V K Kothari - Academia.edu (original) (raw)
Papers by V K Kothari
A quantit ati ve analysis o f th e blend irregu lar it y of air -je t tex tured yams is reported.... more A quantit ati ve analysis o f th e blend irregu lar it y of air -je t tex tured yams is reported. Th e effect ~ of ra w Ill aterial a III I process and nozzle pa rame ters on th e blend iI1limacy of air-jet tex tured ya rn s in a rotationa l patt ern have hee n ~tudied for th e different bl end s of filament ya rn s. It has been es tabli shed that th e ind ex of blend irregul arit y is closely a~s()c i a t ed wi th th e yarn tension levels at th e ex it of the nozzle and in th e mechani cal stabi li zin g zone. Component s of di~similar fihr e charac teri st ics res ult in poo r blend intimacy. Tex turin g in wet co nditi on improves th e blend intim acy. Bl end regul arit y i ~ Air-j et texturin g process is a good method of blending continuous fi lament ya rn s. Continuous filament ya rn s of both th erm opl as ti c and non thermopl as tic types ' can be fed into th e jet simultaneously and textured togeth er. Components hav ing different shrink age potentials, tensil e prope...
Textile Research Journal, 1984
where ep and e, are the percentage strains at loads of 0.33 gf/den for the parent and textured ya... more where ep and e, are the percentage strains at loads of 0.33 gf/den for the parent and textured yarns, respectively. Wray’s method is conceptually incorrect. in the inherent assumption that the extensibility of the textured yarn is a measure of its structural integrity. The lack of validity of Wray’s assumption is exemplified. through the experimental results that follow. Effect of relaxation shrinkage on the stability of air textured yarn: A 82/20 nylon 6 yarn with a pretwist of 5.9 turns/cm was textured with 30% overfeed and 4 kgf/cm2 air pressure in an experimental air texturing unit designed in our laboratory. Following texturing, single strands of textured yarns were free relaxed in water at 90°C for 60 minutes. The strands of yarn
Fashion and Textiles, 2015
Thermo-physiological properties of textiles greatly determine the transport of heat, moisture vap... more Thermo-physiological properties of textiles greatly determine the transport of heat, moisture vapour and liquid moisture from skin to environment through clothing and are therefore, crucial to provide comfortable microclimate to the wearer. Clothing layer worn next to skin should have two important properties: the initial and the foremost property is to absorb the perspiration from the skin surface and second property is to transfer moisture to atmosphere and make the wearer feel comfortable. Diffusion and wicking are the two means by which moisture gets transferred to the atmosphere. Concentration gradient is the driving force which causes moisture diffusion from region of high concentration to low concentration. Wicking involves the motion of liquid moisture in void spaces between fibres in a yarn (Patil et al. 2009) and is significantly affected by the liquid retention in the voids. The thermal properties along with air permeability and
The Journal of The Textile Institute, 2017
The work deals with the study of the thermal resistance characteristics of nonwoven structures fo... more The work deals with the study of the thermal resistance characteristics of nonwoven structures for the cold weather clothing. The low melting point polyester fibres were mixed with the hollow polyester fibres for producing the thermal bonded waddings using a compression moulding machine. Three factor Box and Behnken design was used varying the factors namely areal density, thickness and fibre denier. Samples were tested for the thermal resistance using guarded hot plate apparatus and analyzed using Design Expert statistical software package. Layered thermal bonded waddings with different combinations were also tested for thermal resistance under forced and free convection modes.
Fibers and Polymers, 2014
ABSTRACT This paper discusses measurement and modeling of dielectric properties of polymeric mate... more ABSTRACT This paper discusses measurement and modeling of dielectric properties of polymeric materials in a three phase mixture consisting air, moisture and the polymer itself. Using nylon 6 monofilaments as base polymeric materials and assembled in simple woven fabric form, it is shown that the effective permittivity follows a quadratic curve with respect to the volume fraction. The effect of moisture absorption by the fibers on the effective volume fraction is calculated theoretically and results show negligible difference between two extreme cases of moisture adsorption. A new method of analyzing the system as a three phase system is described in this paper. © 2014 The Korean Fiber Society and Springer Science+Business Media Dordrecht.
