Comparison of the results of different hairiness testers for cotton-tencel blended ring, compact and vortex yarns a

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1 Indian Journal of Fibre & Textile Research Vol. 39, March 204, pp Comparison of the results of different hairiness testers for cottontencel blended ring, compact and vortex yarns a Musa Kilic b & Ayşe Okur Department of Textile Engineering, Dokuz Eylül University, Buca, Izmir, Turkey Received 26 March 203; revised received and accepted 4 June 203 Hairiness results of Zweigle, Uster Zweigle Hairiness Tester 5 () and Uster Tester 5 S800 () have been compared for ring, compact and vortex yarns. For this purpose, 00% cotton, cottontencel LF (67:33, 50:50 and 33:67) and 00% Tencel LF yarns have been produced from each spinning system. In general, correlations between the results of Zweigle and devices, working with the same measuring principle, are found statistically significant at 99% confidence level for all spinning systems. However, the correlations between the results of against Zweigle or are also found statistically significant at 95% confidence level for all spinning systems. But, for vortex yarns, negative correlation coefficients are detected between the results of against Zweigle or in terms of blend ratio. This situation could be the result of wrapped structure of the vortex yarn and different measuring principles of the hairiness testers. Keywords: Compact yarn, Hairiness, Ring yarn, Tencel yarn, Vortex yarn Introduction In addition to the traditional yarn parameters such as unevenness, imperfections, strength and elongation, the hairiness also plays an important role in evaluation of the yarn quality. Hairiness influences the performance of many processes like weaving, knitting or dyeing as well as the handle, appearance and end use of the final fabric or garment. Because the hairiness is an important parameter for yarn quality, it must be measured accurately and precisely. Measurement of hairiness has been dealt for almost fifty years and many hairiness testers with various measuring methods have been developed. Although many of these measuring systems have become commercial, the results of these systems are not easily comparable, because the results are expressed in different units for almost each different system. In this study, it was aimed to analyze the results of different hairiness testers for the yarns produced by different spinning systems. For this purpose, cottontencel LF blended ring, compact and vortex yarns were used and results were analyzed by correlation analysis. It is seen that many researchers have dealt with the comparison of the results of different hairiness a Presented at the st International Congress of Innovative Textiles, Istanbul, Turkey, 2022 October 20. b Corresponding author. musa.kilic@deu.edu.tr testers. Barella and Manich 2 compared the results of different hairiness testers. They used three different instruments to measure the same yarn series: Digital ITQT hairiness tester, Shirley hairiness meter, and Zweigle G565 instrument. The hairiness parameters compared were the length index (L) for the digital apparatus, the number of hairs protruding more than 3 mm/m (Sh) for the Shirley instrument, and two parameters from the Zweigle G565 apparatus [Pm (hairs protruding more than mm/m ) and (hairs protruding more than 3 mm/m)]. The study showed that there was a reasonable agreement between the results furnished by the three instruments tested. Coll and Marcelo 3 compared the Zweigle G565 and Uster Tester 3 devices. They observed that the spinning parameters studied influence the yam hairiness for all index, but not in a similar way. A high correlation was obtained between the two exploration methods for combed yams and not so good for carded cotton yarns. The formation of fuss depends on the material preparation. Appasamy and Narasimham 4 used statistical methods for comparing the performance of different testers, including ANOVA to divide the total variance into four components namely the count effect, the instrument effect, the interaction, and the inherent natural variation. Tyagi 5 investigated the relationships between the hairiness values of Uster Tester 3 and Zweigle G565 for viscose OE rotorspun yarns.

