Variation in the softness and fibre curvature of cashmere,alpaca, mohair and other rare animal fibres

Softness of apparel textiles is a major attribute sought by consumers. There is surprisingly little objective information on the softness properties of rare animal fibres, particularly cashmere, alpaca and mohair. Samples of these and other rare animal fibres from different origins of production and processors were objectively measured for fibre diameter, fibre curvature (FC, crimp) and resistance to compression (softness). While there were curvilinear responses of resistance to compression to FC and to mean fibre diameter, FC accounted for much more of the variance in resistance to compression. Fibre type was an important determinant of resistance to compression. The softest fibres were alpaca, mohair and cashgora and all of the fibres measured were softer than most Merino wool. Quivet, llama, camel, guanaco, vicuña, yak wool, bison wool, dehaired cow down and Angora rabbit were also differentiated from alpaca, mohair and cashmere. There were important differences in the softness and FC of cashmere from different origins with cashmere from newer origins of production (Australia, New Zealand and USA) having lower resistance to compression than cashmere from traditional sources of China and Iran. Cashmere from different origins was differentiated on the basis of resistance to compression, FC and fibre diameter. Cashgora was differentiated from cashmere by having a lower FC and lower resistance to compression. There were minority effects of colour and fibre diameter variation on resistance to compression of cashmere. The implications of these findings for the identification and use of softer raw materials are discussed.     

Comparisons of the Fourier Transform Infrared Spectra of cashmere,guard hair,wool and other animal fibres

Fourier Transform Infrared Spectroscopy (FTIR), identifies chemical bands related to chemical bonds including amino acid groups. The potential for FTIR to differentiate animal fibres from different origins was investigated using cashmere (Chinese, Australian, Iranian), wool (Chinese, Australian), bison wool, qiviut from Musk-ox, vicuña and guard hairs present in these raw fibre samples. Cashmere from a controlled nutrition experiment with known amino acid composition was included in the study. While the intensity of FTIR spectra were moderately correlated with the content of some of the amino acids in cashmere, this investigation did not detect any significant systematic effects of nutritional manipulation of cashmere goats on the FTIR spectra of their cashmere. Significant differences were detected in the intensity of FTIR spectra between cashmere and wool, cashmere from different origins, white and coloured cashmere, and between cashmere and hair. The FTIR spectra of cashmere and wool overlapped with those of bison, qiviut and vicuña. The intensity of FTIR spectra were not correlated with the mean fibre diameter of samples but the intensity of most spectra bands were positively correlated with the fibre curvature of the samples (r = 0.27–0.38). Based on these results it does not seem likely that FTIR spectra offer a reliable method to distinguish between pure cashmere and blends of cashmere with wool or other animal fibre for diagnostic tests to determine the fibre composition in finished textiles.     

Cuticle and cortical cell morphology and the ellipticity of cashmere are affected by nutrition of goats

Cuticle scale edge height and frequency are used to identify animal fibres but exhibit a large range in dimensions, the reasons for which have not been elucidated. Cuticle and cortical cell dimensions along with the ellipticity of fibres were investigated in cashmere samples from a controlled nutrition experiment. Cuticle scale frequency, cuticle thickness, cortical cell dimensions and ellipticity were affected by nutritional treatment, with significant differences between cashmere from goats fed to grow and those which maintained live weight or lost weight. Cuticle scale frequency, cell thickness and ellipticity (contour) varied with fibre diameter, fibre growth rate and the size of the animals. Cuticle thickness and ellipticity were related. Cashmere grown by goats with higher levels of nutrition had longer cortical cells with greater diameter, volume and a higher length:diameter ratio compared with cashmere grown by goats in restricted nutrition treatments. The results show that the fundamental physical structures of cashmere do not have fixed dimensions. The consequences of the variations in cuticle morphology and ellipticity will be variation in surface friction, bending rigidity, softness, lustre, colour attributes, fibre cohesion during processing, felting and wear properties of textiles. There are also important consequences upon the determination of cashmere origin.     

