Papers by Keyword: Wool

Abstract: It is common knowledge that natural dyes are fit for textile dyeing since ancient times. Basically, natural dyes are elements derived from natural resources, and classified as plant, animal, mineral, and microbial dyes based upon their source of origin. Natural dyeing is a very important part of the old Portuguese tradition which is, currently, regaining awareness due to sustainability and health issues that has arisen from the massive application of synthetic dyes in textile coloration. In this study we sought to optimize the extraction of Sorghum vulgare (curumanine and apigeninidin) through the use of a design of experiments (DOE) methodology and to develop an analytical method by high performance liquid chromatography-diode array detector (HPLC-DAD) for their quantification. Dyes extracted and isolated were then used to dye 100% wool jersey knits by way of the exhaustion process. The color strength and fastness properties of the dyed samples against washing, and rubbing were evaluated. Our findings proved that meta-mordanted samples dyed at 80°C for 4h obtained the best strength and color fastness results.

Abstract: New technologies are using natural fibres in composites materials in the industry. It is still often natural fibres in modern buildings, chemists, airports, sport and automotive. Using for construction pieces and their better properties than steel or traditional materials. New forward science and technic are recycled or decrease waste. The problem for central Europe is a waste of agricultural, invention relates to an epoxy resin filled with an organo-inorganic filler of natural origin, production especially plants and sheep wool as well as other usable wastes such as old textiles. New applications are in new construction types and industries finding cheaper materials. There is available modern technology for injection moulding granulate polypropylene with filler from sheep wool and plant fibres. For example, to make furniture or building cladding. This could reduce waste production, pollution of nature and emissions in the production of these products from new raw materials. The work presents the possibilities of using new polymer-based materials contain sheep wool as filler. The paper deals with the evaluation of the mechanical properties of the effect of the addition of sheep wool in a concentration of 3% to selected types of thermosetting matrices. In the experiments, the modulus of elasticity, tensile strength, ductility and deformation work were built on the sample set. The results are statistically processed and document the possibilities of adjusting the mechanical properties of composites with sheep wool.

Abstract: In the last decades the studies on thermoplastic composites reinforced with natural fibres have been mostly focused on vegetable lignocellulosic or cellulosic fibres. These materials provide eco-sustainable solutions for a large range of applications and have been actually adopted by multiple industries. The interest on fibres of animal origin is more recent and research on composites reinforced with these fibres predominantly composed of keratin, such as wool, feathers or silk, is increasing in virtue of some advantageous properties that may overcome some of the intrinsic limitations from vegetable fibres. The combined use of vegetable and animal fibres in composites appropriate for melt blending processing is at early stages of research. After chemical treatments, the fibres of animal origin have been mostly applied as binders between vegetable fibres and polymers, not as main constituents of these composites. The use of both types of fibres simultaneously in composites of thermoplastic matrices is the subject of the present study wherein the fibres of animal origin (wool) are different kinds of residues from a textile industry and the fibres of vegetable origin (wood) are residues from carpentry activities. The chemical composition, the macro and microstructure of the fibres is analyzed, as well as that of composites that combine non-biodegradable and biodegradable polymers with diverse ratios of fibres in different conditions (wool as cards, yarns and felt cloths; wood as sawdust). The addition of coupling agents to enhance the compatibility between wool, wood and different polymers is also analysed.

Abstract: The hair follicles of most mammals are of two types, primary and secondary. Primary follicles develop earlier and have a prominent arrectorpili muscle. Secondary follicles have less prominent muscles and are often clumped, sharing a common opening from which fibres emerge. It is not entirely clear what types of follicles occur in human scalps. Partly this is because human hairs have a uniform appearance, unlike many mammals in which robust primary hairs differ markedly from narrow secondary fibres. Some sheep breeds are an exception because like humans, wool fibres have a similar macro-scale appearance irrespective of follicle type. How deep does this similarity go Using electron microscopy, we examined wool primary fibres from different breeds and contrasted them to secondary fibres. For fibres of similar diameter, there was no significant difference in the ultrastructure or proportion and distribution of cortex cell types in primary and secondary fibres. We conclude that fibre diameter is the most important fibre parameter with respect to structural differences between fibres, not whether the fibres originate from primary or secondary follicles.

