The Bank of Japan's tankan corporate sentiment survey, due Wednesday, is expected to show a slight deterioration but largely shrug off the negative impact of the Middle East conflict, according to economists polled by data provider Quick. The diffusion index measuring sentiment among large manufacturers is expected at plus 16 in the June survey, compared with plus 17 in March. "While business sentiment among material sectors is believed to have deteriorated due to surging resource prices and supply shortages driven by the situation in Iran, sentiment among processing sectors likely improved on the back of robust semiconductor-related demand," says Mizuho Securities economist Ryosuke Katagi. (megumi.fujikawa@wsj.com)