Weathering,fibre strength and colour properties of processed white cashmere

Weathering refers to the degradation of wool fibres that occur during growth from exposure of the fleece to sunlight, water and air. Weathering damage to Merino wool reduces quantities of fibre that are harvested, reduces length in both raw and processed wools, reduces spinning performance and dyeing outcomes. This work aimed to aimed to quantify if and to what extent weathering occurred in 38 lots of commercial dehaired white cashmere and cashmere top sourced from traditional and new origins of production and the extent of any association between weathering and tensile strength properties of the dehaired cashmere and cashmere top. The cashmere was tested for physical properties, bundle tenacity and extension, tristimulus values brightness (Y) and yellowness (Y-Z) and reflectance. Dye uptake was used as an index of weathering. Linear models, relating to weathering, bundle tenacity and Y-Z were fitted to origin and other objective measurements. Mean attributes (range) were: mean fibre diameter, 17.0 μm (13.5–21.3?μm); bundle tenacity of tops, 10.3 cN/tex (8.3–12.9?cN/tex), for dehaired fibre, 10.1 cN/tex (9.1–11.4 cN/tex). Stain uptake varied from 0.92 to 6.34 mg/g fibre indicating a six-fold variation in the extent of weathering. Both the extent of weathering and the bundle tenacity of commercial lots of cashmere were affected by the origin of the cashmere. Increased weathering reduced bundle tenacity, bundle extension, increased the yellowness and reduced reflectance of white cashmere. Bundle tenacity of cashmere declined as fibre diameter variability increased from 20 to 22.5%. For the samples tested, the cashmere from China, Mongolia, Afghanistan and Iran showed more weathering than cashmere from Australia, New Zealand and the USA. The differences in the extent of weathering and of bundle tenacity between cashmere from different origins were of commercial significance.     

羊绒、羊毛（改性羊毛）的定性鉴别与定量分析

从羊毛及羊绒的组织结构及物理,化学特性方面的差异进行分析,结合实际生产情况,总结了染色法,着色剂法,溶液鉴别法,电子显微镜观察法等定性与定量鉴别羊毛（改性羊毛）与羊绒的原理和方法。     

基于基因技术的羊绒与羊毛纤维定性鉴别方法

随着羊毛改性技术的发展,传统的光学显微镜鉴别羊绒羊毛的方法逐渐显出其局限性。采用基因技术,利用山羊与绵羊之间特定碱基序列的差别,通过PCR扩增、测序,得到各自的DNA碱基序列,从而确定其种属,达到鉴别纤维的目的。文章通过纯羊绒羊毛纤维及不同比例羊绒羊毛混合物线粒体DNA的测序实验,研究了羊绒羊毛的DNA鉴别方法。结果表明：1）基于基因技术的DNA测序方法可以准确定性鉴别极小比例的羊绒羊毛纤维;2）对于纯羊绒羊毛纤维,采用一组引物,即可通过特定位点特征碱基序列组来鉴别;3）对于羊绒羊毛混合物,分别采用羊绒引物和羊毛引物对样品测序,通过查找羊绒羊毛纤维各自的特征序列,鉴别样品中是否含有羊绒或羊毛。     

羊绒与羊毛的碱溶度差异

对羊绒及羊毛在不同条件 (碱浓度、温度、处理时间 )的 Na OH溶液中的溶解度进行了测试、分析和说明 ,进一步了解碱对羊绒和羊毛不同的作用情况 ,得出了羊绒 /羊毛含量定量分析的条件 ,以便在生产和检验中加以利用。     

山羊绒纤维的拉伸性能

研究了山羊绒纤维的拉伸性能以及单纱的拉伸松弛性能,并与细支羊毛纤维进行对比。研究结果表明:山羊绒纤维的比强度、拉伸模量,松弛时间高于羊毛;在较小定伸长条件下,山羊绒纱线拉伸应力松弛速率慢于羊毛纱线,即山羊绒纱线比羊毛纱线难定形,这些力学性能的差异是由于山羊绒纤维α-结晶度高于羊毛;在80~130℃干热条件下,山羊绒纱线的拉伸应力松弛速率及其定形率均随温度的提高而提高;当温度高于120℃时,提高不显著。     

山羊绒原料含量的鉴定

山羊绒原料含绒量的鉴定很大程度上取决于分析人员的工作经验和对各种纤维的认别能力。文章对山羊绒及各种近似的动物纤维的表面形状及超微结构进行对比分析，并将其作为定量分析原料中含绒量的基础。     