Research Journal of Textile and Apparel, 2014
The moisture vapour permeability properties of a series of almost similar polyesterviscose (P/V) ... more The moisture vapour permeability properties of a series of almost similar polyesterviscose (P/V) and polyester-cotton (P/C) blended fabrics are investigated. The water vapour transport rate greatly differs depending on the principle of the test methods, even when other parameters are nearly identical, such as air permeability, areal density, porosity and thickness. The water absorption characteristics of fibre seem to be the most important in determining the overall water vapour transport rate. Substitution of polyester for viscose and cotton in P/V and P/C blended fabrics respectively, reduces the water transport rate of the fabrics in a long term method. It is found that the P/C blended fabrics show greater water vapour transport than the corresponding P/V fabrics when a long term test method is used; however, the P/V fabrics show relatively higher water vapour permeability than the P/C fabrics when short duration tests are carried out by using the Permetest and moisture vapour tr...
Indian Journal of Fibre and Textile Research
The present study aims at investigating the effect of face yarn linear density and back layer fib... more The present study aims at investigating the effect of face yarn linear density and back layer fibre type on the liquid transfer properties and drying behavior of single jersey plated knitted fabrics. Fabrics knitted with coarser yarns exhibit high water absorbency, slow drying capability (characterized by lower water evaporation percentage) and appear to be unsuitable for high activity levels. Polypropylene/cotton fabric is found to be the preferred choice at high activity levels owing to lower water absorption, higher trans planar wicking and higher water evaporation percentage. Plated fabrics with nylon in the next to skin layer show high water absorption, poor trans planar wicking and slow drying capability. Nylon/cotton fabrics are, therefore, found to be ineffective in providing dry microclimate next to skin and may not be suitable at high activity levels.
![Research paper thumbnail of Influence of polyester fibre shape and size on the hairiness and some mechanical properties of yarns, Vol 39 (1), [March 2014], pp 24-32](https://attachments.academia-assets.com/86333641/thumbnails/1.jpg)
](Indian Journal of Fibre and Textile Research
Polyester fibres of different linear densities and cross-sectional shapes have been spun on ring ... more Polyester fibres of different linear densities and cross-sectional shapes have been spun on ring frame at different twist levels. These yarn samples are subjected to the deformation both in tensile and bending mode to investigate the yarn behavior as a consequence of change in cross-sectional shape and fineness of polyester fibres. Young’s modulus as well as bending rigidity of yarns increases with the increase in fibre linear density. These properties of yarns made of trilobal and tetrakelion fibres are higher in magnitude than those of their corresponding circular fibres, whereas the behaviour is opposite if scalloped oval fibre is dealt. As far as yarn hairiness is concerned, the higher the polyester fibre denier, the higher will be the hairiness count. Yarns made of scalloped oval fibres exhibit maximum numbers of hairs followed by tetrakelion and the circular fibres yarns respectively. Similarly the yarns of trilobal fibres are more hairy than their counterparts made of circula...
Heat-setting of parallel-end air-jet textured yarns produced from filament feed yarns with differ... more Heat-setting of parallel-end air-jet textured yarns produced from filament feed yarns with different shrinkage potential under conditions of const. overfeed in the heater zone and const. winding tension were studied. Increasing the shrinkage difference between the feed yarns, increases the phys. bulk and instability initially in case of yarns produced with const. overfeed in the heat-setting zone but after a certain level of shrinkage difference further increase in shrinkage difference leads to a decrease in phys. bulk and instability. The opposite trend in phys. bulk and instability was obsd. for yarns produced at const. winding tension on the Eltex AT/HS air-jet texturing machine. Air-jet textured yarns produced at const. winding tension produce yarn with higher phys. bulk, higher instability, lower tenacity, and higher elongation.
