Permeability properties of single jersey fabrics made of hollow yarns

In this work effect of using hollow yarns on the permeability properties of the single jersey knitted fabrics were studied. Firstly yarns were produced by ring spinning machine using cotton, viscose and acrylic fibres in the mantle and water soluble polyvinyl alcohol (PVA) fibre in the core. Single jersey fabrics were knitted and PVA core was removed subsequently by washing process to create hollow yarn. Weight, air permeability and water transmission rate properties of fabrics were measured before and after washing and compared with reference fabrics. Due to the removal of PVA fibres from the yarn core after washing treatment, air permeability and water vapour transmission rate of the all kind of single jersey fabrics which were produced with hollow yarns increased as well as weight of the fabrics decreased which will cause more comfort during any exercise. It was also found that mantle fibre type and PVA ratio have significant effect on the fabric properties.     

Impact of structural variations in hollow yarn on heat and moisture transport properties of fabrics

The use of hollow/microporous yarns plays an important role in enhancing the thermo‐physiological comfort properties of fabrics. Depending on structural variations in hollow yarn, heat and moisture regulation behaviours of fabrics can be affected significantly. In this study, three types of hollow cotton yarn fabrics, produced by introducing polyvinyl alcohol (PVA) filament in the core, PVA staple fibres in the blend and PVA filament in doubling with cotton spun yarn, are studied. All three types of pre‐hollow yarns and reference yarns are made with a variation in spinning technique (single roving/double roving) to prepare eight single jersey knitted fabrics. The hollow/microporous structure of the yarn is created by dissolving the PVA fibres using hot washing of the fabrics. On overall evaluation of the fabric’s thermo‐physiological comfort properties, the doubled hollow yarn fabrics are found to be better than other fabrics. In general, thermal resistance, thermal absorptivity, wicking and drying properties of all types of hollow yarn fabrics increase after repeated laundering, while air permeability, water vapour permeability and water absorbency of hollow yarn fabrics mostly decrease. In contrast with fabrics made from yarn produced through single roving technique, use of double roving technique only improves fabric water vapour permeability.     

The effect of core-sheath proportion on the characteristics of hollow yarns: part I mechanical properties

In the scope of this study, core yarns in the yarn count of 59 tex were produced by using cotton, viscose, wool, and polyester fibers in the sheath and different ratios of polyvinyl alcohol (PVA) in the core. After completion of yarn production on ring spinning frame, winding process was performed in order to get packages. These yarns in the form of packages were washed during a time period in order to remove PVA from the yarn structures to obtain hollow yarn structure. Yarn irregularity and yarn tensile tests were performed in the form of packages before and after washing process. As a result of these tests; it was observed that values of yarn unevenness and tensile tests were significantly influenced by the core-sheath proportion and washing process.     

Effect of structural parameters of porous yarns and fabric on air permeability and moisture transfer of double-face woven fabrics

In this study, effect of fabric structural parameters of double-face woven fabrics including kind of porous yarn namely micro-porous yarn and hollow yarn, hole size of hollow yarn, percentage of these yarns in double-face woven fabric structure, and finally weft density on air permeability and moisture transfer of woven fabrics was evaluated. These yarns were produced by using water-soluble continuous polyvinyl alcohol filaments as core part for hollow yarns and as doubling yarn in micro-porous yarn. Results revealed the effect of kind of porous yarn, hole size of hollow yarn, and weft density on air permeability and moisture transfer of woven fabrics. The percentage of porous yarns as weft did not show obvious trend. Analysis of variance was used to study the effect of these variables on air permeability and moisture transfer of double-face woven fabrics statistically.     

Novel engineering approach to optimization of thermal comfort properties of hemp containing textiles

The aim of this research was to investigate the possibilities of producing comfort hemp containing textile fabrics by assembling a pure hemp yarn with other-fibre containing yarn. The plain knitted fabrics were produced from two-assembled hemp and three variants of cotton yarns which differed in twist level, all having the same linear density. The transport properties (air permeability, water vapour permeability and thermal resistance) of the hemp-based knitted fabrics were quantitatively analysed. The results obtained demonstrated that the introduction of cotton into hemp-based textiles reduces air and water vapour permeability with the downward trend in thermal resistance. The extent to which the transport properties varied among the hemp/cotton knitted fabrics was dependent on the twist intensity of the cotton yarns. Therefore, the yarn assembling technique is an effective way not only to combine different fibre properties but to take advantage of intrinsic properties of component yarns.     