2 50 INDIAN J FIBRE TEXT. RES., MARCH 204 Author indicated that the instrumental readings recorded by Uster Tester 3 and Zweigle hairiness meter did not show direct distinct statistical relationship. This situation was explained by the fact that the measuring methods were fundamentally different. Kothari et. al. 6 analyzed the relationships between the results of hairiness testers which have different measuring principles such as EIBMTH hairiness tester, Shirley hairiness tester, Laserspot and Uster Tester 3. The effect of blend ratio and winding on hairiness properties of ringspun yarns was also assessed. In the study, cottonpolyester blended ring yarns of 30 Ne count with 0:00, 33:67, 50:50, 67:33 and 00:0 blend ratios were used. The results showed that there was a good correlation between the data obtained from all the measuring instruments. Another result of the study was about the effect of blend ratio on yarn hairiness. It was observed that hairiness values of 00% cotton yarn was the maximum, 00% polyester yarn was the minimum and blended yarns were intermediate. Alay and Göktepe 7 investigated the correlation between the hairiness results of Uster Tester 4 and Zweigle. It was aimed to estimate the hairiness level of the same yarn at other hairiness instruments by considering the hairiness value obtained from any hairiness instrument. For this purpose, the correlations between the Zweigle () and Uster Tester 4 (H) instruments were analyzed. Results showed that there was no linear relationship between the hairiness results of Zweigle and Uster Tester 4 for combed ring yarns while there is a good correlation for OErotor spun yarns. Aim of this study is to analyze the results of different hairiness testers for the yarns produced by different spinning systems. Since the results of different hairiness testers are expressed in different units, it is hoped that this study will give a sight to understand the relationships between them in terms of ring, compact and vortex yarns. 2 Materials and Methods In the study, 00% cotton, 00% Tencel LF and 67:33, 50:50, 33:67 cottontencel LF blended combed ring, compact and vortex yarns were used to compare the results of different hairiness testers. All the blends were made in the sliver form. All the yarn types were produced with a linear density of 20 tex. Properties of Tencel LF and the HVI results of Indian St rollergin cotton fibres are given in Table. Twist multiplier was α = 35.4 T/cm. tex for ring tex and compact yarns. Corresponding twist level was set for vortex yarns by considering the Murata s machine catalogue. Yarns were produced on three different spinning systems with five blend ratios. Hence, fifteen types of yarns each containing twelve bobbins/packages were measured by three different hairiness testers. In this study, hairiness of cottontencel LF blended ring, compact and vortex yarns was measured by Zweigle, Uster Zweigle Hairiness Tester 5 () and Uster Tester 5 S800 (). The hairiness measuring system according to measures the entire length of protruding hairs per centimeters of yarn length, whereas the hairiness measuring systems according to Zweigle and measure the number of protruding fibres at various distances from the yarn body. The hairiness value of the is called H, whereas the hairiness values of the Zweigle and is called. The value is the sum of all fibres of 3 mm and longer (cumulative). and use laser transmitters in their measuring units. Laser transmitter scatters constant parallel light beam. On the other hand, Zweigle G 566 uses optical light beam ( S800 and application handbooks). This study compares the hairiness results of different hairiness testers using different measuring principles and units. In the study, H values of cotton Tencel LF blended yarns were measured by with 400 m/min test speed and 2.5 min test duration. Nevertheless, values of yarns were measured by Zweigle and with 50 m/min test speed and 4 min test duration. 3 Results and Discussion Hairiness results obtained from Zweigle, and devices for cottontencel LF blended ring, compact and vortex yarns are given in Table 2. Table Properties of Indian St cotton and Tencel LF 8,9 Indian St Cotton Tencel LF Parameter Value Parameter Value Micronaire 4.2 Titer, dtex.3 Length, mm 3.7 Cut length, mm 38 Tenacity, cn/tex 44.4 Tenacity, cn/tex 37 Elongation, % 3.8 Elongation, % 3 Rd 79.6 Tenacity in wet state, cn/tex 30 +b 8.3 Elongation in wet state, % 5 Color grade 22

