For all material types, the tenacity and elongation (%) values of compact yarns were higher than those of the conven- tional ring yarns. But the evaluations of statistical analysis results of the differ- ence of two systems changed according to the types of material. When we examined yarn tenacity, there was an important difference between compact and conventional ring yarns which were produced with 100% wool for two yarn counts and all twist levels. The compact-spun yarns’ tenacity and elongation (%) values are higher than the conventional ones, but at the high twist level, the elongation values of compact and conventional ring yarns were very similar. On the other hand, when we examined 45% wool/55% PET yarns, the differ- ences of tenacity values were found to be statistically significant only for 25 tex yarns (Figure 4). In addition, there was no statistically significant difference between the compact and conventional ring yarns which were produced with 45% wool/50% PET for elongation (%) values, and those for both yarn counts.

 There was a statistically significant dif- ference between the compact and con- ventional ring yarns produced with 50% wool/50% PAN in terms of yarn tenacity for both yarn counts, 25 tex and 36 tex. However, the differences in the two spin- ning systems were found to be significant in terms of elongation (%) values for 25 tex yarns only. When we examined 100% PAN yarns, there were statistically significant dif- ferences between the two spinning sys- tems for low twist levels only in terms of tenacity and elongation at break (%) (Figure 5). Yarn hairiness When we examined yarn hairiness val- ues, the compact yarns’ hairiness values were very low, even for yarns with low twist levels for all material types. For example in 36 tex yarns produced with 50%wool/50% PAN, the compact yarns’ S3 values were found as 1115 for ? tex =2530, and 769 for ? tex =3160. On the other hand, the classic yarns’ S3 val- ues were found as 2563 for ? tex =2530, and 1643 for ? tex =3160. According to statistical analyses, statistically sig- nificant differences were found between compact and conventional ring yarns for all material types in terms of Uster hairi- ness and Zweigle hairiness.

 The hairiness properties of yarns were measured using a Zweigle G565 hairiness tester which classifies hair length on yarn surfaces. The hairiness measurementss- how that there is a significant reduction in all hair length classes on the compact yarn’s surface. This improvement was found to be promising for the compact yarn’s subsequent textile processes. For example, knitting yarns are generally spun with low twist values which pro- vide softer and hairier yarn. Although high hairiness of a yarn is accepted as an advantage for some knitting yarns, it is also a disadvantage because it is a source of pilling. The S3 code, which defines

the total number of hairs of 3mm length and above, exhibits a hairiness level that causes the pilling problem. When compact and conventional yarns are compared, it is seen that compact yarns have lower S3 values than conventional ring yarns (Figure 6). In addition, yarn hairiness is very important for the weav- ing preparation and process, so compact weaving yarns have more advantages than conventional ring yarns in terms of yarn hairiness and yarn strength. According to these results, although the compact yarns are produced with low twist levels, their yarn hairiness values are lower than the conventional ring yarns. So we can produce softer products with compact yarns when we compare them with conventional ring yarns. In addition, low twist level means high production. n Summary In this experimental work, some of the yarn properties of compact spun and conventional ring spun yarns were compared. We investigated the effects of spinning technique and material type on the properties of yarn. The compact yarns covered in this study showed better yarn properties than con- ventional ring yarns. It has been demon- strated that there are statistically signifi- cant differences for the significance level of ?=0.05 between all the yarn properties of 100% wool compact and conventional ring yarns.

 In terms of other yarns spun with 45% wool/50% PET, 50% wool/ 50% PAN and 100% PAN raw materi- als, these differences have not been found statistically significant for all yarn parameters. 100% wool compact yarns have better tenacity, elongation at break (%), evenness, thinand thick places, nep values and hairiness values than conven- tional ring yarns. But only 50% wool/ 50% PAN compact yarns have better tenacity and lower yarn evenness (Uster CV%) values than conventional ring yarns, and their differences were found to be statistically significant for ?=0.05. In 100% PAN yarns, the difference of Uster CV% and I.P.I. values between two spinning systems were not found to be statistically significant for ?=0.05. According to these results, the difference of yarn parameters between two spinning systems is clearer when natural fibres are used. In addition, the difference is clearer when a high percentage of natural fibre is used in the blend, also. Another comparison was made between two yarn counts, and it was seen that there was also a significant difference between the two different yarn numbers.

In the fine yarn counts, the number of fibres in the yarn cross-section is more important than the coarser yarn counts, because fine yarn has fewer fibres than coarser yarn in the yarn cross-section. In compact spinning, the drafted fibres emerging from the nip line of the drafting arrangement’s front roller are condensed in a line. In this way, almost all the drafted fibres are incorporated into the yarn body. Thus, fine compact yarns have more advantages than fine conventional ring yarns. In addition, the compact yarns at low twist level have better yarn properties values than conventional yarns at high twist level. For example, in 25 tex yarns produced with 50% wool/50% PAN, con- ventional ring yarn tenacity values were 8.25 cN/tex for ? tex =1675, and 9.81 cN/ tex for ? tex =2055. On the other hand, the compact yarn tenacity value was 9.80 cN/tex for ? tex =1675. However, the most important advantage of the compact spinning technique is the reduction in yarn hairiness. When we looked at the laboratory results for all material types, the compact spun yarns have less yarn hairiness than the conven- tional ring-spun yarns. This reduction in yarn hairiness brings new opportunities for producing different products in the future. Weaving and knitting sectors can profit from the compact spinning system. n Conclusions § Fine compact yarns have more ad- vantages than fine conventional ring yarns. § The most important advantage of the compact spinning technique is a reduction in yarn hairiness, which brings new opportunities for the production of different products in the future. The weaving and knitting branches can profit from the compact spinning system. § Although the compact spinning tech- nique brings advantages regarding quality and production, we must bear in mind that the investment cost of the compact spinning machines are higher than the conventional ring spinning machines, and the cost of compact yarn is higher than the con- ventional ones, also. Consequently, worsted compact yarns are preferred for high quality and expensive prod- ucts, especially for woven fabrics in the market.