Preservation

Comparison of Drying Methods

Bound volumes behaved much like unrestrained loose pages when dried.  The patented freeze-dry process produced results most like the control.  In general, if volumes are misshapen when packed for freeze-drying, they remain in that shape when dry.  The patented vacuum freeze-dry process is specifically designed to press volumes back into shape through a compression system in its drying cycle, thus reducing the need for rebinding; volumes fit back on the shelves as they once were. 

The patented process developers have also introduced a Rare Book Drying method in which a text-block is dried without desiccating its leather covers, diminishing the likelihood of broken hinges and need for subsequent repair.  This approach is, however, more than 4 times the cost of traditional vacuum freeze drying. ($250 per cubic foot)

Slide 32
Comparison of Drying Methods
Kaplan/Ludwig 2003

Not all books readily opened flat once dried.  Both vacuum-freeze-dried samples felt stiff and were resistant to opening flat. 

Slide 33
Comparison of Drying Methods
Kaplan/Ludwig 2003

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