US fibre giant DuPont Textiles & Interiors (DTI) has revealed modest second quarter sales growth but said they were offset by lower selling prices. The company, which comprises DuPont's nylon fibres, polyester fibres, Lycra brand fibre and spandex businesses, plus their intermediates and joint ventures, said it operating profit after tax soared to $91 million from $7m in the year-ago period.