Accelerated aging of deacidified and untreated book paper in 1967 compared with 52 years of natural aging
Tali H. Horst, and others
Restorer. International Journal for the Preservation of Library and Archival Material, ISSN 1865-8431, Vol. 41, n. 3, 2020, p. 131-152
Three copies of a book, two of them deacidified with two different methods in 1967 and then subjected to accelerated aging, were put to the test again after 52 years of natural aging. Corresponding copies of the book Cooking Greek, printed in the Czech Republic on acid paper were evaluated. A non-aqueous treatment of two specimens with magnesium methoxide dissolved in a chlorofluorocarbon solvent decreased the crumbling tendency in 1967, which was confirmed by accelerated aging results followed by folding resistance tests. New tests carried out in 2019 on the same books after 52 years of storage at room temperature showed that the deacidification treatments have had complementary beneficial results compared to the untreated book: a higher gloss; greater resistance to bending; a greater tensile break length in the transverse direction; a substantial reserve alkaline content; an alkaline PH surface in the range 7.1-7.4; and a higher molecular mass of cellulose. It can be noted that some of the results of the folding resistance tests conform to those of the unaged samples evaluated in 1967. Scanner images have shown no differences between treated and untreated books.
Translation of the abstract of the publication itself