Preservation

Comparison of Drying Methods

Vacuum Freeze-Drying: Advantages

  • Vacuum freeze-drying is the drying method of choice for large quantities of wet materials.
  • It results in the least amount of distortion, precluding the need to re-house or relabel most materials.
  • Freezing immobilizes water to minimize corrosion from metal fasteners and on-going running or bleeding from soluble media.
  • Coated papers do not stick to one another when vacuum freeze-dried.
  • Even items enclosed in plastic need not be removed from  original housings or enclosures, so there is less chance for loss of original order

Slide 56
Comparison of Drying Methods
Kaplan/Ludwig 2003

Vacuum Freeze-Drying: Disadvantages

  • While advantages generally outweigh disadvantages, vacuum freeze-drying also has downsides.
  •  Access to materials while frozen or during drying is not possible. Your materials may be placed with records belonging to others in the drying chamber, and ownership confusion may result. 
  • While the cost for freeze-drying appears comparable to other processes,  materials must be kept frozen during transport and these associated costs may make freeze-drying small quantities of materials expensive. 
  • Increased delamination in cellulose nitrate coated architectural drawings was noted. 


Slide 57
Comparison of Drying Methods
Kaplan/Ludwig 2003

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