Acid size

Description

Any paper size which increases the acidity of the paper pulp. Acid sized paper typically has a pH of 4.5 to 6.0. One type of acid size is a rosin-alum mixture. Starting in the 1820s, Aluminum sulfate, or papermakers alum, was added to rosin size causing it to flocculate to the cellulosic fibers in the pulp solution. However, residual alum in the paper produces an acidic environment that accelerates the degradation of paper.

Synonyms and Related Terms

white size

Authority

• Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982

• Roy Perkinson, contributed information, 1998