摩擦空心纱的结构特点和拉伸性能

对以PVA短纤维纱为芯纱,棉纤维为外包纤维的摩擦包芯纱,通过水煮处理去除可水溶的PVA芯纱后,制得摩擦空心纱。对摩擦空心纱以及具有加强芯纱的摩擦空心纱的结构特点和拉伸性能进行了试验研究。摩擦空心纱的结构特点是空心部分位于纱线的中心,溶芯后纱线结构膨松,直径增大。试验结果表明溶芯后摩擦空心纱的强力很低,其原因为去除了高强力的芯纱,溶芯后纱线膨胀引起纤维间抱合力减小;用涤纶长丝作为加强芯纱可以显著提高摩擦空心纱的强力。     

Physical properties of ring,compact, and air vortex yarns made of PTT/wool/modal and wearing comfort of their knitted fabrics for high emotional garments

This study examined the physical properties of PTT/wool/modal yarns according to the yarn structure and the wearing comfort of their knitted fabrics for high emotional garments. For this purpose, the air-vortex, compact, and ring yarns and their knitted fabrics were prepared to analyze the wear comfort according to the yarn structure and the possibility of applications of the PTT/wool/modal blend fibers to air-vortex yarn. The wicking and drying rates of the air-vortex yarn knitted fabrics were superior to those of the ring and compact yarns fabrics, and the heat-keeping capability of the air-vortex yarn knitted fabric was higher than those of the ring and compact yarns fabrics due to the low thermal conductivity and maximum heat flow rate. In addition, the pilling of the air-vortex yarn knitted fabric was less than those of the ring and compact ones due to the air-vortex yarn structure with parallel fibers in the core part and the periodical and fasciated twists on the sheath part of the yarns. The tactile hand of the air-vortex yarn knitted fabric was harsher than those of the ring and compact yarns knitted fabrics because of the low extensibility and compressibility, and the high bending and shear rigidities.     

驼绒／可溶性维纶包芯纱针织物的服用性能分析

采用驼绒／可溶性维纶包芯纱和纯驼绒纱线分别制备了纬平针及1＋1罗纹织物试样,测试分析了包芯纱织物退维前后及纯驼绒织物的服用性能。结果表明,驼绒／可溶性维纶包芯纱针织物退雏后尺寸稳定性良好,且透气性、保暖性、柔软性有所提高,透湿性、厚度略有减小;与纯驼绒织物相比,退维后织物的蓬松性、柔软性、保暖性较好。     

用Dref 3摩擦纺多组分纬纱织造的织物的风格特征

研究分析了3种用Dref3摩擦纺多组分纬纱织造的平纹织物的风格特征。3种不同的纬纱是：芯皮均为粘纤;水溶性PVA作皮,粘胶无捻纱条作芯;PVA无捻纱条作芯,粘纤作皮。3种纱均在Dref3型摩擦纺机上按芯皮50／50比例纺成,经纱统一采用2合股纯棉纱线。将3种纱分别织成织物,然后用热水将PVA溶解去除。织物性能的测定结果：织物性能与组成织物的纱组分性能并不一致。无捻芯纱(溶掉PVA表皮)织物具有较高的拉伸强力、撕裂强力、折皱回复性和耐磨性;而空心纱(溶掉PVA作芯)织物具有丰满、蓬松的结构和良好的耐压缩性能。     

Thermo-physiological comfort properties of double-face knitted fabrics made from different types of polyester yarns and cotton yarn

Double-face knitted fabrics with hydrophobic inner and hydrophilic outer layers are characterised by their advantageous thermo-physiological comfort property that facilitates the transport of sweat from skin to outer fabric layer where it can be evaporated easily. In this study, for the production of double-face knitted fabrics, cotton yarn as hydrophilic yarn type and five different polyester filament yarns consisting of standard polyester, hollow polyester, micro polyester, textured polyester and textured micro polyester as hydrophobic yarn type were used. In order to determine the thermo-physiological comfort properties of the fabrics, air permeability, water vapour permeability, thermal conductivity, thermal resistance and overall moisture management capacity were measured. The results were comparatively analysed using statistical methods. The experimental results demonstrated that the polyester-type yarns and the combinations of them with the cotton yarn in fabric layers affected the thermo-physiological comfort properties significantly. The fabrics with polyester-type inner face and cotton outer face showed the best moisture transmission properties.     

