Acid and lignin free purified wood pulp with 2-3% calcium carbonate buffering. This is the requirement of ISO IT18902 for photographic and ink jet prints except cyanotypes and dye-transfer images. Paper passes the PAT test ISO IT 18916 The Photographic Activity Test. Smooth surface on both sides. @@ High alpha cellulose pulp from purified wood fiber @@ Buffered with calcium carbonate 2-3% alkaline reserve pH 9 +/-0.5 acid-free @@ Passes the PAT Photographic Activity Test ISO IT 18916 @@ Sulfur content is less than 0.0008% reducible sulfur @@ Lignin content is tested by TAPPI 236 cm-85 and has a Kappa number of less than five @@ Paper will not degrade and cause harm to artwork or documents Application This paper is specifically design as an interleaving paper for artwork and documents. The light weight paper has the thinness of a tissue and the stiffness of paper making it easy to handle and use. The paper had a weight of 45gsm providing a slight transparency which allows for identification of an image without removing the interleaving sheet. It is available in cut sheet sizes as well as rolls sized for contemporary ink jet papers.