Vinylon, also known as Vinalon (more common in Korean sources), is a
synthetic fiber
Synthetic fibers or synthetic fibres (in British English; see spelling differences) are fibers made by humans through chemical synthesis, as opposed to natural fibers that are directly derived from living organisms, such as plants like cott ...
produced from reaction between
polyvinyl alcohol
Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water- soluble synthetic polymer. It has the idealized formula H2CH(OH)sub>''n''. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) a ...
(PVA) fiber and
formaldehyde
Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...
. Chemically it is polyvinyl formal (PVF). Vinylon was first developed in
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
in 1939 by ,
Ri Sung-gi, and H. Kawakami. In
North Korea
North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korea, Korean Peninsula and borders China and Russia to the north at the Yalu River, Yalu (Amnok) an ...
,
Ri Sung-gi found a route to produce PVA from domestic
anthracite
Anthracite, also known as hard coal and black coal, is a hard, compact variety of coal that has a lustre (mineralogy)#Submetallic lustre, submetallic lustre. It has the highest carbon content, the fewest impurities, and the highest energy densit ...
(black coal) and
limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...
as raw materials. Trial production began in 1954 and in 1961 the massive "Vinylon City" was built in
Hamhung
Hamhŭng (''Hamhŭng-si''; ) is North Korea's List of cities in North Korea, second-most populous city, the capital of South Hamgyong, South Hamgyŏng Province and the 16th largest city in the Korea, Korean Peninsula. Located in the southern part ...
,
North Korea
North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korea, Korean Peninsula and borders China and Russia to the north at the Yalu River, Yalu (Amnok) an ...
. Vinylon's widespread usage in North Korea is often pointed to as an example of the implementation of the ''
Juche
''Juche'', officially the ''Juche'' idea, is a component of Ideology of the Workers' Party of Korea#Kimilsungism–Kimjongilism, Kimilsungism–Kimjongilism, the state ideology of North Korea and the official ideology of the Workers' Party o ...
'' philosophy, and it is known as the ''Juche'' fiber.
PVF, in fiber form, is a useful
thermoplastic
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.
Most thermoplastics have a high molecular weight. The polymer chains as ...
resin on its own, most commonly used as electric wire insulation.
Applications
Vinylon is the national fiber of North Korea and is used for the majority of textiles, outstripping fiber such as
cotton
Cotton (), first recorded in ancient India, is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure ...
or
nylon
Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups.
Nylons are generally brownish in color and can possess a soft texture, with some varieti ...
, which is produced only in small amounts in North Korea. Other than clothing, vinylon is also used for shoes, ropes, and quilt wadding.
Japanese-Canadian textile artist
Toshiko MacAdam used vinylon in her early works, as it was more economical than
nylon
Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups.
Nylons are generally brownish in color and can possess a soft texture, with some varieti ...
.
Swedish outdoor brand
Fjällräven makes their popular Kånken backpack line out of a version of vinylon, branded Vinylon F.
Properties
Vinylon is resistant to heat and chemicals but has several disadvantages: being stiff, having a relatively high manufacturing cost, and being difficult to dye.
Production

The production process by Ri is as follows:
* Limestone and coal are mixed to produce
calcium carbide
Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of . Its main use industrially is in the production of acetylene and calcium cyanamide.
The pure material is colorless, while pieces of technica ...
.
* The carbide is used to produce
acetylene
Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is u ...
gas.
* Reaction with
acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
produces
vinyl acetate
Vinyl acetate is an organic compound with the Chemical formula, formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate, ethylene-vinyl acetate copolymers, polyvinyl alcohol, and other important industrial polymers.
Prod ...
.
*
Polymerization
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...
produces
polyvinyl acetate (PVAc).
* Hydrolysis of PVAc produces
polyvinyl alcohol
Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water- soluble synthetic polymer. It has the idealized formula H2CH(OH)sub>''n''. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) a ...
(PVOH).
* PVOH is stretched into a fiber and spun.
* The PVOH yarn is finally reacted with
formaldehyde
Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...
to make vinylon, a chain of
acetal
In organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments n ...
s and
hemiacetal
In organic chemistry, a hemiacetal is a functional group the general formula , where is a hydrogen atom or an organic substituent. They generally result from the nucleophilic Addition reaction, addition of an Alcohol (chemistry), alcohol (a compo ...
s.
Other locations may use alternative feedstocks to synthesize PVOH.
