Determination of optimal system parameters to measure bending property of fabric based on the CHES-FY system

The main content of the paper is to determine the optimal system parameters to measure bending property of fabric based on the Comprehensive Handle Evaluation System for Fabric and Yarn (CHES-FY). Four system parameters of the CHES-FY system were selected, including space distance between a pair of jaws, space distance between Bi-U-shaped pins, vertical distance between a pair of jaws and Bi-U-shaped pins, and diameter of Bi-U-shaped pins. In order to both determine the sequence of significant influences of the four system parameters on bending property, and to determine the optimal values of the four parameters to measure bending property of fabric, the Orthogonal design method was adopted to set the four system parameters as four factors and to assign four levels to each factor. Correlations were conducted between bending property and the featured indices (slope and peak value) from the pulling-out force and displacement curves recorded by the CHES-FY system. Comparing results show that the featured indices have good relations with both bending rigidity and bending length measured by FAST-2 meter as well as drape coefficient. Range values and average values are used to assess the significant relation of both factors and factor’s levels with bending property of fabric. The sequence of significant influences of the four system parameters on bending property are diameter of Bi-U-shaped pins, space distance between Bi-U-shaped pins, vertical distance between a pair of jaws and Bi-U-shaped pins, and space distance between a pair of jaws. Moreover, the optimal parameters’ levels are also obtained to better measure bending property of fabric. It indicates that the optimal system parameters of the CHES-FY system are a highly effective combination in evaluating bending property of fabric.     

Effects of parameters on mass index of the CHES-FY system

The main content dealt with in this paper is to discuss effects of parameters (bending rigidity, sample size and sensor resolution) on one featured index measured by the comprehensive handle evaluation system for fabrics and yarns (CHES-FY) system, which is named as mass index utilized to on-line evaluate mass of fabric so as to make quick inspection on evenness of fabric under coating and finishing. Based on the deformation shape of fabric in the weighting step of the CHES-FY system, the mass index was featured from the pulling-out force and distance curve. Comparisons between the mass index measured by the CHES-FY system and mass by electronic balance were conducted. It shows that good correlation exists between theoretical and experimental values. Furthermore, effects of bending property and specimen size as well as sensor resolution were discussed, which indicated that variation of the mass index exhibited quadratic relations with bending rigidity of fabric. Moreover, the mass index’s result could be significantly improved to precisely evaluate mass of fabric by selecting both high resolution of sensor and specimen size in width. It demonstrates that the mass index can be adopted to characterize mass of fabric, and the CHES-FY system can be utilized to have on-line and accurate inspection on mass of fabric.     

Effects of softeners and laundering on the handle of knitted PLA filament fabrics

We have studied the effects of softeners and repeated laundering on the handle of knitted fabrics constructed from poly(lactic acid) (PLA) filament yarns derived from corn-starch. The fabrics were assessed: a) subjectively, via a panel of volunteers, in terms of their perceived softness and ‘scroopiness’; and b) objectively, using a Kawabata Evaluation System for Fabrics (KES-F), in terms of their low-stress mechanical properties. The study employed two fabric variants and a range of commercial softeners in an attempt to determine the combination that would provide optimal handle and durability to laundering. We found the standard KES-F parameters B, 2HB, G, 2HG, and SMD to be generally well-correlated with the subjective assessment of softness and scroopiness. Although repeated laundering reduced somewhat the beneficial effects of the softeners, this deterioration was not severe, and we were able to identify specific formulations that can provide good handle coupled with acceptable durability. The fabric handle was seen to be influenced by the chemical nature of the softening agent, the type of emulsion employed and the degree of hydrophobicity (assessed in terms of wettability); on the other hand, the ionicity of the softener appeared not to play a significant role.     

