This follows an earlier order for four identical car carriers to be built by Shin Kurushima Dockyard Co. Ltd and Japan Marine United Corporation.
Each company will build four car carriers for the shipping line, with delivery starting in 2015 and continuing through the first quarter of 2017.
"By adding this series of eight new ships with better stability of the vessel and better fuel efficiency, we continue to deliver value added efficiency and capability of handling an even wider variety of cargo mix to assure our services successfully meet the needs of our valued customers in order to be best suited for not only passenger cars but also other ro-ro cargo," a company statement said.