山羊绒与绵羊毛的鉴别与实践

针对绵羊毛影响山羊绒检测误差与误判这一难题,利用现代纺织理论与测试技术,对山羊绒与绵羊毛的表面形态结构进行了剖析,从山羊绒与绵羊毛的鳞片形态、鳞片变异特征、粗细绵羊毛与山羊绒表面形态的异同性等方面进行了多角度的比较,结合多年生产实践经验,探寻了山羊绒与绵羊毛团的区别,洗净后山羊绒与绵羊毛的区别,提出了进厂无毛绒宏观检验与微观检验理念和具体操作方法,对确保无毛绒质量,减小鉴别误差和检验误判具有现实的指导意义.     

羊绒混纺织物与纯毛织物的服用舒适性分析

文章从舒适的观点分析比较了羊绒／羊毛精混纺织物与纯毛织物的服用性能，并根据羊绒纤维的特性，通过试验对触感舒适和热湿舒适性方面进行了分析。由综合测评结果可知，羊绒混纺织物较之纯毛织物轻柔，手感滑糯，吸湿性和保暖性特别好，弹性好，外观细腻丰满，富有光泽，穿着滑爽舒适。     

Validation of UPLC/ESI-MS method used for the identification and quantification of wool,cashmere and yak fibres

The method based on the ultra-performance liquid chromatography coupled with electrospray mass spectrometry (UPLC/ESI–MS) instrument was used for the identification and quantification of the most commercial Bovidae fibres (wool, cashmere and yak). In the present paper, this method was developed and validated by the authors and confirmed by many analyses of, known and unknown, wool/cashmere/yak blends at different stages of manufacture (fibres, slivers, yarns, fabrics, and raw materials) and with different treatments (dyed, depigmented, bleached, finished forms).     

Cuticle and cortical cell morphology of alpaca and other rare animal fibres

The null hypothesis of the experiments reported is that the cuticle and cortical morphology of rare animal fibres are similar. The investigation also examined if the productivity and age of alpacas were associated with cuticle morphology and if seasonal nutritional conditions were related to cuticle scale frequency. Cuticle and cortical cell dimensions and ellipticity of the fibre cross section were investigated in 32 samples of cashmere, alpaca, mohair, bison, qiviut and vicuña from various origins. In addition, 24 Peruvian alpaca samples from animals ages 2–6 years and of varying fleece productivity were examined. Cuticle scale frequency, cuticle thickness and cortical cell dimensions (length, diameter, volume and ratio of length to diameter) and ellipticity differed between fibres and cuticle scale frequency also varied with mean fibre diameter. For Peruvian alpaca fleece samples, cuticle scale frequency varied with the age of alpaca and fleece productivity. Fibre ellipticity increased with increasing fibre diameter. Cortical cell length was strongly related to cortical cell diameter. The cuticle scale morphology of these rare animal fibres did not have fixed dimensions. Using cuticle scale morphology as a diagnostic tool to positively identify rare natural animal fibres needs to standardize measurements for fibre diameter but will still be affected by differences in animal productivity.     

山羊绒/绵羊毛混纺纱的定量分析

阐述了山羊绒/绵羊毛混纺纱定量分析方法,对比分析了使用视频显微镜、显微投影仪和扫描电子显微镜,根据山羊绒、绵羊毛鳞片结构特征和纤维直径测定山羊绒/绵羊毛混纺纱纤维含量的方法和特点.测试结果表明:采用视频显微镜及与其兼容配套的Pinnacle Studio 8.0图像采集软件和Imager-Proplus图像分析软件测试山羊绒/绵羊毛混纺纱纤维含量,比显微投影仪和扫描电子显微镜测试法较为方便和快捷,且精确度较高,适合山羊绒/绵羊毛混纺纱定量分析测试.     

