Fabric hand

Years of development have led to a standardized system for objective evaluation of fabric hand (129). This, the Kawabata evaluation system (KES), consists of four basic testing machines a tensile and shear tester, a bending tester, a compression tester, and a surface tester for measuring friction and surface roughness. To complete the evaluation, fabric weight and thickness are determined. The measurements result in 16 different hand parameters or characteristic values, which have been correlated to appraisals of fabric hand by panels of experts (121). Translation formulas have also been developed based on required levels of each hand property for specific end uses (129). The properties include stiffness, smoothness, and fullness levels as well as the total hand value. In more recent years, abundant research has been documented concerning hand assessment (130—133). 

Drape. Drape is closely related to fabric hand. Whereas hand is based on tactile criteria, drape refers more to a fabric s appearance by its tendency to fall into graceful, three-dimensional folds. Fabric drape depends to a laige degree on the same properties that influence hand, ie, flexural rigidity, thickness, and compressibility. Although stiffness is normally measured in a single direction, drape implies bending in all directions. 

Dimethyldichlorosilane. Because dimethyldichlorosilane has been polymerized to a silicone polymer on cotton fabrics to impart stain and water resistance and can be applied as a vapor, this agent was examined as a possible consolidant. This treatment also improves fabric hand, resistance to chemicals and weathering, resistance to abrasion (by reducing friction), and reduces the tensile strength loss when resin finishes are applied all factors that should make the material a desirable and effective consolidant. The reactions involved are as follows ... 

Fabric hand is defined as the estimated quality of a fabric, evaluated as reaction of the sense of touch, which is integrated in our brain to a total value. Important components of the sensory perception are the smoothness, compressibility and elasticity of the textile sample. As the hand of fabrics is primarily a subjective feeling - similar to the impression of colour - there have been many efforts to find methods for objective evaluation of the fabric hand. While instrumental colour measurement is very common in textile quality control, the automated measurement of fabric hand is still a topic of discussion and subjective manual hand evaluation is still the most important method. Simple methods to measure some aspects of fabric hand were described by Dawes and Owen. Many factors such as the colour of the textile, the hght and the surroundings, influence the manual evaluation of fabric hand. The American Association of Textile Chemists and Colorists has published guidelines for subjective hand evaluation. ... 

FAST (Fabric Assurance by Simple Testing) is another well known system. It was developed for quality assessment in the wool garment industry. FAST is less expensive and much quicker than the KES-F because it measures only some aspects of the fabric hand such as compression, bending, extension and dimensional stability at a few given points in a simplified form. The first three parameters correlate fairly well with the perceived softness but no quantitative hand values are calculated. For the evaluation of yam softness, there are several other devices in use, for example the p-Meter (Zweigle), a frictional balance (Reibwertwaage from Schlafhorst) and the F-meter. 

As can be seen, there are numerous instruments available to make objective, but incomplete, measurements of those physical properties that determine fabric hand. It is fair to say, however, that the best of these very expensive tools is, in general, not any better for making real time production decisions than an experienced finisher who knows what his or her customer expects. 

Kim C J and Vanghan E A, Physical properties associated with fabric hand , AATCC Book of Papers 1975 National Technical Conference, 1975, 78-95. 

In addition to the desired repellency effects, other undesirable fabric properties are often found with repellent finishes. These include problems with static electricity, poor soil removal in aqueous laundering, stiffer fabric hand, greying (soil redeposition) during aqueous laundering and increased flammability. Some fabric properties that are often improved by repellent finishes include better durable press properties, more rapid drying and ironing, and increased resistance to acids, bases and other chemicals. Table 6.1 shows typical textile applications for repellent fabrics and their requirements. 

Advantages of silicone water repellents include a high degree of water repel-lency at relatively low (0.5-1 % owf) on weight of fabric concentrations, very soft fabric hand, improved sewability and shape retention, and improved appearance and feel of pile fabrics. Some modified silicone repellents can be exhaust applied (to pressure-sensitive fabrics). 

Some potential difficulties with non-slip finishes include less flexibility and a harsher fabric hand (sometimes dry or fatty), dusting during cutting and sewing and delustering of fibres. 

Imparts weight to fabrics without effecting the fabric hand, durable press resin or dye shade... 

Fabric Properties after Treatment. Mens of the treatments altered fabric color, and only Ca(CXl)2 harshened the fabric hand, the samples exposed to nDrftoiine vapor were significantly weaker (87% of the (original strmgth) than fabric treated with water. 

Effect of mechanical and physical properties on fabric hand... 

Beheiy, H.M., 2005. Effect of Mechanical and Physical Properties on Fabric Hand, 1st edn. Wood-head Phibhshing Ltd, Cambridge, UK. 

Then, the rating values were correlated with statistical values, so-called fabric hands, (secondary performance) such as stiffness, fullness or flexibility of clothes. Finally, the values of fabric hands were compared with other empirical values, e.g., mechanical properties and surface characters of fibers (primary performance). He succeeded in obtaining excellent suits fabricated with polyester fibers, instead of wool fibers, by using the "Experimentel1e Aesthetic"- ike methods (but with more delicate processes). 

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