仪纶~(TM)纬平针织物的抗起毛起球性能

本文分别选用环锭纺、赛络纺、赛络紧密纺纺纱工艺,制备了同等纱支的仪纶~(TM)纯纺、仪纶~(TM)/棉(65/35)混纺针织纱线及其纬平针织物,对比测试了纱线性能及其织物抗起毛起球性能。实验结果显示:不同纺纱工艺的仪纶~(TM)针织纱线总体性能相似,赛络紧密纺纱线纱体结构更均匀;赛络纺织物的抗起毛起球性较环锭纺织物高0.5级,赛络紧密纺织物的抗起毛起球性明显好于环锭纺织物;混纺织物的抗起毛起球等级和起球粒数均有所改善。     

Comparison of fabric properties knitted by pin spacer compact and conventional compact yarns

This study examined the influence of pin spacer apparatus attachment on compact yarn quality parameters and physical properties of knitted fabrics manufactured using those 100% cotton compact yarns. Two groups of compact yarns were spun on regular compact yarn spinning frame with and without addition of pin spacer apparatus which is placed at the end of the drawing unit of regular compact yarn spinning frame. Totally eight yarns were spun at four different yarn number levels (Ne 24/1, Ne 30/1, Ne 36/1 and Ne 40/1) and two different spinning conditions (with and without pin spacer apparatus). Spun yarn types were then knitted on the industrial sized plain knitting machine. Knitted fabrics were used in the greige and dyed form to evaluate their bursting strength (kPa), dimensional change, abrasion related mass loss (%), pilling resistance, air permeability (mm/s) and colour difference. Test results were then statistically evaluated and influence of pin spacer attachment on yarn quality parameters and fabric properties was determined. In the frame of this experimental work, attachment of pin spacer apparatus improved compact yarn characteristics especially at yarn evenness, imperfection and hairiness values. In case of knitted fabric properties, it was found that pin spacer apparatus attached compact yarn utilization significantly improved air permeability properties of knitted fabrics.     

Characterization of fabric properties knitted from multifilament polyester textured yarns with various number of filaments

The purpose of this study is to investigate the physical and mechanical properties of fabrics knitted from textured polyester multifilament yarns with various numbers of filaments in the yarn cross-section. In this regard, some of the characteristics of yarns and fabrics, knitted from the mentioned yarns, were measured and analysed. Analysis of results showed that increasing the number of filaments in the yarn cross-section leads to a decrease in yarn’s diameter and abrasion resistance. Moreover, examining the properties of the weft-knitted fabrics revealed that increasing the number of filaments causes a rising trend in the compressibility and bursting strength of fabric. On the contrary, the thickness, air permeability and abrasion resistance decreases due to a growth in the number of filaments. A decline in the strength and elongation of yarns and fabrics produced from them is also another result of increasing the number of filaments in the yarn cross section.     

Comparison of thermal comfort properties of single jersey fabrics produced by hollow yarns with different hollowness ratio

In this study, the thermal comfort properties of single jersey fabrics produced by conventional and hollow cotton yarns with different hollowness ratio have been investigated and compared. For this purpose, thermal conductivity, thermal resistance, thermal absorptivity, air permeability and water vapour permeability of core spun, hollow and conventional yarn fabrics were measured and evaluated statistically. It was observed that thermal comfort properties of single jersey fabrics were affected by the yarn structure and the fibre distribution within the yarn. The results showed that hollow yarn fabrics had better thermal comfort properties than that of conventional yarn fabrics. In hollow yarns, as the hollowness ratio increases, air permeability and thermal conductivity of single jersey fabrics decrease but thermal resistance, thermal absorptivity and water vapour permeability increase. Statistical analysis also indicated that the differences between properties of hollow yarn fabrics and conventional yarn fabrics were significant. Furthermore, the yarn hollowness ratio significantly affects thermal comfort properties of single jersey fabrics.     