Measurement and characterization of bending stiffness for fabrics

Aesthetics and handle of end-use textile products mainly depend on bending behaviour, especially for woven and knitted fabrics interlaced by yarns, which necessitates the development of apparatuses that can measure and characterize bending property of yarns and fabrics with the same principle so as to investigate the relationships of bending properties between yarns and fabric. The comprehensive handle evaluation system for yarns and fabrics (CHES-FY) was developed based on multiple properties through single test in principle to measure and characterize weight, bending, friction and tensile properties just by one pulling-out test, whose basic structure and principle of bending step of CHES-FY is just analyzed in present paper. A three-point bending in principle was utilized to model and to describe the bending properties of fabric, and the corresponding formula was obtained for calculating the bending rigidity of sample. The comparisons of bending rigidity based on nineteen fabrics have been conducted by using CHES-FY (both for the yarns and fabrics) and KES-FB2, respectively. The measured results show that there exists high correlations between the two measurement systems for fabrics, and indicates that the approach by using the CHES-FY is feasible and accurate in measuring bending rigidity and characterizing bending behaviour.     

A mathematical model to compare the handle of PLA and PET knitted fabrics after different finishing steps

We have studied a mathematical model to compare the handle of polylactic acid (PLA) and polyethylene terephthalate (PET) fabrics throughout finishing steps. Mechanical and surface properties at low stress of PLA and PET fabrics and the effects of different finishing treatments on these properties are investigated. The KES-FB (Kawabata Evaluation System for Fabrics) is used for the measurements of low stress tensile, shear, bending, compression and surface properties. There is no standard method to determine the total handle value for summer knitted fabrics. Therefore a mathematical method i.e. the Weighted Euclidean Distance method was used to indirect determination of total handle value from the KES-system parameters. The results reveal that the mechanical and surface properties as well as handle of PLA and PET fabrics change significantly after different finishing stages. The difference between handle of PLA and PET fabrics has been significantly reduced after dyeing, drying, heat setting and softening processes.     

Investigation of the effect of continuous finishing on the mechanical properties and the handle of wool fabrics

The effect of scouring, bleaching and dyeing on the low stress mechanical and surface properties of wool woven fabrics was studied. Fabric properties were measured by the KES-FB system. In general, mechanical properties of the treated fabrics are greatly affected by scouring, moderately by dyeing and least by bleaching.     

An investigation of continuous finishing and dyeing on the mechanical properties and handle of cotton fabrics

In this paper, the effect of continuous finishing-desizing, scouring, bleaching and dyeing of woven cotton fabrics on the low stress mechanical and surface properties has been studied. The cotton fabric properties were measured by the famous KES-FB system. The handle of the finished fabrics were calculated by the handle evaluation programme. The results showed that the mechanical properties changed significantly by the desizing and gradually by the scouring, bleaching and dyeing processes.     

Comfort and handle related properties of P/V blended air-jet textured yarn fabrics

The effect of blend percentage on comfort and handle related properties of fabrics made from polyester/viscose blended air-jet textured yarn weft were studied and the results were compared with fabrics made from polyester/viscose ring-spun yarn wefts of similar linear densities. It is observed that with increase in polyester content in the blend, the air permeability and water vapour permeability reduces whereas thermal resistance, transverse wicking and shear rigidity increases both in ring-spun yarn and textured yarn fabrics and bending rigidity increases in textured yarn fabrics. Textured yarn fabrics exhibit lower air permeability and extensibility, higher thermal resistance, relative water vapour permeability, transverse wicking values and bending rigidity as compared to the ring-spun yarn fabrics.     

