D. Raja

Comparison of different methods to measure the transverse wicking behaviour of fabrics

In this article, three test methods are described to measure the water spreading behaviour of textiles such as rate of absorbency and total absorbent capacity. The methods described are manual method, commercial image analysis method using Photoshop and embedded image analysis method using digital signal processor through MATLAB software (EIAS). With these methods the rate of absorbency and total water absorbent capacity were analysed in 12 different knitted/woven fabrics. In order to compare the three test methods, the correlation among the methods were analysed. A very good correlation (more than 0.9) was found between the manual water spreading tests and commercial image analysis method using Photoshop when compared to manual versus EIAS method. Also Photoshop versus EIAS method correlation was found better than manual versus EIAS method.

A dynamic sweat transfer tester for analyzing transverse sweat transfer properties of multi-weave structure fabrics

The dynamic sweat transfer tester for analyzing the sweat transfer behavior of multi-weave structure fabrics (single fabric contains different weave structures) has been designed and developed. This instrument has been developed to evaluate the sweat transfer rate in 16 different directions and 48 different regions for a test specimen of 7 cm diameter. The concept of the sweat measurement is to measure the sweat transport time required to reach the unit area of the fabric. The instrument works under the principle of electrical conductivity, that is, wetted cotton fabric acts as an electrical conductor between the power connected (5 V) copper pins and ground connected copper pins. The unique feature of this instrument is that the sweat transfer rate can be measured in fabrics which have irregular spreading behavior (single fabric that has different weave structures) at one step. Twelve different woven fabrics have been analyzed for the sweat transfer behavior using the instrument, and the results were well correlated (R2 = 0.925) with manual test method.

Effect of cyclic stress on the transverse wicking behaviour of cotton/lycra knitted fabrics

It is extremely important to evaluate transverse wicking behaviour of elastic knitted fabric while the fabric simulated in different body motions. In this paper, the effects of short interval dynamic extension and recovery on fabric transverse wicking behaviour were evaluated as the samples were subjected to different rate of extension (speed), different percentage of cyclic extension and different liquid flow rate. For this application, a new cyclic stress instrument was designed and developed to apply repeated dynamic extension and recovery on the fabric. The developed instrument is operated through embedded micro controller programme. The effect of speed, percentage of cyclic extension and flow rate with respect to the dynamic transverse wicking behaviour of elastic knitted fabric has been studied using Box–Behnken experiment model. The experiment model identifies the principal experimental variables such as flow rate, percentage of cyclic extension which has the greatest effect on the transverse wicking behaviour of elastic knitted fabric.

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.

Influence of blend ratio and linear density on liquid spreading characteristics of bamboo/ cotton-blended yarn knitted fabrics measured by liquid spread tester

In this study, a new liquid spread tester, designed and developed in an earlier work by the authors, has been used for the study and analysis of the transverse wicking characteristics of single jersey-knitted fabric produced from bamboo/cotton-blended yarn. The most significant liquid spreading characteristic, namely the liquid spreading rate, has been measured and analysed for two sets of the knitted fabric composed of bamboo/cotton yarn, one of linear density Ne 20s and the other of Ne 40s yarn. The yarn blend composition was varied in a similar manner for both sets of fabric. It was observed that liquid spreading rate decreased with increase in bamboo content for all the blend proportions investigated. It was also found that this property is higher in the wale-way direction than the course-way direction.

Investigation on wicking behavior of the knitted fabrics under different deformation state

Abstract Many researches have been carried out to analyze the wicking behavior of the knitted fabric based on different principles. In this study, an investigation on wicking behavior of knitted fabrics under different deformation condition is attempted. An instrument has been designed and developed to measure the wicking rate of the fabric based on the principle of image processing technique under dynamic states with respect to time by simulating different movements. This instrument has been aimed to quantify the rate of wicking under different deformations in required time intervals and also the pattern of wicking area on both sides of fabric simultaneously. The statistical result shows that wicking in fabric under dynamic condition has been increased significantly on the knitted fabrics than the static condition. The comparative study of wicking trend at the front and back has been carried out and shows that the area of wicking is higher in front than back side of the fabric at any given period of time. The result shows that wicking in fabric under dynamic condition has been increased significantly on all the knitted fabric. The developed novel instrument could be utilized to carry out the study of the wicking behavior of any kind of fabrics matching to the real situation with higher accuracy and precision.