Library of Congress purchased the only existing Waldseemüller map four years ago. Created in 1507, the map is the first world map to dub America “ America .” When the map went on display in 2007, NIST needed a way to protect it while still making it accessible to the public. Their solution: laminated glass made with Saflex ® protective interlayer.
“We worked with the NIST team a few years ago to create the Charters of Freedom encasements for the Bill of Rights and the U.S. Constitution,” says Julie Schimmelpenningh, technical applications manager at Solutia Inc, manufacturer of Saflex protective interlayers. “The difference was that this encasement is significantly larger than the Charters of Freedom encasements – larger by more than six times. The glass needed to be pristine in edge work, alignment, haze and visual cleanliness. The overall size and quality requirements of the product coupled with the timing made it a challenge, but one that was met with enthusiasm. The large, durable piece of glass also required a re-engineered frame versus those used for the Charters of Freedom.”
To provide adequate protection, NIST designed a hermitically-sealed 116 inch by 73 inch encasement for the 12-sheet map. Using an anodized aluminum frame and laminated glass, the encasement was created to provide optimal accessibility while still protecting and securing the document.
The glass itself is made of low-iron glass sandwiching Saflex DM interlayer. This tough PVB interlayer protects the map in multiple ways. First, even if the glass is cracked, fragments will adhere to the interlayer, protecting the document from falling glass shards. Secondly, the interlayer, bonding between two pieces of glass under heat and pressure, is incredibly tough and nearly impossible to cut through from only one side. This is a tremendous security feature. Finally, Saflex interlayers block 99 percent of ultraviolet (UV) light up to 380 nm. This helps prevent fading and damage to the document.