For
comfort of human body, the temperature of textile materials for clothing must
be near 98.6oF. Our clothing should be capable of adjustment to changes
in climate, as light as possible in weight, permeable to air and to water
vapour, but capable of repelling liquid water when necessary.
Textile
fibres do not possess great insulating powers, and that the thermal insulation
value of textile fibre is largely due the air entrapped within the mass.
Importance of the entrapped air is not only responsible for warmth of the
material, but also the layer of air between the fabric and the skin. It may be
slated broadly that the greater the area of contact between the fabric and the
skin, the ‘cooler’ the fabric; similarly, the less the area of contact, the
‘warmer’ the fabric. For instance, Linen- cool feeling for smoothness and
maximum contact with skin; Wool- highly crimped fibre whose yarn construction
comprises a random arrangement, the composition of these two factors producing
minimum contact with skin and resulting in the sensation of warmth.
