Acid-free paper Acid-free paper Acid-free paper is paper that if infused in water yields a neutral or basic pH (7 or slightly greater). It can be made from any cellulose fiber as long as the active acid pulp is eliminated during processing. It is also lignin- and sulfur-free. Acid-free paper addresses the problem of preserving documents and artwork for long periods. Paper made from wood-based pulp that has not had its lignin removed turns yellow, becomes brittle, and deteriorates over time. When exposed to light and/or heat, the molecules in the acidic paper will break down even faster. Acidic wood-pulp paper became
Bohemic acid under neutral or slightly basic pH conditions, and the fats and oils are removed by washing with petroleum ether. Chromatographical separation, in addition to the antibiotics pyrromycin and cinerubin A and B, reveals several individual components of bohemic acid, including alcindoromycin, bohemamine, collinemycin, marcellomycin, mimimycin, musettamycin, rudolphomycin and schaunardimycin. Their names originate from the characters Alcindoro, Colline, Marcello, Mimì, Musetta, Rodolfo (Rudolph) and Schaunard of the Puccini opera "La Bohème", and the acid itself and the bohemamine component carry the name of the opera. The suffix "-mycin" is conventionally added to indicate antibiotics derived from actinobacteria or fungi. The individual