Fibers and Polymers, 2015
Establishment of similarities between proteins is very important for the study of the relationshi... more Establishment of similarities between proteins is very important for the study of the relationship between sequence, structure and function and for the analysis of evolutionary relationships. Motif-based search methods play a crucial role in establishing the connections between proteins that are particularly useful for distant relationships. This paper reports SCANMOT, a web-based server that searches for similarities between proteins by simultaneous matching of multiple motifs. SCANMOT searches for similar sequences in entire sequence databases using multiple conserved regions and utilizes intermotif spacing as restraints. The SCANMOT server is available via
Polyesters and Polyamides, 2008
Publisher Summary Fibers are the building blocks of textile materials and there is a strong corre... more Publisher Summary Fibers are the building blocks of textile materials and there is a strong correlation between the fiber properties and properties of resultant textile products. The major end-use application of textile fibers is its use in apparel fabrics. Invention of synthetic fibers especially polyamide and polyester and fiber engineering can produce, modify, and tailor fibers in ways far beyond the performance limits of fibers drawn from silkworm cocoon, grown in the fields or spun from the fleece of animals. Polyester fiber has good easy care properties and polyamide fibers have better elastic properties. The yarns are either woven or knitted to develop fabrics. Today's apparel fabric maximizes enjoyment and comfort in indoors as well as outdoors and in any kind of weather. Waterproof, windproof, and breathable through different finishing processes are just a few of many properties in demand. Therefore, stretch properties can be imparted to polyamide fibers using textured nylon in combination with elastane yarns. Certain desired properties can be built into polyester and polyamide fibers during production. However, polyamide seems to be losing its share to polyester, overwhelmed by sheer volume if not performance. Many woven industrial and apparel fabrics seem to favor polyester. Polyamide's dyeability is an advantage, but not sufficiently so to overcome the supply and variants available in polyester.
Photodermatology, Photoimmunology & Photomedicine, 2010
Introduction: Cotton fabrics used in summer do not often provide good protection against solar ul... more Introduction: Cotton fabrics used in summer do not often provide good protection against solar ultraviolet (UV) radiation. Heavy cotton fabrics can provide good protection against UV radiation. However, heavy fabrics are not good from a comfort point of view as the air permeability and moisture vapour transmission rate is very low. Objectives: To engineer cotton fabrics which will provide maximum UV protection without sacrificing the minimum requirement of air permeability and thermal resistance for a particular climatic condition. Methods: Sixteen plain and sixteen twill woven fabrics were manufactured using different cotton yarn count and picks per cm. Nonlinear regression models were developed to relate the fabric parameters with the ultraviolet protection factor (UPF), air permeability and thermal resistance. Optimization problems were formulated for UPF maximization keeping air permeability and thermal resistance as constraints. Optimization problems were solved to find out the values of yarn count and picks per cm. New fabrics were then woven using optimized combinations of yarn count and picks per cm, and error assessment between the target and the achieved fabric properties was performed. Results: The target, optimized and achieved fabric properties are showing good association. When air permeability requirement is high, the engineered cotton fabric can provide good UV protection (UPF 4 15). When the air permeability requirement is low, the engineered cotton fabric can provide excellent UV protection (UPF 4 40). Conclusions: It is possible to engineer cotton fabrics to maximize the UV protection without compromising with the comfort properties.
Textile Research Journal, 2009
A lockstitch is formed by the interlacement of needle and bobbin threads. During high-speed sewin... more A lockstitch is formed by the interlacement of needle and bobbin threads. During high-speed sewing, needle thread is subjected to repeated tensile stresses, heat, bending, pressure, torsion, and wearing. Therefore, the mechanical properties of thread, which become altered during sewing, are very important for its performance and durability. In order to design a sewing machine and threads for maximum strength retention, it is important to understand how the mechanical properties of the thread change as it progresses through the machine and become incorporated into the seam. In this paper, the tensile properties of the needle thread are measured at four sewing stages: before sewing, after dynamic loading at the tension regulator, after passage through the needle and fabric, and after bobbin thread interaction. Mercerized cotton, polyester staple spun, polyester—cotton core spun, and polyester—polyester core spun threads are used and the contribution of dynamic loading, passage through...
Textile Research Journal, 1996
Three POY yarns of 80/100, 80/48, and 80/34 denier/filament are textured with four variables at f... more Three POY yarns of 80/100, 80/48, and 80/34 denier/filament are textured with four variables at five levels. The Box-Hunter statistical experimental design is used to produce thirty-six samples in each case. The effects of texturing variables—draw ratio, disc surface speed to yam speed ratio ( D/Y ratio), first heater temperature and heater contact time on tensile properties, crimp characteristics, dye uptake, broken filaments, and tight spots—are studied. First heater temperature and draw ratio have a significant influence oh tensile, crimp, and dyeing properties. With increased D/Y ratio, broken filaments decrease but tight spots increase. A proper selection of the D/Y ratio gives acceptable levels of broken filaments and tight spots.
