A dangerous photoresist (PR) liquid leaked at the SK Hynix Inc.\'s computer chip manufacturing plant in Cheongju, police and company sources said Thursday.The world\'s No. 2 memory chipmaker said the accident occurred in the so-called clean room belonging to the M11 production line at the plant located 137 kilometers southeast of Seoul. It said no one was hurt because everyone was wearing protective suits at the time. PR are not classified as harmful chemical agents under South Korean law, but are considered dangerous materials.