[TOKYO] The Bank of Japan's unprecedented stimulus has helped Mitsui OSK Lines overcome a junk rating threat as bond investors held onto the notes of the world's largest merchant shipping line.

The extra yield over government debt that investors demand to own the company's 0.461 per cent bonds due 2017 fell two basis points to a record 22 basis points on Aug 5, the day after Moody's Investors Service placed Mitsui OSK's Baa3 rating on review for downgrade. That's one basis point above the average spread for Japanese companies, while corporates worldwide pay 112, according to Bank of America Merrill Lynch data.

Moody's cited increased leverage as Mitsui takes on more debt to finance expansion of its liquefied natural gas business while global demand for containership and dry bulk transport remained weak.