**3.4 Thickness and compression properties of woven fabrics**

Thickness and compressional properties of the fabric are very important characteristics in terms of fabric handle, especially for the fabrics used in garment manufacture. Fabric compressional characteristics depend on several factors like the compressional properties of the constituent warp and weft threads and the structure of the fabric (Mukhopadyhay et al., 2002).

The thickness of a fabric is one of its basic properties giving information on its warmth, heaviness or stiffness in use. In practice thickness measurements are rarely used as they are very sensitive to the pressure used in the measurement (Saville, 1999).

Fig. 5. The change in thickness with pressure (Saville, 1999)

Fabric thickness is generally evaluated by measuring the distance between two parallel plates separated by a fabric sample, with a known arbitrary pressure applied and maintained between the plates (Majumdar & Saha, 2008; as cited in BS Handbook, 1974).

Sensorial Comfort of Textile Materials 245

When a person runs their finger across the surface of a fabric, a complex multi-sensory, emotional and cognitive experience takes place. A memory is stirred, an emotion, feeling and association is evoked and a decision is made, an impression becomes embossed in the mind. Decisions and motivations are based on anticipated reality of preference, personality,

The subjective hand is the result of touch sensation and therefore is dependent on the mechanisms of human tactile sensations. The somatic senses are those nervous system mechanisms by which sensory information is collected from within body. The somatic

1. Mechanoreceptors – stimulated by mechanical displacement of various tissues at the

It is then clear that subjective hand sensing is the combination of various receptors responsible for feeling of texture, pressure, stretching, thermal feedback, dynamic deformation and vibration and from the sum of their complex responses humans can

In the subjective assessment process of textiles, fabric hand is understood as a result of psychological reaction through the sense of touch. There are variations in how individuals actually feel textiles because people do not have the same sensory perception of identical occurrences. Affecting aspects can be grouped in sociological factors and the physiological

The other main factors affecting the subjective handle evaluation can be defined as; the judges, the criteria of judgement, assessment conditions, assessment technique, the method of ranking and scaling the assessment, analysis of the results (Mahar et al., 1990; as cited in Brand, 1964; Bishop, 1996). Gender, age, education and cultural backgrounds are potential influencing factors. Female individuals in general respond more delicately and sensitively than male individuals and therefore have a finer assessment of a specific parameter

Since the services of expert judges are not widely available for research activities, generally students, laboratory assistants and other consumer groups work as panelists. Such panels should be capable of making consistent judgements of textile attributes and due to the high variability of these panelists compared to the expert judges, larger panel sizes should be

In order to ensure the reliability of subjective assessments, it is critical to choose the right expressions for the description of a fabric handle parameter (Mäkinen et al., 2005). There are different sensory attributes identified by numerous authors. These are grouped as given in Table 1 (Hu, 2008). The words "thickness," "thinness," "softness," "stiffness," "slippery," "roughness," "tightness," "fullness" and "pliable" are mostly used expressions to describe

Generally, in order to evaluate the handle of the fabric, fingers are slid on the surface of the fabric, compressed between the thumb and sign finger. The fingers containing more than

(Mäkinen et al., 2005; as cited in Kweon et al., 2004; as cited in Dillon et al., 2000).

preferred, at around 25-30 persons (Bishop, 1996).

the feel of a fabric (Sülar & Okur, 2007).

emotion and moods, for audience or non-audience participation (Moody et al., 2001).

senses are classified to the three groups:

2. Thermo receptors – stimulated by temperature changes 3. Nocio receptors – representing the human pain sense

perceive and discriminate between the textiles (Militky& Bajzík, 1997).

body

factors.

Figure 5 shows the change in thickness with pressure for a soft fabric together with the recovery in thickness as the pressure is removed. The steep initial slope of the curve makes it very difficult to measure thickness with any accuracy as a small change in pressure in this region causes a large change in measured thickness. Thickness at zero pressure always has to be obtained by extrapolation of the curve, as a positive pressure is needed to bring any measuring instrument into contact with the fabric surface (Saville, 1999).
