The reaction of
formaldehyde with urea, thiourea or melamine produces
thermosetting resins known collectively as aminoplastics.
(Resins formed from aniline with formaldehyde have been used for
specialised electrical insulation but were not generally
classified as aminoplastics.)
Resinous products prepared by heating urea with
excess formaldehyde were patented by John in 1918. Pollak and
Ripper in Austria developed clear liquid casting resins for the
production of 'organic glass' called Pollopas in the
early 1920s. Goldschmidt and Neuss in Germany and Ellis in USA
experimented with hot press moulding compositions based on urea
formaldehyde, but Rossiter of British
Cyanides Co. Ltd. developed the first commercial moulding powder
based n a mixture of urea and thiourea with formaldehyde in
1926. The possibility of a white or highly coloured
thermosetting material which could be moulded using techniques
developed for phenol formaldehyde (bakelite) was undoubtedly a
powerful incentive.
The use of urea formaldehyde resins for
impregnating cellulosic fibres to produce crease resistant
fabrics was developed by Tootal Broadhurst Lee Co. Ltd. in 1926.
In the early 1930s resinous solutions for
plywood adhesives were developed by I.G.Farben under the trade
name Kaurit and by de Bruyne
as Aerolite.
Resins derived from melamine and formaldehyde
were patented by Henkel in 1935 and these were found to possess
superior heat and moisture resistance, and thus found use for
plastics tableware.
Decorative laminated sheet was envisaged by
British Cyanides in 1924. Their use was pioneered by Formica in
USA using thiourea materials in 1931 and melamine in 1938.
Decorative laminates were used extensively on board the liner
Queen Mary in 1935.
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