Abstract: The effect of varying gelatin concentration and temperature on the levelness of wool dyed with 2.0% o.m.f. indigo for various time periods was investigated. The degree of levelness was measured in terms of (RUI)_C values. (RUI)_C stands for corrected relative unlevelness index as reported in the work of Chong et al. [1]. The colour fastness to washing of the indigo-dyed wool using gelatin as a buffer was also determined.Gelatin, used as a buffer, potentially maintained the dyebath pH at a constant value of 10 which consequently reduced the colour variations between dyeings. The levelness of dyeing and depth of shade was found to be unaffected by varying concentrations of gelatin. While longer dyeing times resulted in higher degree of levelness and enhanced shade depths, higher dyeing temperatures did not favour the dyeing of wool with indigo, in that lower shade depths and reduced levelness were achieved. Dyeings of excellent wash fastness and dry and wet rubbing fastness were obtained.

Abstract: Cashmere is one of the finest and softest animal fibers used by textile industry. False declaration is quite common due to its scarcity and high economic value. We have developed an objective method for quantifying cashmere and wool mixture based on DNA technology. Mitochondrial DNA, a species-specific genetic material exists in each cell, presenting a relatively strong capacity to resist physical and chemical treatments, seems to be an ideal target for species identification. As goat and sheep belong to a different genus, a real-time PCR based analysis method for quantifying cashmere and wool mixture was developed. Cashmere collected from different countries and regions were employed to prove its effectiveness. Dyed samples provided by CCMI round trial showed that it is a reliable and objective method. Various cashmere products of different processing stages were tested with the method. Results showed that the method can be applied in authenticity inspection of commercial products.

Abstract: Livestock provides the motive power sustaining the life of local population and small scale industries in Pakistan. Obtaining meat and milk from sheep for the human consumption and by-products such as skins, wool, hair for local use and plays key role for the economical stability and growth of the country. There is massive amount of wool sheared by local peoples in Baluchistan but due to lack of education and technical knowledge regarding the wool shearing have remained as major issue. Shearing is made on annual or biannually, but even needs certain expertise and professionalism in the sorting of wool. The textile industry of country has greater challenge for last few decades. Government needs to upgrade vocational and technical education as well as the new equipments and machinery for wool processing in the region. Several initiatives are also being carried by small and medium enterprise for the economical uplift of region particularly and country in general. Mostly obtained wool from various regions remained as major issue for its sorting and processing for finished textiles.

Abstract: It is well known that fabric handle is controllable by controlling and adjusting mechanical properties of the fabric. The handling of fabrics, on one hand, is mostly decided by the structure of the fabric, i.e. quality of yarn, yarn count, twist number, density of warp and weft, fabric weight and weave design. Such a fabric structure is represented in terms of Cover Factor. On the other hand, the handling of fabrics can also be changed through the mechanical properties by dyeing and finishing processes after weaving. The present work investigated how much influence is exerted on wool fabric by 11 sorts of chemicals generally used in dyeing and finishing processes, and how much change is exerted on the handle of processed fabrics. The experimental results were compared with the original fabric with no treatment in terms of mechanical properties relevant to KES. It was confirmed that the fabric handle greatly depended on fabric structure. Besides, the differences in the degree of damage and the hydrophilicity of wool fiber arisen from the treatments using chemicals were examined. The effect of chemicals used in dyeing and finishing processes was also investigated on the environment. Keywords: Wool, Chemical treatment, Fabric handle, KES, Environment.

Abstract: The dissolution of wool in 4g/L NaOH solution at 65°C is used to be a standard test method for the damage of wool in the processing. This suggests that alkali can cause wool keratin and the linkage between molecule chains broken. Fortunately, the dissolution of wool at low temperature is mainly limited on the surface scales because the swelling of wool in water solution at lower temperature is quite small. In this paper, the dissolution of wool in alkali solution and the changes of the fiber structure and performance at different temperature were investigated. The results showed clearly that the wool surface keratin could be dissolved in different extent with the varying of the temperature and this could be applied to develop an AOX free modification of wool for shrinkage resistance.

Abstract: In order to separate wool from cashmere efficiently, an identification method based on texture analysis was proposed in this paper. The microscopic images captured by CCD digital camera were preprocessed as the texture image. Improved Tamura texture feature were employed to analyzing the final texture images and to attaining the texture parameters. Through a large number of samples, the mathematical modeling was completed by using neural network. Experiment results indicate that texture analysis can be a feasible method to identify cashmere and wool.