Towards a Longer Lasting Leather
Details of a project aiming to develop of a range of bookbinding leathers which combines the chemical stability to resist the effect of acidic atmospheric pollutants with the complex physical and organoleptic properties required by bookbinders and conservators.
R S Thomson, S Mehmet et al.
The continuing deterioration of leather bindings is a major concern for all libraries, archives and museums, situated in heavily polluted urban areas. Despite all the research that has been carried out, little of the leather used today carries any guarantee of long term durability. Such a situation may lead some National Libraries to think there is no future in the use of leather for bookbindings.
Research carried out in the 1980's by the then British Leather Manufacturer's Research association demonstrated that treating vegetable tanned leathers with aluminium salts increased their resistance to rotting by acidic atmospheric pollutants. This work lead to the establishment of British Standard No. 7451/1991 for archival quality binding leather.
The first commercially produced semi-aluminium binding leathers tended to be too stretchy and insufficiently wettable for ready acceptance by binders. Other problems included the inability to carry out hot tool lettering. Clearly a further approach was required to specifically identify the acceptable physical handling qualities required by binders.
Project details
The project:
Contract No. BRST-CT918-5535. The Development of Archival Quality Leather. Part funded under the BRITE-EURAM III-CRAFT Programme.
Co-ordinator:
Dr I A Loannidis, ELKEDE, Design & Technology Centre SA, 12th Kilometer Ethnikis Othou, Athinon-Lamias, Moraitini Str. Tel: +31-1-2855580, Fax: +31-1-284671; e-mail: me-med@ath.forthenet.gr.
The partners:
Tanners, craft and industrial bookbinders, libraries, museums, research and educational institutions from Germany, Greece, Italy and the United Kingdom. Go to list of partners.
The aim:
To develop a range of bookbinding leathers which combines the chemical stability to resist the effect of acidic atmospheric pollutants with the complex physical and organoleptic properties required by bookbinders and conservators.
Bookbinders at work testing Leather
Methodology:
1. To assess the current situation by:
- Examining a representative sample (72) of leathers used for bookbinding throughout Europe for their physical, chemical, organoleptic and ageing properties.
- Re-evaluating the artificial ageing regime developed during European Community funded STEP and ENVIRONMENT leather projects.
2. To develop a series of objective physical tests which correlate with the subjective organoleptic assessments carried out by skilled bookbinders.
3. To produce leathers on experimental, development and, finally, semi bulk scale using:
- Semi-metal processes
- Novel synthetic organic tanning methods
4. To examine these leathers for their suitability for bookbinding purposes
Scientific analysis and artificial ageing
Results so far:
1. Of the 72 commercial samples examined, the only products found to combine the require working characteristics with resistance to atmospheric pollution were:
- Allum tawed skins
- Parchment and vellum
- Undressed Native tanned Nigerian goatskins and two of the vegetable leathers tanned leathers retanned with aluminium
2. The artificial ageing regime developed during the STEP and ENVIRONMENT programmes is not valid as it does not predict the known long lasting properties of parchment, chrome tanned leathers and alum tawed skins.
3. A draft protocol has been developed to define the properties required of a bookbinding leather using standardised physical tests.
4. One range of leathers is being produced on a semi bulk industrial scale that combines all the required properties. This is being sampled to customers outside the consortium for a full commercial evaluation.
Graphs
Enlarge