Textile Research Journal, 1991
ABSTRACT
Textile Research Journal, 1990
ABSTRACT We describe laundering and wrinkling trials on woven grey and dyed fabrics made from air... more ABSTRACT We describe laundering and wrinkling trials on woven grey and dyed fabrics made from air-jet textured cotton/filament composite yams as weft. The tensile and bursting strength properties of the fabrics are not affected much by the laundering treatments. The textured yarn grey fabrics in general show higher relaxation with laundering, resulting in increased thickness, thermal insulation, and abrasion resistance, and re duced air permeability and tear strength. The greater strain relief due to laundering of the bulkier textured yam structure also helps to improve the crease recovery and wrinkling properties of these fabrics. Fabrics made with textured yams show higher wrinkle recovery than the parent yarn fabrics at various strain levels. The extent of whiteness gain in grey fabrics and color loss in dyed fabrics is almost the same in both the parent and textured yarn fabrics as a consequence of laundering treatments. The textured yarn fabrics, however, show higher color value than those from the parent yarn.
The Journal of The Textile Institute, 1976
Journal of the Textile Institute, 1996
A study to characterize the structure of air-jet textured yarn in terms of its migration paramete... more A study to characterize the structure of air-jet textured yarn in terms of its migration parameters has been carried out by using the tracer fibre technique. An attempt has been made to establish the relationship between the migration parameters and the properties of air-jet textured yarns using polyester (dry and wet textured), nylon (wet textured) and polypropylene (wet textured) yarns.Physical bulk, instability, loop size, loop frequency, tenacity, breaking elongation and initial modulus were measured for various air-jet textured yarns produced using different air pressures. Migration was found to be highest in polyester (wet textured) yarns followed by wet textured polypropylene and nylon yarns. It was observed that physical bulk, loop frequency and initial modulus increases with increasing migration parameters, while tenacity, instability and breaking elongation decreases with migration parameters.Yarns produced from all three materials show similar trends. Bearing in mind the differences in dpf, the polyester feed materials showed relatively higher migration and better properties.
A quantit ati ve analysis o f th e blend irregu lar it y of air -je t tex tured yams is reported.... more A quantit ati ve analysis o f th e blend irregu lar it y of air -je t tex tured yams is reported. Th e effect ~ of ra w Ill aterial a III I process and nozzle pa rame ters on th e blend iI1limacy of air-jet tex tured ya rn s in a rotationa l patt ern have hee n ~tudied for th e different bl end s of filament ya rn s. It has been es tabli shed that th e ind ex of blend irregul arit y is closely a~s()c i a t ed wi th th e yarn tension levels at th e ex it of the nozzle and in th e mechani cal stabi li zin g zone. Component s of di~similar fihr e charac teri st ics res ult in poo r blend intimacy. Tex turin g in wet co nditi on improves th e blend intim acy. Bl end regul arit y i ~ Air-j et texturin g process is a good method of blending continuous fi lament ya rn s. Continuous filament ya rn s of both th erm opl as ti c and non thermopl as tic types ' can be fed into th e jet simultaneously and textured togeth er. Components hav ing different shrink age potentials, tensil e prope...
