Tokyo rubber futures extended losses on Thursday in the absence of fresh incentives.
The benchmark June 2004 rubber contract on the Tokyo Commodity Exchange (TOCOM) settled down 2.4 yen per kg at 139.7 yen.
Other months fell by 2.2 to 2.8 yen. "It's continuing to fall with nothing fresh to trade on," a Tokyo broker said.
The dollar was fetching 106.22/27 yen, against 106.18/20 yen at about the same time on Wednesday.
The benchmark contract's decline to below 140 yen may have accelerated moves to sell, resulting in a heavier volume, he said.
Turnover in TOCOM rubber was estimated at 13,584 lots, compared with 4,998 lots on Wednesday and 6,177 lots on Tuesday.
Open interest stood at 62,576 lots as of the end of Wednesday, versus 63,506 lots on Tuesday.