Textile Chemistry

Textiles and their products are susceptible to a variety of stains due to varied use and environment. Primary reason for the vulnerability of textiles is their organic origin, which renders them fit as food for microorganisms. The problem of pest infestation multiplies in case of museum textiles as most part of it is kept in storage for long periods of time. Even mild pest activity on surface of fabrics can result in tough stains originating from pest saliva, excretion and by-products of fiber breakdown. Termed as 'second-skin' by scholars, textiles evidently witness every single activity that becomes part of our life. Thus, in addition to the common stains like food, cosmetics etc, not so common stains like blood also find place on these organic surfaces. Most of the decorative textiles are either made in decorative weaves or a combination of base fabric with embellishments which many a times happen to be metal in various forms. These in turn give way to the persistent problem of fabric staining and damage due to rust. This research paper would primarily focus on the removal of three stains, i.e., rust, mould and blood and comparison of procedures for stain removal by traditional indigenous techniques, contemporary laboratory procedures and enzymes

Cleaning ensures sanitization and thus safety of the artefact itself and others stored/displayed in its vicinity. At the same time, the process invariably alters the character of textile to a certain extent. Cleaning ensures removal/deactivation of soil and harmful organic matter from the artefact. However, small amount of surface molecules from the textile might be eroded in the process as well. This leads to weakening of the textile and might cause alteration in colour spectrum/ depth etc. Controlled cleaning techniques in conservation laboratories focus on minimizing this damage. However, not much scientific data is available on efficacy of present cleaning techniques employed in conservation laboratories. Presently aqueous cleaning and solvent cleaning are primary modes utilised as next step to dry tools. Additionally novel cleaning technologies like enzyme wash and ultrasonic wash provide soil specific methodology that would reduce the threat to base fabric. Present paper is a systematic analysis of these cleaning techniques and their impact on aged museum fabrics, i.e., cotton, wool and silk. Change in tensile strength parameters, whiteness index and yellowness index have been used as indicators to test efficacy of different cleaning techniques on aged museum textiles. Numerical data generated by laboratory experiments clearly indicates that there is no standard cleaning treatment available for the three natural fibres. Each fibre has exhibited suitability to different cleaning treatment, while balancing between restored whiteness and minimizing strength loss.

Ageing is a complex process where a material undergoes changes at both, molecular and physical level. These changes are often irreversible and further impact the use and wear properties of the product. Also it should be noted that the changes in performance characteristics are mostly negative in the case of ageing. Another fact about ageing is that it is inevitable. The process cannot be arrested, it can only be delayed by certain mechanisms, in order to extend the usable lifetime of the product. Thus ageing of material becomes a matter of prime concern for curators and conservators. Essentially, the process of ageing contains two factors, 1. Shortening of molecular chains 2. Changes in the physical characteristics of a product Ageing is probably one of the most complex problems in conservation science, primarily because of its varied nature. Different materials age at different pace and the process itself is affected by different factors. As Robert Feller (1994) said, "The wide range of stability in materials is one of the chief reasons why it is impractical to specify a standard accelerated-aging test that can effectively evaluate both highly fugitive and highly stable materials"(1). Conservation scientists need to continuously predict further behaviour of the artefacts in their collection, in order to avoid damage. Therefore, in order to understand the useful lifetime of a product, it is imperative to understand its process of ageing. This can be best done by observing the object and measuring its parameters through its lifetime, which would be an extremely time intensive process and thus not compatible for most research and evaluation. This is where simulation comes into picture. Whatever we cannot create, we simulate! Thus accelerated ageing is the best suited tool which curators, conservators and scientists world over use to study and understand the reaction of a product to various circumstances it is expected to encounter in its lifetime. The free dictionary defines accelerated ageing as "hastening the deterioration of a product by a laboratory procedure in order to determine long-range storage and use characteristics". As per Intota (-expert consulting services company) it can be defined as "aging of a product or material that has been hastened by a laboratory procedure, such as exposure to intensified heat or pressure, usually in order to determine long-range storage and use characteristics:".