In the recent years, consumers have become increasingly aware of the need for sun protection, which is related to the incidence of sun induced skin damage and its relationship with increased exposures to UV light. UV radiation can lead to acute and chronic reactions and damage, such as acceleration of skin ageing and sunburn. Billions of people live on the earth and each has his or her own color of the skin. In human body the skin color depends on the quantities of melanin, carotene and oxygenated or reduced hemoglobin combined in the skin, as well as the thickness, water content etc. Among other factors, the quantity of melanin that is distributed in the skin determines its fairness or darkness and greatly influences the human complexion, at the same time melanin plays an important role in minimizing the damage that UV rays cause in the skin.

Protection of the skin against the action of solar radiation is a relatively new objective of textile finishing, since the textile does not always guarantee adequate protection. Specific protective functions of textiles against the most diverse influences are attracting more and more attention.
A notable objective of increasing interest in this area is the protection against UV radiation. The reason for this is the tendency for human to suffer increased harmful exposure to UV through natural radiation. The unfinished fabric has the limitation to guarantee adequate protection. Thus, a special additional sun protection finish is applied in the form of UV stabilizers. Electromagnetic radiations of wavelength between 150 and 400 nm are termed as Ultraviolet rays. Approximately 10% of sun’s energy is in the form of ultraviolet radiations. Atmosphere absorbs most of the noxious radiations emitted by the sun, only 5% of the harmful radiations reach to the surface of the earth.

All wave lengths of light including visible light affect fabrics to some extent. There are two critical elements for comprehensive protection and not just UV blocking property. UV absorbers such as Benzotriazole and phenyl benzotriazole, molecules are able to absorb the damaging UV rays of sunlight. UV absorbers convert UV energy in to harmless heat energy. This transformation is regenerative and can be repeated indefinitely. At the same time UV absorbers can cause discoloration, if used in higher concentrations. The construction of woven and knitted fabrics and the fiber types have a great influence on protection from ultraviolet transmittance. The ultraviolet protection factor (UPF) of textiles depends on their construction, the spaces between the yarns, their fiber types, the color, the textile impregnation, and the presence of optical brighteners and ultraviolet absorbers.

UPF also depends on the swelling capacity of the fibers. The UV blocking capacity of a fiber can be improved by incorporating TiO2 into its structure. Good skin protection, which is absolutely essential due to the accumulation of the radiation dose, is achieved by the textile itself with a sufficient weight of the fabric. In other case, e.g., light weight summer garments, a UV absorber can be applied either during fiber manufacture or in the final fabric finish which also offers the same degree of protection. Suitable organic or in organic products are also applied during this process. By using UV absorbers, exposure of the fabric to UV lights is reduced on the one hand as well as the intensity of the transmitted UV light on the other. To indicate the protection from UV radiation the term Sun Protection Factor {SPF} is widely used. SPF is a measure of how much a sun screen protects the skin protection products. SPF is a measure of how a sun screen protects the skin from burning and is measured by timing, as to, how long skin covered with sun screen .The term Ultra Violet Protection Factor { UPF } is widely used by the textile and clothing industry.

UPF is based on a vitro test method and it is a ranking of the sun protective abilities of textile. It is the ratio of an average effective ultraviolet radiation {UVR} irradiance calculated for unprotected skin to the average effective UVR irradiance calculated for skin protected by the test fabric. It is the quotient of the permitted radiation exposure relative to a minimum reddening of the skin in the protected area. The objective is to achieve factors between 30 and 50.