Buffered with calcium carbonate 2-3% alkaline reserve, pH 9 +/-0.5,.Acid-free.
Un-Buffered, pH 6.5 - 7.2 No calcium carbonate -Acid-free.
Light weight 20-34g/per square meter 1.5 mil thicknesses Caliper 0.0012
Passes the PAT (Photographic Activity Test) ISO 14523 (formerly ANSI IT9.16). and TAPPI T444 silver tarnish test
Sulphur Content (Maximum) 0.0004
The Archival Methods Wide Archival Tissue is excellent for interleaving prints and drawings and protecting artifacts. Tissue is buffered for added protection. It is acid-and lignin-free and thin for easy folding, padding or crumpling without hard edges.