3 KILIC & OKUR : DIFFERENT HAIRINESS TESTERS FOR COTTONTENCEL BLENDED YARNS 5 Yarn Zweigle The heavier fibres have a tendency to move out to the periphery of the yarn to form hairs. This may be due to the higher centrifugal forces acting on the heavier fibres that cause them to move out for a greater length and also tend to protrude more. On the other hand, Barella indicated that cotton yarns are known to be less hairy than yarns spun from manmade fibres against long odds. A possible reason for this could be the profiles of the two fibres. Because of the taper structure, the heavier root part of the cotton fibre tends to come out as a protruding end. Nevertheless, both ends have an equal probability of showing up as protruding ends for manmade fibres. This could be one of the reasons for greater hairiness in yarns spun from manmade fibres. The second reason for more hairy structure of manmade fibre yarns could be the slippage forces between the fibres. Tanaka 0,, working with rayonstaple spun yarns, stated that the resistance of fibres to slippage out of yarns has an important role on hairiness. He investigated the relationships between this slippage force and the geometrical structure of yarns, and it was stated that there is a high correlation with the experimental results obtained on the generation of hairiness. Wang et. al. 2, also pointed out that cohesion between the fibres is very important on hairiness. As the cohesion forces between the fibres increase, hairiness decreases as well. Because of the reasons explained above, the hairiness of cottontencel LF blended yarns is expected to increase with the increase in regenerated cellulosic fibre content in the yarn structure. When a general evaluation is made in terms of ringspun yarns, results show that the effect of blend ratio is statistically significant on the results of three hairiness testers. Nevertheless, increasing ratio of regenerated cellulosic fibre content does not result in an exact increasing tendency on the hairiness values (Fig. ). Table 2 Hairiness results of yarns Ring Compact Vortex H Zweigle H Zweigle 00% Cotton :33 CottonTencel LF :50 CottonTencel LF :67 CottonTencel LF % Tencel LF H If the results of compact yarns are evaluated, it is seen that the effect of blend ratio is also statistically significant on the results of three hairiness testers. Furthermore, in literature, 0, also, it is found that the hairiness of 00% cotton yarn is the lowest, 00% Tencel LF yarn is the highest and blended yarns are in between for the three hairiness testers (Fig. 2). ANOVA analysis indicate that blend ratio is statistically significant also for vortex yarns. However, the results show that H values increase but values decrease with the increase in regenerated cellulosic fibre content in the yarn structure (Fig. 3). The possible reasons for this could be mainly the structure of vortex yarns and the difference between the measuring principles of Zweigle / and devices. As it is known, wrapper fibres mainly cause the hairiness in vortex yarns 3, 4. The increase in H value with the increase in regenerated cellulose fibre content in yarn structure could be explained by the increasing mean fibre length and the increasing total length of protruding wrapper fibres, depending on the decreasing cohesion forces. In addition, S+2 value (the total amount of the fibres shorter than 3 mm) also increases with the increasing ratio of regenerated cellulosic fibre content. So that, S+2 value also contributes to the increase in H value. However, this value is not included for the calculation of value. The possible reasons for the decrease of value depending on the increase of the regenerated cellulose fibre ratio in yarn structure could be the measuring principles of Zweigle and. These devices count only the lengths of the fibres perpendicular to the yarn axis. For vortex yarns, many of the protruding wrapper fibres longer than 3 mm might be ignored because of the air vortex effect which inclines them to the yarn axis. Also, this effect becomes greater depending on the increase of the mean fibre length with the increase of regenerated cellulose fibre ratio.

4 52 INDIAN J FIBRE TEXT. RES., MARCH 204 Fig. Hairiness results of ring yarns Fig. 2 Hairiness results of compact yarns In this study, crosssections of the yarns produced in three different spinning systems were also examined to evaluate the fibre distributions in yarn structure. For this purpose, Leica RM 225 rotary microtome were used to prepare the crosssections. In the crosssections of cottontencel LF blended ring yarns, it is observed that Tencel LF fibres migrate towards the outer layers of the yarn to form hairs (Fig. 4), 0,. Crosssection of 50:50 cottontencel LF blended compact yarn is shown in Fig. 4. Tencel LF fibres are shown near the periphery and most of the hairs are formed by these fibres. For 50:50 cottontencel LF blended vortex yarn, Tencel LF Fig. 3 Hairiness results of vortex yarns fibres are located near the periphery of the yarn and form wrapper fibres which are inclined to the yarn body with the air vortex effect. In the study, comparison of the hairiness results of Zweigle, and devices was carried out by correlation analysis for cottontencel LF blended ring, compact and vortex yarns. Results of the analysis are shown as a correlation matrix in Table 3. A general assessment of the measuring principles of three hairiness testers shows that Zweigle and use the same measuring principle. The hairiness measuring systems Zweigle and

