Volume 8, Number 2, May 1986, p. 8
Wolfgang Waechter spoke at the October meeting of the Washington [DC] Conservation Group about two methods used at the German Depository Library in Leipzig, where he is Chief of the Restoration Department. His talk was summarized by Jesse Munn in the Guild's January newsletter (v.10 #1).
In 1979 his library started using a mechanized facility designed by Mr. Waechter for treatment of large numbers of pages, each of which needs exactly the same treatment. It can perform a large number of wet treatments in one operation--washing, rinsing, buffering, enzyme treatment, bleaching, and sizing. It monitors pH and controls the temperature of solutions.
The sheets are either packed or rolled up with separating sheets of porous plastic and placed in a transport system that carries the rolls or bundles from one sink to another, six in all, each with its own controls. Up to 400 sheets can be treated simultaneously without being handled in the wet state.
The paper splitting process is not a recent development: it was first described in the late nineteenth century. It is not mechanized either, though it is economical. It is ideal for damaged or embrittled paper, including paper made into lacework by iron gall ink. First support sheets are adhered to the original, using a warm-water-soluble adhesive (gelatin). They are pulled apart, splitting the original, and a third sheet of support tissue is inserted between the halves and adhered with a cold-water-soluble adhesive (methyl cellulose). The outer support sheets are soaked off in a warm water bath. Mr. Waechter expected this process to be mechanized sometime during 1986.