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, Ichiro Sakurada, and H. Kawakami.^[1] 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.^[2] Vinylon's widespread usage in North Korea is often pointed to as an example of the implementation of the Juche philosophy, and it is known as the Juche fiber.^[3]

PVF, in fiber form, is a useful thermoplastic resin on its own, most commonly used as electric wire insulation.^[4]

^ Patent no. 147,958, February 20, 1941, Ichiro Sakurada, Yi Sung-ki Lee. S. or Ri. Sung．Gi. and Hiroshi Kawakami, issued to Institute of Japan Chemical Fiber.^{[full citation needed]}
^ "Can North Korea sustain industrial growth?". The Korea Herald. 2010-08-18. Retrieved 2012-08-11.
^ Demick, Barbara (2009). Nothing to Envy: Ordinary Lives in North Korea. Spigel & Grau. p. 59. ISBN 978-0-385-52390-5.
^ "Plastics Technology". polymerdatabase.com.

[1] Patent no. 147,958, February 20, 1941, Ichiro Sakurada, Yi Sung-ki Lee. S. or Ri. Sung．Gi. and Hiroshi Kawakami, issued to Institute of Japan Chemical Fiber.^{[full citation needed]}

[2] "Can North Korea sustain industrial growth?". The Korea Herald. 2010-08-18. Retrieved 2012-08-11.

[Demick-3] Demick, Barbara (2009). Nothing to Envy: Ordinary Lives in North Korea. Spigel & Grau. p. 59. ISBN 978-0-385-52390-5.

[4] "Plastics Technology". polymerdatabase.com.

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