وینایلون

Also known as vinalon, polyvinyl formal, Juche fiber, PVF

thumb|North Korean men wearing uniforms made from vinylon Vinylon, also known as Vinalon (more common in Korean sources), is a synthetic fiber produced from reaction between polyvinyl alcohol (PVA) fiber and formaldehyde. Chemically it is polyvinyl formal (PVF). Vinylon was first developed in Japan in 1939 by , Ri Sung-gi, and H. Kawakami. In North Korea, Ri Sung-gi found a route to produce PVA from domestic anthracite (black coal) and limestone as raw materials. Trial production began in 1954 and in 1961 the massive "Vinylon City" was built in Hamhung, North Korea. Vinylon's widespread usage