"The best performing fibres in the field of sun protection" is the way the Toray Textiles group assesses the latest generation of polyesters following recent independent tests carried out on samples from their range by the National Radiological Protection Board.

Toray, which claims to be the world's largest producer of polyester-based fabrics, recently submitted seven samples to the board to establish their CPP (Clothing Protection Factor). The samples were tested to British Standard 79l4:l998.2 and achieved the board's "very high" category rating, which requires that each fabric submitted must gain a greater than 30 CPF value.

In fact each of the Toray samples achieved a rating between l00 and 200 CPF, indicating mimimal ultra violet radiation penetration - somewhere between 0.005 and 0.01 per cent.

"Obviously there are other factors to be considered by cloth buyers seeking maximum sun protection fabrics - most notably the weight, colour, fibre type, thickness of the yarn and openness of the weave," Toray Textiles admits.

"However, the results of the recent tests are sufficiently conclusive to convince us that polyester provides the best sun protection currently available," says Toray's Jo Cooke, who now heads the recently formed outdoor clothing speciality division at Toray headquarters.

"Our own research has long since led us to similar conclusions," says Jo. "Now that our assessments have been individually substantiated we can start seriously exploiting the potential of these high performance polyesters as the most functional fabric choices for garment manufacturers in the activewear field."

Initially Jo sees the strongest take-up coming from manufacturers serving the trek, safari, mountain and exploration wear markets, but adds that in a world where the general public is becoming increasingly aware of the dangers of over exposure to the harmful effects of the sun the long term future of sun protective polyester fabrics will lie with much wider applications.

"We see golfers, cyclists, ramblers and summer team sports participants such as cricketers as future customers," says Jo, adding that when moving into a more mainstream market the versatility of polyester in terms of dye and speciality finish acceptance will be very much to the fibre's advantage.

By Sonia Roberts