Urea
formaldehyde
The first patent
on the condensation product of urea with
formaldehyde was by Hans John in about 1920 but
he used no catalyst. F Pollak and his co-workers
in Vienna used a variety of catalysts and took
out a number of patents between 1920 and 1924.
One of which was for a glassy transparent resin
which was given the name Pollopas. Their
efforts were directed towards the so-called 'organic
glasses' but this was not achieved until much
later by thermoplastics materials, especially
acrylics.
Goldschmidt and Neuss in
Germany also worked on urea formaldehyde but the
first commercially successful thermosetting
moulding material was produced by the British
Cyanides Co. - based on a mixture of thiourea and
urea formaldehyde in 1928.
I G Farben developed urea
formaldehyde especially as adhesives and stoving
lacquers with patents in 1925 and 1928. In 1933
the various firms making urea formaldehyde
materials agreed to exchange patent rights in
order to avoid possible disputes and rapid
development followed.
Thermosetting urea formaldehyde
moulding materials, unlike phenol formaldehyde,
was not limited in colour range and could be
produced in white and translucent shades, but
generally found similar applications. Being
somewhat more expensive than the phenolic
moulding compounds urea formaldehyde tended to be
used only where colour was important.
Initial uses were for electrical fittings,
telephone handsets, radio and other electrical
housings, cigarette boxes, lampshades, etc. and
tableware until replaced by melamine.
Urea formaldehyde impregnating resins are used in
decorative laminates.
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