Preservation

Comparison of Drying Methods

Non-water soluble coatings, such as cellulose nitrate, found on mid to late 20th century architectural linens, bubbled in areas where water was trapped.  Damage was apparent in all test samples but seemed most severe in vacuum freeze-drying processes. 

Slide 42
Comparison of Drying Methods
Kaplan/Ludwig 2003

Groupings of polyester-sleeved items were placed within sample boxes to see if they could be successfully vacuum-freeze dried.  Would the vacuum process sublimate  water out of openings in the sleeves?  Would water be effectively removed from encapsulations where corners were clipped?  Would water be removed from an ultrasonic or heat welded item?

Slide 43
Comparison of Drying Methods
Kaplan/Ludwig 2003

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