多重集聚纺纱结构成形机制及其针织物性能

为解决多毛羽传统环锭纱针织困难,而光洁的常规集聚纺纱线织物手感硬的技术难题,建立串联半开放式多重集聚纺纱方法,分析多重集聚纺纱机制和结构成形特征。理论分析结果表明,多重集聚纺纱线具有外紧而内柔的结构特征。基于理论解析,在相同工艺条件下,分别采用传统环锭、常规集聚和多重集聚纱线制成针织面料,对比分析了各针织物压缩回弹、透气、抗起毛起球、耐磨、染色等性能。测试结果表明：与传统环锭纱相比,多重集聚纱线针织物耐磨、透气性、抗起毛起球性改善;与常规集聚纱线相比,多重集聚纱线针织物悬垂性、压缩回弹性和染色性能明显提高。     

低扭矩环锭纺纱原理及其单纱的结构和性能

本文主要回顾了低扭矩环锭纺纱技术的发展。通过讨论其纺纱三角区的特点,利用高速摄影技术对纺纱区捻度和张力分布的观察分析,系统地介绍了低扭矩纱的成纱原理。此外,结合示踪纤维技术,利用纱线结构连续测量分析系统对低扭矩环锭单纱和传统环锭单纱的内部结构进行分析,揭示了低扭矩纱独特的结构特点,如非同轴异形螺旋线结构,纤维片段局部反转现象等。这些特点解释了低扭矩纱及其织物具有优良物理性能的原因。同时,通过多个生产厂家提供的测试数据,对比分析了几代低扭矩环锭纱与传统环锭纱及其织物的物理性能,结果表明低扭矩环锭纱具有低捻高强、低残余扭矩和毛羽少等特点,其针织物经多次水洗后歪斜变形小和手感好,机织物具有较好的撕裂强力,断裂强力和耐磨擦性。最新一代低扭矩环锭纺纱技术显著地改善了高支纯棉纱的物理性能。     

Modelling to predict thermophysiological properties of hollow/microporous yarn fabrics

Hollow/microporous yarn spinning is a technique used to increase the bulk of yarn without increasing its weight. Hollowness in the cotton yarns has been introduced by various methods and techniques. Empirical models have been developed to predict the thermophysiological properties through structural parameters. Based on standardized multiple linear regression models, fabric’s structural parameters are related with thermophysiological properties of hollow yarn fabrics. Three basic parameters i.e. yarns packing density, inter-yarn porosity and fabric thickness have been found to relate strongly with fabric thermophysiological properties except water vapour permeability.     

Optimization of spinning parameters influencing the characteristics of structurally modified viscose yarn

Yarn structure influences the configuration of the constituent fibers in the yarn and the comfort properties of the fabrics to a great extent. The fiber arrangement in the yarn has a major influence on the comfort-related properties such as thermal conductivity, air permeability, wickability, and moisture vapor permeability. This study dealt with the influence of process and material variables namely, polyvinyl alcohol (PVA) proportion, twist multiplier (TM), and spindle speed on microporous viscose yarn properties. Three-variable three-factor Box and Behnken method was used to investigate the individual and interaction effects of selected variables on yarn properties. The selected variables have a significant influence on all the yarn properties. The increase in PVA%, spindle speed, and TM reduces the specific volume and wickability of yarns and increases the tenacity and packing factor of yarns before dissolving the PVA fibers. With increase in spindle speed and TM, same trend was noticed after dissolving the PVA also. But the trend reverses with increase in PVA percentage after dissolution of PVA fiber. The increase in PVA percentage increases the specific volume and wickability of yarns and decreases the tenacity and packing factor of yarns after dissolution of PVA fiber. The optimized process parameters were obtained, and yarn was spun with the optimized parameters to validate the model.     

A study on thermal properties of single-jersey knitted fabrics produced from ring and compact folded yarns

This paper presents a study on the thermal properties of single-jersey knitted fabrics manufactured using ring, compact and ring/compact folded yarns. The variations in thermal properties depending on the yarn twist and traveller weight of folded yarn single-jersey knits were discussed. It was found that the thermal resistance of knitted fabrics generally increases as the traveller weight decreases, and also water vapour permeability reduces as the traveller weight decreases. The water vapour permeability and air permeability of knitted fabrics increase as the twist increases. The thermal conductivity of knitted fabrics decreases as the twist increases. The air permeability and water vapour permeability values were higher for compact folded yarn fabrics as compared to those values of ring and ring/compact folded yarn fabrics. It is observed that yarn twist and traveller weight have affected different thermal properties of single-jersey folded yarn fabrics.     

基于包芯纱的空芯纱加工技术

以PVA长丝或短纤为芯纱，棉纤维为外包纱生产包芯纱，并通过退维得到空芯纱，由这种空芯纱制织的织物具有许多优良的性能。文章探讨了在传统环锭细纱机上生产包芯纱，并通过退维处理得到空芯纱的加工技术；并对空芯纱织物的透气性和厚度等进行了测试与分析。