SK HOLDINGS CO., LTD.; PARK, Cheol-Hyoung; MIN, Hye-Kyung; LIM, Mi-Jung; LEE, Ji-Won; CHUNG, Jin-Yong; RYU, Choon-Ho; YOON, Yeo-Jin; JI, Mi-Kyung; PARK, Joo-Young Patent: WO2010/98600 A2, 2010 ; Location in patent: Paragraph 188-189 ;