A STUDY ON SPINNING LIMITS AND YARN PROPERTIES WITH PROGRESSIVE CHANGE IN YARN COUNT IN FRICTION SPINNING
The spinning limit for three different fibres (cotton, viscose rayon and polyester) on a Dref-3 friction spinning machine has been investigated. The change in yarn properties with progressive change in count has also been reported. The count range has been seen to be dependent on fibre type. As one progresses from very coarse to fine counts, the yarn tensile property remain fairly unaltered for cotton, but changes for polyester and viscose yarns.
STUDIES ON WOOLLEN THREADS FROM HISTORICAL TAPESTRIES
Fourier transform (FTIR) attenuated total reflectance (ATR) and second derivative spectroscopy has been used for the first time to evaluate the state of degradation in historical woollen threads from the collections of Flemish tapestries (15th-17th centuries) in the Royal Palace, Madrid, Hampton Court Palace, and museums in Brussels. The work was performed as part of the EC-funded project "Monitoring of Damage in Historic Tapestries", also known as the MODHT project . The overall aim was to develop procedures for recognising tapestries at risk and provide analysis for informing collection care. Prior to the testing of the historical threads, model tapestries were prepared according to traditional techniques of weaving and dyeing. They were then subjected to accelerated light ageing. This paper reports on the part of the MODHT project in which ATR-FTIR was used. It was selected since it is a non-destructive method, and also because it has previously been used to study the oxidation products of cystine in wool and to provide a semi-quantitative assessment of change . Evaluation was conducted on the model tapestries, and the cysteic acid peak was selected as the marker for change, as it showed a systematic change with light ageing. The same marker was used to assess the change in historical threads.
PREDICTION OF FABRIC COMPRESSIVE PROPERTIES USING ARTIFICIAL NEURAL NETWORKS
Data analysis relating to a fabric's compression properties can only be carried out when the limits of compression are known. The study of the compressibility of woven fabrics was initiated with Peirce, Kemp & Hamilton's approach to circular yarns and flattened yarns of a fabric under pressure. The fit of the pressure-thickness relationship is being improved using the exponential interpolation & extrapolation methods, as well as iterative methods such as the Marquardt algorithm for fitting the curves. Although there is a recent trend towards the automation of studying the structure-property relationship of textile fabrics, an objective and efficient method for predicting properties with a rapid prototype that outputs to sophisticated instruments such as the KES-FB3 is essential. This characterisation of data for fabric materials will help maintain companies' commercial experience and expertise. This established predicting model can provide guidance to fabric manufacturers, fashion designers and ?[makers-up] in fabric design, fabric selection and the proper use of fabrics. This approach will make online fabric sourcing more realistic. Fabric sourcing experts are now visiting supplier's websites for tracking fabrics. Overall, this approach provides an opportunity to generate a dynamic database of fabric properties, and hence may result in the development of new fabrics or the updating of existing fabrics to keep pace with fashion.
COMFORT AND HANDLE BEHAVIOUR OF LINEN-BLENDED FABRICS
Few can dispute the tremendous values of linen, which is one of nature's greatest treasures. Linen is a longer-staple category, and as such the fibre is spun on a long-fibre spinning system. Due to the coarseness and stiffness of the fibre, linen fabrics are subjected to a strong bleaching action to reduce the stiffness of the fabric. Linen is also blended with other compatible natural and manmade fibres to achieve various structural and functional properties, and also to reduce costs. Fabrics produced from 100% linen and their blends with cotton and viscose have been studied for handle and comfort properties. Linen fabrics produce excellent aesthetic and drape properties. Linen fabrics are found to be tougher than cotton and other blends. However, linen offers the highest tensile resilience and the lowest friction coefficient under low stress-loading conditions. Linen fabric produces superior primary hand with respect to Fukurami and Shari. The total hand value (THV) of processed linen fabric is higher than that of cotton fabric as a summer wear. The blending of viscose and cotton improves the hand value of linen fabric.
INFLUENCE OF CHEMICAL TREATMENTS ON INTER-FIBRE COHESION IN YARNS
This paper discusses the influence of various chemical treatments on inter-fibre cohesion in yarns. Treatments given include mercerisation in slack and taut conditions, cytan, acetylation, benzyolation and enzymatic treatments. The studies reveal that the inter-fibre cohesion in yarns improve with these treatments.
UV PROTECTION TEXTILE MATERIALS
Ultraviolet rays constitute a very low fraction in the solar spectrum but influence all living organisms and their metabolisms. These radiations can cause a range of effects from simple tanning to highly malignant skin cancers, if unprotected. Sunscreen lotions, clothing and shade structures provide protection from the deleterious effects of ultraviolet radiations. Alterations in the construction parameters of fabrics with appropriate light absorbers and suitable finishing methods can be employed as UV protection fabrics. This paper deals with the deleterious effects of UV rays and protection against them through textile materials.
POROSITY DETERMINATION OF JERSEY STRUCTURE
In our paper, we attempt to investigate methods of determining jersey porosity which is this fabric's principal physical characteristic. In fact, end use, liquid absorbency, thermal comfort and resistance are closely related to pore size and distribution. So it is important to study porosity, in order to classify and determine the right use of jersey knitted structure. Many methods are used to estimate porosity, but most concern air permeability, image processing and geometry modelling. The first mentioned is used for the stretched structure, the second is valid for fabrics with high porosity levels, and the last mentioned is used to confirm any structure's conformation.
The aims of this study are twofold; firstly, to recognise the most suitable and easiest method of estimating the fabric's porosity, and secondly to study the influence on porosity of various knitting parameters of jersey structure such as yarn number and count, fabric thickness, loop length, and stitch density.
LABORATORY AGEING TEST DEVICE FOR PRESS-FELT CLOTHES OF PAPER MACHINE
The main part of the de-watering process in a paper machine (PM) is carried out by means of mechanical pressing, which considerably influences the paper quality and energy efficiency of the paper machine. This paper discusses a method for controlled press-felt mechanical degradation. For our research, a special test device was designed and developed to simulate press-felt ageing in the pressing section of paper machines. All the described methods and tests were carried out in the Institute of Fibre Materials Science at Tampere University of Technology.