Physiological signal analyses of frictional sound by structural parameters of warp knitted fabrics

The purpose of this study is to offer acoustical database of warp knitted fabrics by investigating frictional sound properties and physiological responses according to structural parameters such as construction, lap form, and direction of mutual guide bar movement. Fabric sounds of seven warp knitted fabrics are recorded, and Zwicker’s psychoacoustic parameters — loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z) — are calculated. Also, physiological responses evoked by frictional sounds of warp knitted fabrics are measured such as electroencephalogram (EEG), the ratio of high frequency to low frequency (HF/LF), respiration rate (RESP), skin conductance level (SCL), and photoplethysmograph (PPG). In case of constructions, frictional sound of sharkskin having higher loudness(Z) and fluctuation strength(Z) increases RESP. By lap form, open lap has louder and larger fluctuating sound than closed lap, but there aren’t significant difference of physiological responses between open lap and closed lap. In direction of mutual guide bar movement, parallel direction evokes bigger changes of beta wave than counter direction because of its loud, rough, and fluctuating sound. Fluctuation strength(Z) and roughness(Z) are defined as important factors for predicting physiological responses in construction and mutual guide bar movement, respectively.     

The effects of some machine parameters on the spirality in single jersey fabrics

In this work, the effects of machine parameters on the fabric spirality, which is an important quality problem of single jersey knitted fabrics, are investigated. For this aim, two circular knitting machines with the same gauge, but one of them revolving in the reverse direction, are chosen. Single jersey fabric samples with the same weight per square meter and the same yarn count (Ne 20 Cotton) are knitted on the chosen machines at four different numbers of knitting systems. The effects of the number of the knitting systems and the rotation directions of the machines on the spirality angles are investigated.     

Computerized color separation system for printed fabrics by using backward-propagation neural network

Textile production must be coupled with hi-tech assistant system to save cost of labor, material, time. Therefore color quality control is one very important step in any textiles, however excellent the fabric material itself is, if it lacks good color, then it may still result in dull sale. Therefore, this paper proposes a printed fabrics computerized color separation system based on backward-propagation neural network, whose primary function is to separate rich color of printed fabrics pattern so as to reduce time-consuming manual color separation color matching of current players. What it adopted was RGB color space, expressed in red, green, and blue. Analyze color features of printed fabrics, use gene algorithm to find sub-image with same color distribution as original image of printed fabrics yet smaller area, for later color separation algorithm use. In terms of color separation algorithm, this paper relied on supervised backward-propagation neural network to conduct color separation of printed fabrics RGB sub-image, and utilized PANTONE® standard color ticket to do color matching, so as to realize accurate color separation.     

Study the effect of operating parameters and intrinsic features of yarn and fabric on thermal conductivity of stretch knitted fabrics using artificial intelligence system

An artificial intelligence-based system approach is presented in which the effects of the operating parameters and intrinsic features of yarn and fabric on Thermal Conductivity of Stretch Knitted Fabrics are investigated. These parameters were pre-selected according to their possible influence on the outputs which were the thermal conductivity. An original fuzzy logic based method was proposed to select the most relevant parameters. The results show that Knitted Structure’s is the most important input parameter, followed by Lycra Proportion (%), Loop length (cm), Yarn Count, Weight per Unit Area (g/m²), Thickness (m), Gauge, Lycra Yarn Count (dtex) and Yarn Composition. According to our previous works, two types of model have been set up by utilizing multilayer feed forward neural networks, which take into account the generality and the specificity of the product families respectively. The relative importance of the input variables was calculated using the connection weight approach. The results were found to agree with the fuzzy logic based sensitivity criterion. The trend analysis of the developed model revealed the influence of various input parameters on the thermal conductivity of knitted fabrics. Thus, it is believed that artificial intelligence System could efficiently be applied to the knit industry to understand, evaluate and predict thermal comfort parameters of stretch knitted fabrics.     

