Michigan State University
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Deacidification and Acidic Paper

Before the Civil War, paper was made from cotton and linen. These fibers made a very durable paper, but acquiring the materials and processing them was time consuming and costly. As the demand for paper increased, a new materials and paper-making techniques were required to meet the demand. Wood pulp was the new material and while it met the increased demand for paper, it came a host of problems.

When paper made from wood pulp reacts with heat, light and moisture, acids are formed. As these acids react with the paper, it becomes more yellow and less flexible, until it becomes brittle. Once brittle, there is nothing that can be done to save it. Preventive measures can help, such as keeping the paper from heat, light and humidity, and will considerably slow the formation of acids.

However, even under the best environmental circumstances, paper will release acidic compounds, so to minimize the damage, an alkaline buffer is placed within the fibers of the paper. This can be done without water by using a deacidification solution, such as BookKeepers, on the book. The solution can either be sprayed onto the pages or the book can be immersed in the alkaline solution as most vendors do. This option is chosen when there are media on the paper that will be disturbed by water or if the book does not need to be disbound.

The other option is using an alkaline solution, such as calcium hydroxide or magnesium bicarbonate, while washing the pages of a book. Aqueous deacidification can insure the most widespread and even distribution of alkaline compounds in the paper. Washing has the added benefit of rinsing accumulated acids out of the paper, before the alkaline solution is introduced.