Process of viscose
Viscose is a
viscous organic liquid
used to make rayon
and
cellophane.
Cellulose
from wood or
cotton fibres
is treated with
sodium hydroxide, then mixed with
carbon disulfide to form cellulose
xanthate,
which is dissolved in more sodium hydroxide. The resulting viscose is extruded
into an acid bath either through a slit to make
cellophane,
or through a
spinneret to make
rayon. The acid converts the viscose back into cellulose.
Cellulose is treated with alkali and carbon disulfide to yield
viscose.
Viscose was created by French scientist and industrialist
Hilaire de Chardonnet (1838-1924), inventor of the first artificial textile
fiber, artificial silk) in
�chirolles
in 1884, then the
process for manufacturing viscose was patented by three British scientists,
Charles Frederick Cross,
Edward John Bevan and
Clayton Beadle, in
1891.
Industrial applications
Viscose was first used for coating fabrics, a purpose for which it is quite
suitable. However, when
Cross and his partners tried to make solid objects like umbrella handles
they were found to be much too brittle.
Further development led to viscose being spun into thread for embroidery and
trimmings. Eventually, after
Samuel Courtauld & Co. had taken over in
1904, Viscose
manufacture became big business. By the twenties and thirties it had almost
completely replaced the traditional cotton and wool for women�s stockings and
underwear. Similar changes occurred in the US and in Europe, too. Viscose was
also being used for linings and furnishing fabrics; providing the staple for
towels and table-cloths and was being made into high tenacity yarn for tires.
Yet other uses included the manufacture of sponges and absorbent cloths.
Making viscose film had been tried by Cross in the 1890s but it was in
Switzerland and France that major successes were achieved. By 1913 C.T.A.
established La Cellophane SA. Ten years later
DuPont Cellophane
Co. was set up in the USA and in 1935
British Cellophane Ltd was established in
Bridgwater,
Somerset.
Viscose is a soft material, used in mostly tops, coats and jackets.
Viscose is currently becoming less common because of the polluting effects of
carbon disulfide and other by-products of the process, forcing the Bridgwater
factory to close in
2005.
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