Molecular reconstruction which translates the naturally round form of woollen fibres into a polygon is one of the treatments with which Japanese fabric producers are transforming the look and performance of 100 per cent wool and wool-rich fabrics for winter 2004/5.

Yarns which have received this treatment can be distinguished by their very un-wool-like pearly sheen and are now being offered to the trade under the brand name Optim.

Also making their debut in the global market, after first being previewed in this year's Japan Textile Contest, are what the Japanese are describing as Bio-tech wools. Having already been given an eco-friendly finishing treatment which makes them fully machine washable, the woollen fibres are then blended with a small quantity of linen to lend added textural interest.

Meanwhile, "patina" becomes the latest fabric finish in woollen fabric collections designed by Masukuri Mori. Ultra fine woollen fabrics are first dyed black and then impregnated with persimmon tannin, which produces a rusted look.

"Persimmon tannin is a substance traditional to Japanese textile manufacturing - we call it 'kaki-shibu'," says fellow Japanese designer Tokuji Naioh. His entry for the Japan Textile Contest centred around chenilles made from paper yarns.

By Sonia Roberts.