5 KILIC & OKUR : DIFFERENT HAIRINESS TESTERS FOR COTTONTENCEL BLENDED YARNS 53 Parameter Pearson Correlation Coe. Sig. (2tailed) N Pearson Correlation Coe. Sig. (2tailed) N Pearson Correlation Coe. Sig. (2tailed) N * Significant at 0.05 level (2tailed). ** Significant at 0.0 level (2tailed). Fig. 4 Crosssections of 50:50 cottontencel LF ring, compact and vortex yarns Table 3 Correlation analysis results for ring, compact and vortex yarns are based on the measurement of the number of protruding fibres at various distances from the yarn body. On the other hand, measures the entire length of single fibres protruding per cm of yarn length. Table 3 shows that correlation coefficients between the results of Zweigle and devices, which use the same measuring principle, are statistically significant at 99% confidence level for ring, compact and vortex yarns. However, Table 2 shows that values of these two testers are quite different; values obtained from Zweigle is greater than. Most reasonable explanation of this situation could be the light sources of two devices. As it is known, Zweigle uses LED light source, whereas uses laser light source which gives more accurate and stable parallel light beam. When the relationships between the and the Zweigle or are studied, it is observed that although the correlation coefficients between the results of and Zweigle or are not Ring Compact Vortex ** 0.29 * ** * * * ** ** ** 0.2 * ** * ** ** 0.62 ** * ** *.0 as high as the correlation coefficients between the results of Zweigle and, they are also found statistically significant at least at 95% confidence level for three spinning systems. But, for vortex yarns, negative correlation coefficients exist between results of and Zweigle or, because of the reasons explained above for Fig. 3. However, it must be considered that test speed is also an important factor on yarn hairiness. As Wang 58 stated, test speed affects yarn hairiness results even with the same instrument. The instruments used in this study operate at different speeds such as 50 m/min (Zweigle and ) vs. 400 m/min (). The test speed effect may come into play, in addition to the other differences discussed above. 4 Conclusion The effect of blend ratio is found statistically significant on the results of three hairiness testers

6 54 INDIAN J FIBRE TEXT. RES., MARCH 204 for all spinning systems. It is observed that the hairiness of 00% cotton yarn is the lowest, 00% Tencel LF yarn is the highest and that the blended yarns is in between for three hairiness testers. On the other hand, for vortex yarns, values decrease and H values increase with the increase in regenerated cellulosic fibre content in yarn structure. The possible reasons for this situation could be the structure of vortex yarns and the difference between the measuring principles of Zweigle, and devices. When hairiness testers are evaluated, it is observed that correlations between the results of Zweigle and devices, which use the same measuring principle, are statistically significant at 99% confidence level for ring, compact and vortex yarns. Nevertheless, the correlations between the results of and Zweigle or are also found statistically significant at least at 95% confidence level. But, for vortex yarns, negative correlation coefficients are found between the results of and Zweigle or, significant at least at 95% confidence level. In conclusion, results of different hairiness testers must be analyzed carefully to evaluate the hairiness of the yarn. The results may vary according to the spinning technology especially for blended yarns. Before making an assessment about the hairiness of a yarn, both the formation of the yarn structure depending on the spinning technology and the measuring principle of the hairiness device must be taken into consideration. Acknowledgement Authors are thankful to Dokuz Eylül University (Project No: 2008.KB.FEN.05) and TÜBĐTAK 22 for providing National Doctorate Scholarship Program. Thanks are also due to Mr. Nevzat Seyok (KARSU Tekstil Sanayi ve Ticaret A.Ş.) for producing the yarns and Mr. Ahmet Duygal (KĐPAŞ Holding) for carrying out the S800 measurements. References Barella A, Text Prog, 3() (983). 2 Barella A & Manich A M, Text Res J, (989) Coll L & Marcelo F X, Boletin Intexte, 02 (992) Appasamy N R V & Narasimham T, ATIRA Commun on Text, 27(3) (993) Tyagi G K, Indian J Fibre Text Res, 29 (2004) Kothari V K, Ishtiaque S M & Ogale V G, Indian J Fibre Text Res, 29 (2004) Alay S & Göktepe F, Tekstil ve Konfeksiyon, 8() (2008) accessed on ). 9 Kilic M & Okur A, Text Res J, 8 (20) Tanaka K, J Text Mach Soc Japan (Eng edn), 2 (966) 47. Tanaka K, J Text Mach Soc Japan (Eng edn), 3 (967) 8. 2 Wang X, Chang L & McGregor B, Text Res J, 76 (2006) Chasmawala R J, Hansen S M & Jayaraman S, Text Res J, (990) 6. 4 Basal G & Oxenham W, AUTEX Res J, 3(3) (2003) Wang X, J Text Inst, 89() (998) Wang X, J Text Inst, 89(2) (998) Wang X, J Text Inst, 88(2), (997) Xia Z, Wang X, Ye W, Xu W & Eltahir H A, Fibers Polym, 2(4) (20) 534.