Oct. 16, 2009 — Darker colors in cotton fabric provide better protectionagainst the sun’s harmful ultraviolet rays than lighter tones, new researchindicates.
Scientists in Spain say people should “think blue or red” instead of yellowwhen choosing clothing, because the darker hues on cotton fabrics offer betterskin protection against the sun.
Their study is published in Industrial & Engineering ChemistryResearch.
Ascension Riva, PhD, of the Universidad Politecnica de Cataluna, andcolleagues used computer models to estimate levels of UV protection achievedwith three fabric dyes — red, blue, and yellow.
The researchers dyed cotton fabrics a range of red, blue and yellow shadesand measured the effectiveness of each dyed fabric to protect against UVlight.
Fabrics with darker or more intense colors had better UV protection, theresearchers say, and yellow shades offered the least.
The scientists say clothing manufacturers could use information from thestudy to design clothing that provides better protection against harmfulrays.
The researchers note that gaps exist in knowledge about exactly how colorinteracts with other factors to influence a fabric’s ability to block harmfulrays. They add that numerous studies have concluded that lighter-coloredsportswear worn in summer months does not provide enough protection.
The researchers write that “the color of cotton woven fabrics is a factorthat has a remarkable influence on their protection against ultravioletradiation” and that “the diffuse transmittance of ultraviolet radiation throughthe fabrics diminishes when any of the studied dyestuffs is applied.”