History
1939: colonial introduction
Between the years 1910 to 1945, Korea was ruled as a
Japanese colony. This fact forced the integration of Korea into the Japanese empire's economic and political spheres. Thus, after the
Second Sino-Japanese War
The Second Sino-Japanese War was fought between the Republic of China (1912–1949), Republic of China and the Empire of Japan between 1937 and 1945, following a period of war localized to Manchuria that started in 1931. It is considered part ...
began in 1937, Korea was integrated into the Japanese war effort. It was amid Japan's efforts towards creating a more scientific and technologically advanced country for the war when a team of researchers worked to fabricate Vinylon.
The first successful creation of Vinylon was in 1939, by a
Kyoto University
, or , is a National university, national research university in Kyoto, Japan. Founded in 1897, it is one of the former Imperial Universities and the second oldest university in Japan.
The university has ten undergraduate faculties, eighteen gra ...
research team in Japan,
[Lee, Hy-Sang. North Korea : a Strange Socialist Fortress. Westport, Conn., Praeger, 2001.] using petroleum as the feedstock.
However, Vinylon was later brought to North Korea by Ri Sung-gi, one of the researchers of the Kyoto University team, amid North Korean campaign aimed at the recruitment of scientists and engineers from
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia. It constitutes the southern half of the Korea, Korean Peninsula and borders North Korea along the Korean Demilitarized Zone, with the Yellow Sea to the west and t ...
in the period following Korea's liberation from Japan in 1945. He was working as a professor at
Seoul National University
Seoul National University (SNU; ) is a public university, public research university in Seoul, South Korea. It is one of the SKY (universities), SKY universities and a part of the Flagship Korean National Universities.
The university's main c ...
at the time.
During the
Korean War
The Korean War (25 June 1950 – 27 July 1953) was an armed conflict on the Korean Peninsula fought between North Korea (Democratic People's Republic of Korea; DPRK) and South Korea (Republic of Korea; ROK) and their allies. North Korea was s ...
, when
Seoul
Seoul, officially Seoul Special Metropolitan City, is the capital city, capital and largest city of South Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's List of cities b ...
was occupied by the
Korean People's Army
The Korean People's Army (KPA; ) encompasses the combined military forces of North Korea and the armed wing of the Workers' Party of Korea (WPK). The KPA consists of five branches: the Korean People's Army Ground Force, Ground Force, the Ko ...
, Ri was offered a research position in North Korea.
Ri Sung-gi accepted and defected to the North.
He found a way to produce Vinylon from coal.
1961: Vinylon City, Hungnam
After the
liberation of Korea
Liberation or liberate may refer to:
Film and television
* ''Liberation'' (film series), a 1970–1971 series about the Great Patriotic War
* "Liberation" (''The Flash''), a TV episode
* "Liberation" (''K-9''), an episode
Gaming
* '' Liberati ...
in 1945, North Korea was under
Soviet
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
occupation and thus provided with aid by the Soviets as a means to stabilize the country. Beginning at the end of the Korean War in 1953, the Soviet Union,
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
, and other
communist countries
A communist state, also known as a Marxist–Leninist state, is a one-party state in which the totality of the power belongs to a party adhering to some form of Marxism–Leninism, a branch of the communist ideology. Marxism–Leninism was ...
began actively providing foreign aid to North Korea.
[Kim, Jiyoung. “The Politics of Foreign Aid in North Korea.” The Korean Journal of International Studies , vol. 12, no. 2, Dec. 2014, pp. 425–450.] Therefore, the North Korean economy heavily depended on aid from other socialist countries.
However, in the 1960s, the aid from the Soviet Union decreased. North Korea was no longer receiving aid in the form of grants, but loans.
Hence, the North Korean leadership decided to accelerate efforts towards developing a self-sufficient economy. This resulted in the full mobilization of domestic resources.
Beginning in 1961, North Korea launched its
First Seven-Year Economic Development Plan, which focused on technological innovations, cultural revolution, improvement of living standards, modernization of the economy, and the facilitation of trade and international economic cooperation.
As a result, the North Korean government decided to develop the vinylon industry and build the February 8 Vinylon Complex, nicknamed Vinylon City.

In the early stages of North Korea's history, the government under
Kim Il Sung
Kim Il Sung (born Kim Song Ju; 15 April 1912 – 8 July 1994) was a North Korean politician and the founder of North Korea, which he led as its first Supreme Leader (North Korean title), supreme leader from North Korea#Founding, its establishm ...
and the official "''
Juche
''Juche'', officially the ''Juche'' idea, is a component of Ideology of the Workers' Party of Korea#Kimilsungism–Kimjongilism, Kimilsungism–Kimjongilism, the state ideology of North Korea and the official ideology of the Workers' Party o ...
''" (self-reliance) ideology promoted the idea that the only way to reach the goal of economic independence was through heavy machine industry. The manufacturing of vinylon was therefore taken as a step towards developing North Korea as a modern industrial state. With such an appeal to nationalism, the North Korean government mobilized its citizens for constructing and supporting a new vinylon factory, called Vinylon City.
