**3. Fabric basic properties affecting sensorial comfort**

Fabric handle is related to the basic mechanical properties of fabrics, especially initial lowstress region of those properties (Mitsuo, 2006). Since the stresses involved in fabric handling are low compared with those applied in other types of textile performance testing (e.g. for ultimate tensile strength, tear strength, seam strength, etc), the methodology is sometimes referred to as measurement of "low-stress fabric mechanical and surface properties" (Bishop, 1996).

The stimulation of the feeling sensors greatly depend on the mechanical properties of the textile products, for instance a lower value of bending rigidity supports the positive impression of sensorial comfort (Ozcelik et al., 2005). The main mechanical and surface properties of fabrics that influence the sensorial properties of fabrics are tensile, bending, shearing and thickness (Figure 1).

Fig. 1. The types of fabric deformation (Hu, 2004)

#### **3.1 Tensile properties of woven fabrics**

Tensile properties are one of the most important properties governing the fabric performance during usage. Each pieces of fabric consist of large quantity of fibers and yarns, and hence any slight deformation of the fabric will lead to a chain of complex movements among these constituent fibers and yarns (Hu, 2004).

There are three stages for the extension mechanism. The first part is dominated by inter fiber friction that is the frictional resistance due to the yarn bending. Second part, a region of lower modulus, is the decrimping region resulting from the straightening of the yarn set in the direction of application of load, with the associated increase in crimp in the direction perpendicular to the yarn direction. This is commonly referred to as "crimp interchange".

Pigment printing is the most effective finishing process on the stiffness of the fabrics and mercerization before dyeing and printing results in improvements in various fabric properties; however cause negative effect in the fabric softness values (Özgüney et al., 2009). The effects of the stiffness and softening agents on the friction and stiffness properties of the fabrics are apparent. When compared to the untreated fabric, all the softening and stiffening treatments result in decrease in the both static and dynamic friction coefficient values. Especially for softeners, this decrease is obvious. Shirley stiffness values of the fabrics treated with stiffeners are quite higher compared to untreated one whereas all the fabrics treated with softeners have lower values. The most stiffening effect is obtained with starch

Fabric handle is related to the basic mechanical properties of fabrics, especially initial lowstress region of those properties (Mitsuo, 2006). Since the stresses involved in fabric handling are low compared with those applied in other types of textile performance testing (e.g. for ultimate tensile strength, tear strength, seam strength, etc), the methodology is sometimes referred to as measurement of "low-stress fabric mechanical and surface

The stimulation of the feeling sensors greatly depend on the mechanical properties of the textile products, for instance a lower value of bending rigidity supports the positive impression of sensorial comfort (Ozcelik et al., 2005). The main mechanical and surface properties of fabrics that influence the sensorial properties of fabrics are tensile, bending,

Tensile properties are one of the most important properties governing the fabric performance during usage. Each pieces of fabric consist of large quantity of fibers and yarns, and hence any slight deformation of the fabric will lead to a chain of complex movements

There are three stages for the extension mechanism. The first part is dominated by inter fiber friction that is the frictional resistance due to the yarn bending. Second part, a region of lower modulus, is the decrimping region resulting from the straightening of the yarn set in the direction of application of load, with the associated increase in crimp in the direction perpendicular to the yarn direction. This is commonly referred to as "crimp interchange".

**3. Fabric basic properties affecting sensorial comfort** 

(Namligöz et al, 2008).

properties" (Bishop, 1996).

shearing and thickness (Figure 1).

Fig. 1. The types of fabric deformation (Hu, 2004)

among these constituent fibers and yarns (Hu, 2004).

**3.1 Tensile properties of woven fabrics** 

The last part of the load extension curve, is due to the yarn extension. As the crimp is decreased, the magnitude of the loading force rises very steeply, and as a result, the fibers themselves begin to be extended. This is clearly a region of higher modulus (Figure 2a).

If the fabric undergoes in a cycling loading process, the fabric is first stretched from zero stress to a maximum and the stress is fully released, then an unloading process follows the loading process. As a result, a residual strain ε0 is observed, since textile materials are viscoelastic in nature. Due to the existence of residual strain, the recovery curve never return to the origin, as shown in Figure 2b. This is the hysteresis effect which denotes the energy lost during the loading and unloading cycle. Due to the existence of hysteresis, a deformed fabric cannot resume its original geometrical state (Hu, 2004; Schwartz, 2008).

Fig. 2. (a) Schematic of a typical load- extension curve for a woven fabric (Schwartz, 2008), (b) Loading and unloading cycle in the tensile stress-strain curve (Hu, 2004)
