Oct. 15 (HealthDay News) -- Deep blue and red cotton fabrics are better than yellow at protecting skin against damaging ultraviolet (UV) radiation from the sun, according to Spanish scientists.

The researchers said their findings could lead to clothing fabrics that offer improved sun protection.

The color of fabric is one of the most critical factors in determining how well clothing protects people against UV radiation. But there are gaps in knowledge about exactly how color interacts with other factors to influence the degree of UV protection offered by a fabric, explained Ascension Riva of the Universidad Politecnica de Cataluna in Terrassa, Spain, in a news release from the American Chemical Society.

The researchers dyed cotton fabrics in a wide range of red, blue and yellow shades and measured the ability of each to absorb UV light. Deep blue shades had the highest UV absorption, while yellow shades had the least, they found.

The results, scheduled to be published in the Nov. 4 issue of the journal Industrial & Engineering Chemistry Research, could be used by clothing makers to design more effective anti-sun clothing, Riva and colleagues suggested.

SOURCE: American Chemical Society, news release, Oct. 15, 2009