Assessing the relationship among fabric constructional parameters, fractional reflectances and cover factors of polyester fabrics by experimental and mathematical methods

This paper focuses on the assessment of the relation among constructional properties, fractional reflectances and cover factors of fabrics woven from polyester yarns. A novel equation for the calculation of the relation between fractional reflectance and fabric cover factor was proposed and the usage of the equation was assessed by reflectance measurements. 48 polyester fabrics having different constructional parameters were used and the fabrics differed from each other by their cover factors. The warp yarn type and count, warp density and warp yarn twist were the same but weft yarn count, weft yarn fiber count and weft density were different for the fabrics in the experimental sub-groups. The reflectance measurements were conducted on the pretreated but undyed fabric samples as well as on the individual yarn systems of the same fabrics. Fabrics with the same cover factors exhibited different fractional reflectances. Reflectances were found to be dependent on the cover factor as well as on yarn fiber fineness, yarn count, yarn density and fabric weave. The changes in crimp of the yarns according to different construction parameters also governed the changes in fractional reflectances of fabric surfaces. The proposed equation was tested according to different fabric construction parameters and it was concluded that fiber fineness and weave pattern were among the most important parameters which govern the total light reflectances from the fabric surfaces, although they are not incorporated in the calculation of the fabric cover factors. The proposed equation was used to explain the effects of these components on the reflectance behavior of the fabric surfaces and on fabric cover.     

An investigation in structural parameters of needle-punched nonwoven fabrics on their thermal insulation property

The thermal characteristics of hollow polyester fibers were compared with solid polyester fibers in order to study their processing behavior and performance characteristics. The effects of different processing and structural properties including fiber diameter, bulk density of layer, and surface pressure on layers of needle-punched nonwoven fabrics with hollow fibers on thermal resistance properties were also investigated. The results show that hollow fibers have a higher thermal resistance in comparison with solid ones. This is a consequence of air trapping inside the fibers, higher bulkiness, and higher surface area of hollow fibers. Furthermore, thermal resistance of microfibers is better than those of macrofibers in both hollow and solid fibers. The thermal resistance of nonwoven subjected to this study, have an inverted-U-shaped pattern versus the bulk density of the fabric. The results also showed that thermal resistance of needle-punched nonwoven fabrics can be affected by the range of heater temperature during the test, however considerably can be affected by fabric thickness as a main structural property of nonwoven fabrics.     

Prediction models for audible distance using mechanical and psychoacoustic parameters of combat uniform fabrics

A short audible distance for the rustling sound of combat uniform fabric helps to reduce soldiers’ exposure to the enemy forces. The objectives of this study were to evaluate mechanical properties and sound characteristics of combat uniform fabrics, to investigate their influence on audible distance at which fabric’s rustling sound can be reached to human ear, and to establish prediction models for audible distance using mechanical and psychoacoustic parameters. Six types of combat uniform fabrics were used as test specimen. Mechanical properties of the specimens were measured according to the KES-FB system and the acoustic characteristics of the fabrics were analyzed by the Sound Quality System. Audible distances of the fabric sounds were assessed by 30 male soldiers. The audible distances were determined by the distance of which the participants walked away from a starting point in a straight line until they could not hear the sound. Water repellent finished fabric (W-WR), which showed the highest values of bending rigidity, shear stiffness, sound pressure level, loudness(Z) and sharpness(Z) among all fabrics, had the longist audible distance. Fabric for summer season (W-S) had the shortest audible distance in all frictional speed levels, which indicates the best auditory camouflage performance. Coefficient of friction was chosen as the variable affecting loudness(Z) of fabric sounds. Loudness(Z) was finally chosen as the prediction parameter for the audible distance by path analysis.     

Objective wrinkle evaluation system of fabrics based on 2D FFT

Drying is one of the main processes in the course of washing laundry. During the washing and drying processes in an electric or gas dryer, wrinkles can form on garments. To minimize the wrinkles on the clothes after the processes, a reliable and objective method of assessment of wrinkles should be devised. Wrinkles have been assessed with visual inspection methods by human observers, which were defined by AHAM or AATCC. This method cannot provide objective data for wrinkles because people judge the same things differently according to their own subjective criteria. Thus, this paper is focused on the development of an objective and quantitative system for grading fabric wrinkles based on the 2D-FFT. The system developed in this study has been proven to be objective and quantitative in comparison with the existing test methods.     

