NotesCasein plastics are based on a protein found predominantly in milk, the word casein being derived from the Latin word 'caseus', which means cheese. Casein plastic was patented in Germany in 1899 . It was produced in rods, or sheets, made into knitting needles, pen barrels, or stamped out into buttons and buckles, then hardened in a mixture of formaldehyde. These products could be easily dyed into whatever colours were fashionable at the time.
Casein plastic was first introduced to the world under the product name 'Galalithe' at the Paris Universal Exhibition in 1900. In the following years the development process of casein plastics was undertaken by two companies; Vereinigten Gummivarenfabriken in Germany and Pellerin & Orosdi in France. These companies merged under the one name, International Galalithe Gesellschaft Hoff & Company, in 1904. The company developed a manufacturing process that used dried casein granules, which became the universal standard in processing casein, and remained virtually unchanged throughout its history. This type of plastic is rarely manufactured in the 21st century due to its labour intensive manufacturing process and the development of cheaper and more easily made products. Some also say that the popularisation of dairy products added to the demise of casein plastics.
The name 'Perspex' is a registered trade name for polymethyl methacrylate or PMMA. It is also known as Lucite in the USA, and Plexiglass in Germany. Perspex was trade marked in 1934 by Imperial Chemical Industries (ICI) in London. Perspex is a transparent acrylic that is hard and transparent. It was first developed as a safety glass and was manufactured into sheets and rods, which could then fabricated by machining, thermoforming, and engraving. The aircraft industry was the first major user of Perspex in the 1930s and it was widely used in military aircraft during World War II. Due to Perspex's excellent weathering resistance and light transparency, it was used in aircraft glazing, and as an alternative to glass in windshields and instrument panels. After the war, Perspex became easily accessible and was fashioned into all kinds of fancy dress goods, decorative objects, household goods, and found a particular application in the making of dentures.
Australia was the first to use Perspex in the manufacture of bathtubs in 1948. It was the first time Perspex had been used in such an application, initiated from the tremendous effort involved in moving heavy cast iron baths. The strong, durable, and easily coloured characteristics of the plastic, lent itself to being perfectly suited for the production of baths. This Australian innovation resulted in acrylic becoming the internationally preferred material for the production of baths by the 1990s. Perspex is still widely used as a safe alternative to glass in many industries such as medical technology, furniture, engineering, and the decorative arts.
John Morgan, From Milk to Manicure Sets the Casein Process, in the Journal of the Plastics Historical Society, No. 1, Winter, 1988, pg 13
M. Kaufman, The First Century of Plastics, The Plastics Institute, London, 1963. pg 55
Know Your Plastics, Plastics Industry Association Inc, Australia, 1980
Casein information sheet, Plastiquarian, available at: www.plastiquarian.com/casein2.htm, 2008.
John Acres, Seeing a Problem Through, Journal of the Plastics Historical Society, No 14, Winter, 1994/5, pg 4-5
A. R. