BS 7451:1991

Committees responsible
Foreword
Specification
1. Scope
2. Definitions
3. Sampling
4. Conditioning
5. Chemical and physical properties
6. Marking
Appendices
A. Background information to the standard
B. Method of test for tarnishing
C. Calculation of surface shrinkage in boiling water
Tables
1. Chemical properties
2. Physical properties
Figures
1. Assembly as used for test samples
2. Assembly as used for control samples

Specifies the chemical and physical properties of bookbinding leather where the overall priority is long term stability when exposed to atmospheric pollutants.

This British Standard specifies requirements for leather to be used in archival bookbinding, for which purpose the following leathers are suitable:

1. semi-alum leather, as defined in BS 2780 (term 234);
2. chrome re-tan leather, in which the leather has been first chrome tanned throughout its thickness, then tanned with vegetable tanning agents, as defined in BS 2780 (term 52) and is then further treated with basic aluminium salts.

Leathers tanned solely with vegetable tannins, or chrome re-tan leather in which the chrome tanned leather has been further tanned solely with vegetable tanning agents, are not suitable and are thereby excluded. In addition, although alum tawed bindings have been proved to have long term durability, alum tawing cannot be regarded as a true tannage and therefore such leather is not included in this specification.

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.