C

 

Calcium carbonate

An alkaline chemical used as a buffer in paper and boards.

Cellulose

Chemically, a complex carbohydrate. Cellulose is the chief constituent of the cell walls of plants, and consequently the chief constituent of many fibrous plant products such as paper and board, and cotton, linen and rayon cloth. Traditional Western plants providing cellulose for paper were cotton and linen ('rag' paper). Wood is the major source of papermaking fibres today. The quality of wood pulp papers can vary from very high to very low, depending both on the methods of extraction of the cellulose fibres and manufacturing methods.

Chemical stability

Not easily decomposed or otherwise modified chemically. This is a desirable characteristic for materials used in preservation, since it suggests an ability to resist chemical degradation, such as paper embrittlement, over time and/or exposure to varying conditions during use or storage. Sometimes described as chemically inert.

Coated paper

Paper with a surface coating (adhesives, clay or other pigments etc) that is added to improve its finish in terms of printability, smoothness or opacity. Coated papers usually have a glossy appearance and are sometimes called 'art papers’. Older clay coated papers have a tendency to block when they are exposed to high relative humidity or become wet.

Conservation

The use of procedures to preserve and repair the physical structure of an item. All processes ideally should be reversible.

Conservator

A person professionally responsible for the physical preservation of collection items in order to retain and maintain their evidential or informational content.