Chemical Processes in the Bleaching of Paper in Library and Archival Collections

Describes in detail the chemical reactions that happen during bleaching processes in the restoration workshop. The formation and destruction of chromophores in cellulose, hemicellulose, and lignin are discussed. Their destruction or removal is difficult, bearing in mind the artistic and historical values of artifacts undergoing conservation, because all chemical bleaching methods used in the conservation of both historical and modern paper always cause some damage. This is why, before applying any bleaching method, one should know the chemistry of the bleach and try all other alternatives suited for the removal of stains, impurities, or the darkening of paper, by surface cleaning with soft rubber or a brush, washing and cleaning by means of surface-active compounds, organic solvents, or enzymes. -- ICCROM