In this paper, full and hollow fibers having round and trilobal cross-sectional shapes were produced in equal manufacturing conditions and bending, drapability and crease recovery behaviors of the woven fabrics produced from these fibers were investigated. The bending rigidities of the fabrics produced from hollow fibers were higher than the bending rigidities of the fabrics produced from full fibers. The highest bending rigidities were obtained in fabrics produced from hollow round fibers. The bending rigidities and drapabilities of the fabrics produced from fibers of similar cross-sectional shapes were in close relation with each other. The fabrics produced from full fibers had higher drapabilities than those produced from hollow fibers. The fabrics produced from full fibers had higher crease recovery angles than those produced from hollow fibers. Considering that the construction properties of the fabrics were kept constant, it could be concluded that the differences among the properties of the fabrics which were produced from full and hollow fibers (for both round and trilobal cross-sectional shapes) basically emerged from the very high differences between moments of inertia of full and hollow cross sections. It was also considered that another factor which caused differences between the fabric properties was the different bulkiness of the fibers and also the different bulkiness of the yarns with the same counts. The best results could be obtained with round and trilobal full fibers at fabrics in which drapability and crease recovery are desired.

This paper assesses color differences and percent reflectance changes occurring in nine dyed cotton fabrics after different cycles of abrasion for different fabric construction parameters. The fabrics differ from each other in their weft yarn types and counts, weft densities, and weft yarn twists. Warp yarn type and count, warp density, warp yarn twist, and fabric weave are the same for all fabrics. Fabric samples are dyed in a commercial red direct dye (CI Direct Red 89) and four different abrasion cycles (2500, 5000, 7500, 10000) are used. The percent reflectance of the abraded fabrics is measured, and color differences between the original (control fabric, dyed but not abraded) and abraded fabrics are calculated. The main differences in percent reflectance and color difference values are observed between 0 and 2500 cycles of abrasion. Increasing abrasion cycles after 5000 do not change the reflectance and color difference values of the fabrics significantly. The rubbing motion of the Martindale instrument apparently creates a combing effect on the fibers of the fabric surface at higher abrasion cycles, which makes the surfaces look more regular and avoids greater color differences. The main effect of abrasion on percent reflectance and color differences occurs up to 5000 cycles. Photographs of the control and fabrics abraided 10,000 times are presented to show changes in the alignment of fibers after abrasion.

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Carrier dyeing is a method of dyeing polyester materials that is used when necessary. Although usage of carriers in dyeing enables the dyeing of polyester materials at atmospheric pressure, the undesirable properties of the carriers are drawbacks. Disperse dyes are classified under different energy levels and the dyeing methods and color and fastness properties of dyed materials are associated with this classification. Carriers can be used when dyeing at higher temperatures than 100°C to promote the leveling of the more difficult disperse dyes. In the presence of a carrier substance in the dye bath, the dyeing behavior of the disperse dyes may become sensitive to dyeing temperature and dye bath concentration changes. Disperse dyes may show distinct dyeing properties in combination dyeing in carrier dyeing although they belong to the same energy level. Color-matching operations made by using a color-matching software must take the sensitivity of both dye bath concentration and dyeing temperature of the disperse dyes into account in the carrier dyeing of polyester fibers. According to the experimental results obtained on individual disperse dyes in the present study, problems may arise in carrier dyeing of polyester fibers with disperse dyes in combination dyeing because of the different dyeing temperature and dye bath concentration sensitivity of dyes that have the same energy level. Combination dyeing must not be performed close to dyeing temperatures of 100°C when dyeing in the presence of a carrier.

The relationship between surface roughness, fabric balance and percentage reflectance of various types of fabrics based on polyester yarn has been investigated. The warp yarn type and count, warp density and warp yarn twist were kept constant while the effect of variation in weft density, weft yarn filament number, fiber fineness and weave pattern were studied. Measurements were conducted on pre-treated undyed fabric samples and the results assessed in relation to their constructional properties. A change in weave pattern from plain to satin increased the percentage reflectance and surface roughness, but decreased the fabric balance. An increase in weft density similarly increased the percentage reflectance and fabric balance, but decreased surface roughness. The relationship of percentage reflectance to surface roughness and fabric balance implied that light reflectance from the fabric surface was dependent on weave pattern, on weft density and on fiber fineness. The long yarn floats present in satin fabric structures increased light reflectance from the fabric surface, but increased the fabric surface roughness and decreased the fabric balance due to the looser fabric structure.

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