Surface modification of polyester fabrics by enzyme treatment

In this study, the effect of enzymatic hydrolysis using lipase and cutinase on poly(ethyleneterephthalate) (PET) fabrics was investigated in an attempt to improve the hydrophilicity of these fabrics. The hydrolytic activity of the enzymes was expressed for variations in pH levels, temperatures, enzyme concentrations, and treatment times. The effects of using a nonionic surfactant were examined by measuring moisture regain and surface wettability. Finally, the fabric characteristics that were affected by enzyme treatment were evaluated by tensile strength and scanning electron microscopy. The optimal treatment conditions for lipase were determined to be a pH of 4.2, a temperature of 50 °C, a lipase concentration of 100 %, and a treatment time of 90 min; those for cutinase were determined to be a pH of 9.0, a temperature of 50 °C, a cutinase concentration of 100 %, and a treatment time of 60 min. At optimal enzymatic treatment conditions, we got the significant results of increase on the moisture regain and the water contact angle (WCA) and water absorbency effectively decreased. Triton X-100 facilitated cutinase hydrolysis on PET fabrics; however, it was ineffective for lipase. With enzymatic treatment, the tensile strength did not decrease.     

A novel method to analyze the moisture liberation of textile fabrics

In this paper, a purpose-built apparatus was used to analyze the moisture liberation of textile fabrics. Fabrics were wetted and placed in an air-conditioned room to test the variation of weight and surface temperature during the process of moisture liberation. Effects of textile materials and fabric structures on the velocities of moisture liberation of fabrics were analyzed; the temperature variation and its relationship with moisture regains of fabrics in the moisture liberation were also studied. Moisture liberation velocities of polyester and silk fabrics are much higher than that of wool and cotton fabrics. For the same textile materials, knitted fabrics absorbed more water and thus took longer time to liberate the water. The surface temperature of fabrics showed three stages during moisture liberation. With the decrease of moisture regain, fabric temperature decreased gradually and jumped quickly to ambient temperature. In this way we could evaluate the moisture desorption of fabrics and develop quick-drying fabrics with imporved moisture and thermal properties.     

Optimization of enzymatic treatment of polyamide fabrics by bromelain

In this study, we investigated the effects of enzymatic hydrolysis on polyamide fabrics by using bromelain as an enzyme. The hydrolytic activity of bromelain was evaluated on the basis of the number of carboxylic groups formed on the surface of the polyamide fabrics, and it was measured using the reactive dye absorbance. In addition, 2,4,6-trinitrobenzenesulfonic acid was added as an indicator to measure the number of amino groups released into the treatment liquid by the changes in color of the liquid. The optimum treatment conditions were bromelain pH of 6.0, treatment time of 120 min, temperature of 50 °C, concentration of 10 % (owf), and L-cysteine concentration of 70 mM. The weight loss in the fabric after treatment with bromelain facilitated by L-cysteine significantly improved; however, the tensile strengths of the polyamide fabrics did not show any differences. Bromelain hydrolysis of the polyamide fabrics thus improved hydrophilicity without damaging the fabrics’ strength.     

Electrophotographic printing of fabrics: Investigating the effect of fabrics on color reproduction

Fabric printing systems are essentially needed nowadays and should meet the requirements of manufacturers. Digital electrophotographic (Xerographic) printing has the potential of meeting these requirements. Digital electrophotography printing is affected by several parameters, including printer and substrate type which determine the final printed color gamut and the quality of reproduction. To examine these effects, we performed different tests on a number of printed common fabrics. The gamut volume was generated by Eye-One spectrophotometer, ProfileMaker, and ColorThink software. The results indicated that all fabrics cannot be printed with electrophotography. Also, the gamut volume of the printed fabrics was low. Properties of different types of fabric were investigated by the Fourier transform infrared spectroscopy, scanning electron microscopy, spectrophotometer, and fabrics-specific tests (fastness).