Documentation photographic paper

This method of chromatogram preservation has lost a great deal of its importance with the increasing perfection of photographic methods, particularly since true-colored, instant, paper and slide positives have become available. Photography is the more rapid method of documentation if suitable photographic equipment is available. 

Why does the amount of acid in paper make such a difference Acids are corrosive chemicals. Corrosive chemicals can destroy material or living tissue on contact. Paper does not contain enough acid to burn skin, but over time the paper becomes stiff and brittle and eventually falls apart. As a result, precious personal memories or important historical documents that were written on acidic paper can be lost. Acid-containing paper can also transfer the acid to other objects in a process called acid migration. The acid can weaken or destroy the fibers in fabrics. It can also ruin photographs. Therefore, to preserve those irreplaceable memories, be sure to use paper that is acid-free. 

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