A measured value used to determine the condition and stability of cellulose. The copper number is determined as the amount of copper reduced from the cupric to the cuprous state by 100 grams of cellulose pulp. A high copper number indicates that the cellulose is not pure and may have been degraded by bleaching. A low copper number indicates that the cellulose is not degraded. This test does not account for the presence of lignin.
Sources Checked for Data in Record
- The Dictionary of Paper, American Paper Institute, New York, Fourth Edition, 1980
- Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982