Historically, most of society’s writings and visual images have been recorded on paper.
However, paper is an organic material and is subject to deterioration caused by chemical, physical and biological agents. While documents on paper several hundreds of years old have endured, most paper manufactured in the last two hundred years has a limited storage life due primarily to acidity induced as part of paper manufacturing processes used during that time period. Exposure to acidic air pollutants also contributes to paper degradation.