In 1961, Vinylon City, the factory compound for producing vinylon, was built in the northeastern industrial city of
Hungnam
Hŭngnam () is a district of Hamhung, the second largest city in North Korea. It is a port city on the eastern coast on the Sea of Japan. It is only from the slightly inland city of Hamhung. In 2005 it became a ward of Hamhung.
History
The por ...
. The construction of the factory took fourteen months, which was quite fast considering that fifty buildings made up Vinylon City. Vinylon City had a total floor space of , 15,000 production machines, 1,700 container tanks, and of piping.
The tallest building in Vinylon City, measuring in height with a smokestack, was the
acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
shop.
The spinning shop, which was responsible of creating the vinylon fiber and shipping, was the largest building— long and wide, with floor space.
Vinylon City became the pride of North Korea, being touted as having been built without foreign assistance. The success of Vinylon City demonstrated independence from the Soviet Union and China and appeared to reflect the ''Juche'' ideology. Even though workers had to complete dangerous tasks and some ultimately lost their lives for the sake of demonstrating the country's capabilities,
vinylon thus served as a reinforcement of the party's ideological command and the
Kim family's rule.
The city began with a goal of producing enough fiber to supply the entire country with clothing, shoes, and other necessities, a goal that appears to have been met for several decades. The fiber produced from Vinylon City was considered so important that during the annual commemoration of
Kim Il-sung's birthday
The Day of the Sun () is an annual Public holidays in North Korea, public holiday in North Korea on 15 April, the birth anniversary of Kim Il Sung, founder and Eternal President of North Korea. It is the most important national holiday in the ...
, the people were given gifts of vinylon clothing. The factory is said to have hit a production ceiling in 1973. A second complex was planned in 1983 but never built.
1990s–2000s
The North Korean economy suffered enormously after the
collapse of the Soviet Union
The Soviet Union was formally dissolved as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. Declaration No. 142-Н of ...
, culminating in the
North Korean famine
The North Korean famine (), dubbed by the government as the Arduous March (), was a period of mass starvation together with a general economic crisis from 1995 to 2000 in North Korea. During this time there was an increase in defection from N ...
of 1994-1998. In 1994, the complex was forced to close due to coal shortages.
[“Kim Jong-Il attends factory reopening ceremony.” The hankyoreh, The Hankyoreh Media Company, Mar. 2010.]
After the North Korean economy recovered, the complex remained closed until 2010. During this time, the vinalon market was replaced by other fabrics, some made domestically, others imported from China. One defector said that only the army continued to purchase this material.
2010 reopening
On February 8, 2010,
Kim Jong Il
Kim Jong Il (born Yuri Kim; 16 February 1941 or 1942 – 17 December 2011) was a North Korean politician who was the second Supreme Leader (North Korean title), supreme leader of North Korea from Death and state funeral of Kim Il Sung, the de ...
visited the former Vinylon City complex in Hamhung to celebrate its reopening.
Kim was accompanied by high-ranking officers of the party, such as the Chairman of the Presidium of the Supreme People's Assembly
Kim Yong-nam, Defense Minister
Kim Yong-chun and Korean Workers’ Party secretaries
Kim Ki-nam and
Choi Tae-bok.
This was the first documented time he ever attended an industrial mass rally. While his attendance, and that of the most important party members, could signify the importance of the vinylon complex and its role in advancing the economic policies of Kim Jong Il, there is evidence that the facility could play a role in the North Korean nuclear weapons program. Based on an analysis of satellite imagery, information from
Ko Chong-song (a North Korean official who had defected), and a number of North Korean technical documents, there is speculation that the Hamhung plant is manufacturing
unsymmetrical dimethylhydrazine
Unsymmetrical dimethylhydrazine (abbreviated as UDMH; also known as 1,1-dimethylhydrazine, heptyl or Geptil) is a chemical compound with the formula H2NN(CH3)2 that is primarily used as a rocket propellant. At room temperature, UDMH is a colorle ...
, a rocket fuel that is used in North Korean long-range missiles.
In his new-year speech for 2017, Kim Jong Un expressed plans to revamp the Vinylon City.
Historical significance
Although vinylon was initially used to help develop the North Korean economy as a home-grown product, it also became intertwined with nationalism. As a result, vinylon became a firm part of the North Korean national identity.
References
Further reading
*
External links
NKChosun.comFibers-Poly-Vinyl-Alcohol
{{Authority control
Korean clothing
Science and technology in North Korea
Synthetic fibers
Korean inventions
Japanese inventions