Textile Research Journal, 1984
where ep and e, are the percentage strains at loads of 0.33 gf/den for the parent and textured ya... more where ep and e, are the percentage strains at loads of 0.33 gf/den for the parent and textured yarns, respectively. Wray’s method is conceptually incorrect. in the inherent assumption that the extensibility of the textured yarn is a measure of its structural integrity. The lack of validity of Wray’s assumption is exemplified. through the experimental results that follow. Effect of relaxation shrinkage on the stability of air textured yarn: A 82/20 nylon 6 yarn with a pretwist of 5.9 turns/cm was textured with 30% overfeed and 4 kgf/cm2 air pressure in an experimental air texturing unit designed in our laboratory. Following texturing, single strands of textured yarns were free relaxed in water at 90°C for 60 minutes. The strands of yarn
Fashion and Textiles, 2015
Thermo-physiological properties of textiles greatly determine the transport of heat, moisture vap... more Thermo-physiological properties of textiles greatly determine the transport of heat, moisture vapour and liquid moisture from skin to environment through clothing and are therefore, crucial to provide comfortable microclimate to the wearer. Clothing layer worn next to skin should have two important properties: the initial and the foremost property is to absorb the perspiration from the skin surface and second property is to transfer moisture to atmosphere and make the wearer feel comfortable. Diffusion and wicking are the two means by which moisture gets transferred to the atmosphere. Concentration gradient is the driving force which causes moisture diffusion from region of high concentration to low concentration. Wicking involves the motion of liquid moisture in void spaces between fibres in a yarn (Patil et al. 2009) and is significantly affected by the liquid retention in the voids. The thermal properties along with air permeability and
The Journal of The Textile Institute, 2017
The work deals with the study of the thermal resistance characteristics of nonwoven structures fo... more The work deals with the study of the thermal resistance characteristics of nonwoven structures for the cold weather clothing. The low melting point polyester fibres were mixed with the hollow polyester fibres for producing the thermal bonded waddings using a compression moulding machine. Three factor Box and Behnken design was used varying the factors namely areal density, thickness and fibre denier. Samples were tested for the thermal resistance using guarded hot plate apparatus and analyzed using Design Expert statistical software package. Layered thermal bonded waddings with different combinations were also tested for thermal resistance under forced and free convection modes.
Fibers and Polymers, 2014
ABSTRACT This paper discusses measurement and modeling of dielectric properties of polymeric mate... more ABSTRACT This paper discusses measurement and modeling of dielectric properties of polymeric materials in a three phase mixture consisting air, moisture and the polymer itself. Using nylon 6 monofilaments as base polymeric materials and assembled in simple woven fabric form, it is shown that the effective permittivity follows a quadratic curve with respect to the volume fraction. The effect of moisture absorption by the fibers on the effective volume fraction is calculated theoretically and results show negligible difference between two extreme cases of moisture adsorption. A new method of analyzing the system as a three phase system is described in this paper. © 2014 The Korean Fiber Society and Springer Science+Business Media Dordrecht.
Research Journal of Textile and Apparel, 2014
The moisture vapour permeability properties of a series of almost similar polyesterviscose (P/V) ... more The moisture vapour permeability properties of a series of almost similar polyesterviscose (P/V) and polyester-cotton (P/C) blended fabrics are investigated. The water vapour transport rate greatly differs depending on the principle of the test methods, even when other parameters are nearly identical, such as air permeability, areal density, porosity and thickness. The water absorption characteristics of fibre seem to be the most important in determining the overall water vapour transport rate. Substitution of polyester for viscose and cotton in P/V and P/C blended fabrics respectively, reduces the water transport rate of the fabrics in a long term method. It is found that the P/C blended fabrics show greater water vapour transport than the corresponding P/V fabrics when a long term test method is used; however, the P/V fabrics show relatively higher water vapour permeability than the P/C fabrics when short duration tests are carried out by using the Permetest and moisture vapour tr...
Indian Journal of Fibre and Textile Research
The present study aims at investigating the effect of face yarn linear density and back layer fib... more The present study aims at investigating the effect of face yarn linear density and back layer fibre type on the liquid transfer properties and drying behavior of single jersey plated knitted fabrics. Fabrics knitted with coarser yarns exhibit high water absorbency, slow drying capability (characterized by lower water evaporation percentage) and appear to be unsuitable for high activity levels. Polypropylene/cotton fabric is found to be the preferred choice at high activity levels owing to lower water absorption, higher trans planar wicking and higher water evaporation percentage. Plated fabrics with nylon in the next to skin layer show high water absorption, poor trans planar wicking and slow drying capability. Nylon/cotton fabrics are, therefore, found to be ineffective in providing dry microclimate next to skin and may not be suitable at high activity levels.
