Fact box

The deterioration of books is influenced by many factors, such as sunlight, dust, air and ultraviolet rays. Maintaining stable temperature and humidity levels can help slow the aging process. Deacidification of the paper is also an effective way of maintaining old books.

Many libraries have started digitizing the content of the books onto microfilm and have also built online databases.

It takes about 30 to 40 procedures to restore an ancient book. Major steps include removing the threads and separating the pages, using special paper and paste to repair damaged areas, spraying water and flattening the pages, drying them, flattening them with a pressing machine and rebinding. The principle is to restore each book to its original state and maintain its information to the greatest extent.

Books may be damaged by natural aging, by insects or vermin, or by burning or soaking in water.

If a book cannot be opened after being soaked in water, the restorers have to steam it dry.

A professional restorer needs to have a wide range of knowledge, including history, ancient languages, culture, chemistry and archaeology.