Karapinar and Erdem (2003) reported that the rapid development in the textile industry has also caused some of the physical properties of cotton fibers to become more important. It could be stated that the following main factors affect the yarn properties: Fiber properties, and Process parameters: yarn count and yarn twist; blend ratio (1st fibre/2nd fiber); re-used waste fibers; waste that is removed (short fiber ratio), preparation processes: machinery (types and adjustments); spinning systems (types and adjustments)

According to the international cotton yarn classification, both Long Staple and Extra-Long Staple Egyptian cottons fall in the category of Extra-Fine count, i.e. that group of cottons that could be spun into yarn count of 45s and higher. Mohamed et al (2005) reported that the major problem and challenge facing the Egyptian cotton textile industry is that Egyptian cotton has two distinct markets: the international market for producing fine and extra fine yarns and the domestic market for producing mainly coarse and medium count yarns.

The textile industry in Egypt needs cheaper cotton to cover the demand of the domestic market i.e. coarse and medium yarn counts. So, there is a cotton gab especially MLS cottons in this respect, the Textile Industries Holding Company in Egypt supply Greek and Sudanese MLS cottons to close this gab to produce coarse and medium counts for local consumptions. Furthermore, the produced and exported yarn count level in the Egyptian spinning mills is around 28.5s, as much as 10-15 percent higher or lower using the Long-staple cotton varieties, Table 1 (Textile Industries Holding Co.(2006) and Textile consolidation fund, 2006).

Table 1. Development of exported cotton yarn count-wise from 1994: 2006

The objective of this investigation was to study the quality characteristics of yarn spun from Egyptian cotton and its blends with Upland cottons to create an optimum quality yarns, and the usefulness of blending Egyptian/Upland cottons as a potential way of reducing the costs of popular fabrics.

Materials and Methods

The present study was carried out in Kom-Hamada, El Mahmoudia and Mit Ghamr spinning and weaving companies and Cotton Research Institute. Giza 85 Egyptian cotton variety (A) was chosen due to its color parameters and fiber length, and blended at different ten blend ratios for both Greek upland cotton (E) and Sudanese cotton (J). Cottons A, E and J were processed individually and carded at 3.54 g/m card sliver. Different Blend ratios were made at drawing frame with eight doubling to form six batches of second-drawing sliver of 3.20 g/m. The slivers of ten different blendes were supplied to the Schlafhorst Auotocoro 288 OE rotor spinning at rotor speed of 110,000 rpm for producing 25Ne and 35Ne and for producing 1.2 Ne roving for ring spinning at yarn size of 30 Ne and 40Ne. both OE and ring yarns were spun at constant twist multiplier 4.0.

Table 2. Processing outline

Cotton fiber and yarn properties were determined according to ASTM method by using HVI Spectrum and Micromat. Yarn strength expressed in terms of Lea Count Strength Product (LCSP) was measured by using the Good-Brand Lea Tester. Single yarn properties and yarn uniformity, imperfections and hairiness were measured on Textechno Statimat Me tensile tester and Uster Tester III, respectively. The results were compared with the Uster provisional 5%, 25% and 50% quality levels (Zellweger Uster, 2001). Fiber and yarn properties were determined at the Cotton Technology Research Laboratories, Cotton Research Institute, Giza, Egypt.

Results and Discussion

Fiber properties

Table 3 shows the quality properties of Egyptian cotton Giza 85, Upland Greek cotton and Acala Sudanese cottons. Naturally, the fiber quality of Egyptian cotton variety is higher than the two upland cotton varieties mainly, in fiber strength, fiber length, length uniformity, fiber fineness, fiber elongation and especially in short fiber index which reached in some samples of Greek and Acala cottons reached to 18.0 % accompanied by the lowest length uniformity, being 79%.

Table 3. Fiber quality properties of Giza 85, Greek and Acala cottons

Mechanical properties

The lea count strength product, single yarn strength and elongation of open-end and ring yarns spun from Giza 85 and its blends with Greek and Sudanese cottons are given in Tables 4, 5, 6 and 7. The results indicated statistical significant difference in lea count strength product and single yarn strength means of all blended open-end and ring yarns. Giza 85 cotton variety recorded the highest and superior quality of lea count strength product and single yarn strength (cN/Tex), while as, Greek and Sudanese cottons showed the lowest yarn quality. In both spinning systems and yarn counts, the addition of different ratio of Giza 85 cotton fiber improved the mechanical properties of the Greek and Sudanese cottons. The fact that long and strong fiber produced strong yarn held true for the two spinning systems used in this study.