a third time, and flattened as a last step....

It will take about two years to get the machine running in our workshop. The intended production is 300 sheets 80x60 cm per hour, or 600 sheets of A3 per hour. The leaves are fed into the machine by one person.