Construction of the Ch'ongsu Chemical Factory was completed in the early 1950s. In 1954, Dr. Lee Sŭng Ki directed the early stages of a pilot process to produce vinalon, a synthetic fabric, with a daily output of 20kg. However, in 1958, the Korean Workers Party adopted Cabinet Decision No. 122, "On Promoting Construction of a Vinalon and Vinyl Chloride Plant," and large-scale production of vinalon, approaching 20,000 tons annually, was established at the February 8th Vinalon Complex in Hamhŭng, South Hamgyŏng Province.

Sources:
[1] Various North Korean media reports in "DPRK's Ch'ongsu Chemical Factory, Suspect CW Site, Profiled," 22 November 2000, FBIS Document ID: KPP20001122000099;
[2] Osamu Eya, Kimu Jon Iru Daizukan (Tokyo: Shogakkan, 2000), pp. 64-65, in "Alleged Locations of DPRK Nuclear, Biological, Chemical Warfare Facilities Mapped," 6 June 2001, FBIS Document ID: KPP20010606000075;
[3] Inoue Tadao, Boei Gijutsu Janaru, December 1999, in "Ch'ongsu Chemical Factory Alleged CW Site," 11 January 2000, FBIS Document ID: FTS20000111000855;
[4] Yi Chae-sung, "Pukhan Kwahag'ŭi Isanggwa Hyŏnshil," Chapter Three in Pukhan'ŭl Umjiginŭn Technocrat (Seoul: Ilbit, August 1998), pp. 123-174, in "Chemical Engineering, Experts Described," 23 December 1999, FBIS Document ID: FTS19991223001168.