Indian Journal of Fibre and Textile Research
Polyester fibres of different linear densities and cross-sectional shapes have been spun on ring ... more Polyester fibres of different linear densities and cross-sectional shapes have been spun on ring frame at different twist levels. These yarn samples are subjected to the deformation both in tensile and bending mode to investigate the yarn behavior as a consequence of change in cross-sectional shape and fineness of polyester fibres. Young’s modulus as well as bending rigidity of yarns increases with the increase in fibre linear density. These properties of yarns made of trilobal and tetrakelion fibres are higher in magnitude than those of their corresponding circular fibres, whereas the behaviour is opposite if scalloped oval fibre is dealt. As far as yarn hairiness is concerned, the higher the polyester fibre denier, the higher will be the hairiness count. Yarns made of scalloped oval fibres exhibit maximum numbers of hairs followed by tetrakelion and the circular fibres yarns respectively. Similarly the yarns of trilobal fibres are more hairy than their counterparts made of circula...
Heat-setting of parallel-end air-jet textured yarns produced from filament feed yarns with differ... more Heat-setting of parallel-end air-jet textured yarns produced from filament feed yarns with different shrinkage potential under conditions of const. overfeed in the heater zone and const. winding tension were studied. Increasing the shrinkage difference between the feed yarns, increases the phys. bulk and instability initially in case of yarns produced with const. overfeed in the heat-setting zone but after a certain level of shrinkage difference further increase in shrinkage difference leads to a decrease in phys. bulk and instability. The opposite trend in phys. bulk and instability was obsd. for yarns produced at const. winding tension on the Eltex AT/HS air-jet texturing machine. Air-jet textured yarns produced at const. winding tension produce yarn with higher phys. bulk, higher instability, lower tenacity, and higher elongation.
Fibers and Polymers, 2015
Establishment of similarities between proteins is very important for the study of the relationshi... more Establishment of similarities between proteins is very important for the study of the relationship between sequence, structure and function and for the analysis of evolutionary relationships. Motif-based search methods play a crucial role in establishing the connections between proteins that are particularly useful for distant relationships. This paper reports SCANMOT, a web-based server that searches for similarities between proteins by simultaneous matching of multiple motifs. SCANMOT searches for similar sequences in entire sequence databases using multiple conserved regions and utilizes intermotif spacing as restraints. The SCANMOT server is available via
Polyesters and Polyamides, 2008
Publisher Summary Fibers are the building blocks of textile materials and there is a strong corre... more Publisher Summary Fibers are the building blocks of textile materials and there is a strong correlation between the fiber properties and properties of resultant textile products. The major end-use application of textile fibers is its use in apparel fabrics. Invention of synthetic fibers especially polyamide and polyester and fiber engineering can produce, modify, and tailor fibers in ways far beyond the performance limits of fibers drawn from silkworm cocoon, grown in the fields or spun from the fleece of animals. Polyester fiber has good easy care properties and polyamide fibers have better elastic properties. The yarns are either woven or knitted to develop fabrics. Today's apparel fabric maximizes enjoyment and comfort in indoors as well as outdoors and in any kind of weather. Waterproof, windproof, and breathable through different finishing processes are just a few of many properties in demand. Therefore, stretch properties can be imparted to polyamide fibers using textured nylon in combination with elastane yarns. Certain desired properties can be built into polyester and polyamide fibers during production. However, polyamide seems to be losing its share to polyester, overwhelmed by sheer volume if not performance. Many woven industrial and apparel fabrics seem to favor polyester. Polyamide's dyeability is an advantage, but not sufficiently so to overcome the supply and variants available in polyester.
Photodermatology, Photoimmunology & Photomedicine, 2010
Introduction: Cotton fabrics used in summer do not often provide good protection against solar ul... more Introduction: Cotton fabrics used in summer do not often provide good protection against solar ultraviolet (UV) radiation. Heavy cotton fabrics can provide good protection against UV radiation. However, heavy fabrics are not good from a comfort point of view as the air permeability and moisture vapour transmission rate is very low. Objectives: To engineer cotton fabrics which will provide maximum UV protection without sacrificing the minimum requirement of air permeability and thermal resistance for a particular climatic condition. Methods: Sixteen plain and sixteen twill woven fabrics were manufactured using different cotton yarn count and picks per cm. Nonlinear regression models were developed to relate the fabric parameters with the ultraviolet protection factor (UPF), air permeability and thermal resistance. Optimization problems were formulated for UPF maximization keeping air permeability and thermal resistance as constraints. Optimization problems were solved to find out the values of yarn count and picks per cm. New fabrics were then woven using optimized combinations of yarn count and picks per cm, and error assessment between the target and the achieved fabric properties was performed. Results: The target, optimized and achieved fabric properties are showing good association. When air permeability requirement is high, the engineered cotton fabric can provide good UV protection (UPF 4 15). When the air permeability requirement is low, the engineered cotton fabric can provide excellent UV protection (UPF 4 40). Conclusions: It is possible to engineer cotton fabrics to maximize the UV protection without compromising with the comfort properties.
