Japanese financial services provider Orix Corp (8591.T) said it would buy accounting software maker Yayoi Co from private equity firm MBK Partners for more than 80 billion yen ($691 million), as it tries to expand its customer base into smaller companies.

Orix will take a 99.9 percent stake in Yayoi from MBK, it said in a statement. Yayoi makes software for calculating salaries, making price estimations and filing taxes.

Orix will tap demand from small companies which want to boost efficiencies in these operations, it said.

MBK Partners bought Yayoi for 71 billion yen in 2007 at the height of the leveraged buyout boom.

Orix will borrow over 30 billion yen for the acquisition, a company spokesman said.