ACID FREE PAPER

Acid-free paper is paper that has a neutral or basic pH (7 or slightly greater). It addresses the problem of preserving documents for long periods. Paper made from wood-based pulp that has not had its lignin removed goes yellow and deteriorates over time. When exposed to light and/or heat, the molecules in the wood-pulp (or acidic) paper will break down even faster. It was only in the 1930s that the effects of wood-pulp paper became known, when William Barrow (a librarian) published a report about the deterioration of acidic paper in our libraries. For fear of the gradual disintegration of written materials, measures have been taken to improve the quality of paper.
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Le papier non acide est un papier qui possède un pH neutre ou basique (7 ou légèrement supérieur). Cette propriété permet une conservation des documents pour de longues périodes.
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Arkivpapper är ett, av Sveriges Provnings- och Forskningsinstitut (SP), godkänt åldringsbeständigt papper.
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(n.) = papel neutro, papel no ácido, papel sin acidez
Ex: Acid-free paper is now available at a price which competes with acid paper.

Def: Papel que ha sido tratado especialmente para que su grado de acidez, medido en valores pH, sea bajo pues ésta es una de las causas principales del deterioro del mismo
Ex: Acid-free paper is now available at a price which competes with acid paper.