Textile Research Journal, 2009
A lockstitch is formed by the interlacement of needle and bobbin threads. During high-speed sewin... more A lockstitch is formed by the interlacement of needle and bobbin threads. During high-speed sewing, needle thread is subjected to repeated tensile stresses, heat, bending, pressure, torsion, and wearing. Therefore, the mechanical properties of thread, which become altered during sewing, are very important for its performance and durability. In order to design a sewing machine and threads for maximum strength retention, it is important to understand how the mechanical properties of the thread change as it progresses through the machine and become incorporated into the seam. In this paper, the tensile properties of the needle thread are measured at four sewing stages: before sewing, after dynamic loading at the tension regulator, after passage through the needle and fabric, and after bobbin thread interaction. Mercerized cotton, polyester staple spun, polyester—cotton core spun, and polyester—polyester core spun threads are used and the contribution of dynamic loading, passage through...
Textile Research Journal, 1996
Three POY yarns of 80/100, 80/48, and 80/34 denier/filament are textured with four variables at f... more Three POY yarns of 80/100, 80/48, and 80/34 denier/filament are textured with four variables at five levels. The Box-Hunter statistical experimental design is used to produce thirty-six samples in each case. The effects of texturing variables—draw ratio, disc surface speed to yam speed ratio ( D/Y ratio), first heater temperature and heater contact time on tensile properties, crimp characteristics, dye uptake, broken filaments, and tight spots—are studied. First heater temperature and draw ratio have a significant influence oh tensile, crimp, and dyeing properties. With increased D/Y ratio, broken filaments decrease but tight spots increase. A proper selection of the D/Y ratio gives acceptable levels of broken filaments and tight spots.
Textile Research Journal, 1991
ABSTRACT
Textile Research Journal, 1990
ABSTRACT We describe laundering and wrinkling trials on woven grey and dyed fabrics made from air... more ABSTRACT We describe laundering and wrinkling trials on woven grey and dyed fabrics made from air-jet textured cotton/filament composite yams as weft. The tensile and bursting strength properties of the fabrics are not affected much by the laundering treatments. The textured yarn grey fabrics in general show higher relaxation with laundering, resulting in increased thickness, thermal insulation, and abrasion resistance, and re duced air permeability and tear strength. The greater strain relief due to laundering of the bulkier textured yam structure also helps to improve the crease recovery and wrinkling properties of these fabrics. Fabrics made with textured yams show higher wrinkle recovery than the parent yarn fabrics at various strain levels. The extent of whiteness gain in grey fabrics and color loss in dyed fabrics is almost the same in both the parent and textured yarn fabrics as a consequence of laundering treatments. The textured yarn fabrics, however, show higher color value than those from the parent yarn.
The Journal of The Textile Institute, 1976
Journal of the Textile Institute, 1996
A study to characterize the structure of air-jet textured yarn in terms of its migration paramete... more A study to characterize the structure of air-jet textured yarn in terms of its migration parameters has been carried out by using the tracer fibre technique. An attempt has been made to establish the relationship between the migration parameters and the properties of air-jet textured yarns using polyester (dry and wet textured), nylon (wet textured) and polypropylene (wet textured) yarns.Physical bulk, instability, loop size, loop frequency, tenacity, breaking elongation and initial modulus were measured for various air-jet textured yarns produced using different air pressures. Migration was found to be highest in polyester (wet textured) yarns followed by wet textured polypropylene and nylon yarns. It was observed that physical bulk, loop frequency and initial modulus increases with increasing migration parameters, while tenacity, instability and breaking elongation decreases with migration parameters.Yarns produced from all three materials show similar trends. Bearing in mind the differences in dpf, the polyester feed materials showed relatively higher migration and better properties.