The first semi-synthetic material was ebonite. In the early 1840s, Charles Goodyear manufactured a very hard, black rubber compound, also containing sulfur and linseed oil, called “ebonite”. (The material was once also called “vulcanite” but that name is now reserved for the mineral vulcanite.)
Some uses of the material included fountain pen bodies, combs, the mouthpieces of pipes and musical instruments, bowling balls and car battery cases.
The material is brittle. Under the influence of daylight, sulfuric acid is produced at the surface which gradually discolors the surface from gray green to white.
The first true thermoplastic was celluloid, invented in 1856. It is a compound of nitrocellulose and camphor, with added dyes and other agents.
Celluloid was used for as a cheap alternative to ivory, horn or tortoise shell in items such as jewellery, jewellery boxes and hair accessories. It was also used for dolls, buttons, buckles, musical instrument parts, fountain pens and cutlery handles. It was often referred to as “Ivorine”.
Clocks and other furniture was sometimes covered with celluloid which was painted to look like expensive wood, marble or granite. This was sometimes called “adamantine”.
Celluloid is highly flammable and difficult and expensive to produce. Its main remaining use is for table tennis balls.
In 1907, Leo Baekeland, patented the first totally synthetic resin, phenol formaldehyde, or “Bakelite”.
Bakelite was particularly useful in the emerging electrical and automobile industries because of its extraordinarily high resistance to electricity, heat and chemical action. A myriad of other applications were found, including telephone housings and handsets, musical instrument mouthpieces, cameras bodies, pipe stems, buttons and appliance casings.
In 1939, Leo Baekeland companies were acquired by Union Carbide. In addition to the original Bakelite material, Union Carbide eventually made a wide range of other products, many of which were marketed under the brand name “Bakelite plastics”.
After the Second World War, Bakelite was produced using a more efficient extrusion process, which increased production and its range of uses including for jewelry boxes, desk sets, clocks, radios, game pieces like chessmen, billiard balls, canisters and tableware.
It is still used for inexpensive game pieces, such as dominoes and draughts pieces.
Bakelite is made from phenolic resin and wood flour. Phenolic resin can be cast in lead moulds, rather than extruded like bakelite. Bakelite usually has a dark mottled appearance due to the presence of “fillers”. These were needed to strengthen the material for the extrusion process. Casting phenolic resin avoids the need for fillers. The result is a far wider range of strong bright colours than is possible with true Bakelite.
Cast phenolic resin was used to make art deco style jewellery and radio cases.
In 1919, Hanns John in Czechoslovakia patented urea-formaldehyde resin.
This soon became popular, particularly for tableware, as “Beetleware” and “Bandalasta”.
Urea-formaldehyde began to be replaced in molded articles in the 1950s by melamine-formaldehyde resin (“melamine”) and by new thermoplastic resins such as polystyrene.
Urea-formaldehyde is still used in many manufacturing processes. Its chief use today is in bonding particleboard.