Japan's largest maker of synthetic fibres, Toray Industries Inc, on Tuesday posted a sharp rise in first quarter operating profit on the back of lower costs and higher sales and also raised its first half outlook.

The company said operating profit for the quarter to the end of June surged 123 per cent to 9.43 billion yen from 4.23 billion yen in the year-ago period as sales climbed six per cent to 251.7 billion yen from 236.7 billion yen last year.

Toray said it now sees a six month net profit of seven billion yen compared to its original forecast of two billion yen, with April to September operating profit seen at 21 billion yen on sales of 525 billion yen.