基于谱线特征的羊绒与羊毛的鉴别

为快速区分和检验羊毛、羊绒,提出基于羊毛与羊绒谱线特征的识别方法。这种方法先通过光学显微镜获得羊毛与羊绒的图像,然后经过图像处理得到羊毛与羊绒的表面信息。接着通过投影的方式,获得羊毛与羊绒表面所对应的谱线。对获得的谱线进行分割,根据羊毛及羊绒谱线的特性不同,提取羊毛及羊绒谱线的单元宽度值、单元峰值及离散系数、峰值宽度比等参数;最后通过对这些参数的分析处理进行识别。实验结果表明,采用这种方法识别羊毛及羊绒,不仅快速准确,而且与以往的方法相比,在精度和速度上都有显著的提高。     

采用滑溜牵伸的低比例山羊绒混纺纺纱实践

针对山羊绒与羊毛长度差异较大、牵伸隔距难以确定的问题,在JWF-1516 型棉纺环锭细纱机上采用滑溜牵伸与非滑溜牵伸的方式纺制山羊绒/羊毛混纺纱、山羊绒/ 羊毛/ 桑蚕丝混纺纱,分析滑溜牵伸与非滑溜牵伸方式纺制低比例山羊绒混纺纱的线密度和纱线质量。纺纱试验结果表明：采用滑溜牵伸与非滑溜牵伸的方式,均可纺制单纱线密度为11.1 tex 的羊毛/ 山羊绒（84/16）混纺纱与羊毛/ 山羊绒（65/35）混纺纱;与非滑溜牵伸方式相比,采用滑溜牵伸方式纺制的细纱粗节与细节明显减少;采用滑溜牵伸方式,可纺制单纱线密度为10 tex 的羊毛/ 山羊绒（84/16）混纺纱（单纱条干CV 值为19%）,和单纱线密度为8.3 tex 的羊毛/ 山羊绒/ 桑蚕丝（80/10/10）混纺纱（单纱条干CV 值为18.8%）,但这2 种线密度的混纺纱用非滑溜牵伸方式不可纺。     

羊绒与羊毛的定性鉴别与定量分析

从羊毛及羊绒的组织结构及物理、化学特性方面的差异进行分析，结合实际生产中的一些情况，总结了定性与定量地鉴别羊毛（改性羊毛）与羊绒的原理和方法。     

羊绒羊毛纤维线粒体DNA碱基对序列研究

物种不同,DNA序列亦不同,而生存环境、食物链等因素也会引起基因突变。文章对不同地区、不同种类的羊绒和羊毛纤维线粒体DNA进行测序实验,通过对实验所得序列的比较与分析,得出结论:羊绒羊毛纤维线粒体DNA序列的相似度达98%以上,但在特定的位置有各自的特征碱基序列;不同产地、不同种类的山羊绒纤维线粒体DNA的特征碱基序列基本一致,不同产地、不同类别的绵羊毛纤维线粒体DNA的特征碱基序列亦基本一致。     

基于鳞片纹图基因码的羊绒理论识别精度及正误判率

针对羊绒与细羊毛鉴别的问题,研究了鳞片纹图基因码关于羊绒的的识别精度。研究表明, 虽然羊绒与细羊毛同一鳞片纹图基因码的分布类型相同,但数字特征却大同小异,羊绒鳞片纹图基因码的数字特征表明其鳞片更似方形或窄矩形,而细羊毛的则更似宽矩形。在所有纹图基因码中,两类纤维鳞片面积、周长和矩形度的分布几乎完全重叠,表明三者无法用于纤维鉴别。两类纤维其它纹图基因码的分布部分重叠,据此可建立具有最小识别误差的纤维辨识标准,获得了羊绒纤维最大识别概率为88.8%,羊毛最大识别概率为92%,最小识别误差为10.7%的结论。这些结论为羊绒鉴别最优基因组的发现提供了理论参考。     

基于决策树算法的羊绒与羊毛纤维鉴别

山羊绒和绵羊毛（下简称羊绒与羊毛）的鉴别不仅是目前纤维检测领域中的一个热点和难点,且其鉴别研究主要是基于传统统计方法。为此,首次将数据挖掘思想引入羊绒与羊毛纤维的鉴别研究中,提出采用单根纤维上的多元指标作为分类研究的特征属性,从新的视角探索羊绒与羊毛鉴别方法。采用了四个主要的决策树算法,对羊绒和羊毛之间进行了分类,完成了相应的数学建模和评估。实验结果表明：所建模型的平均相对误差都低于6%,经对比,C5.0算法比其他算法更为精准和稳定,可用于对实际羊绒与羊毛纤维的检测分类。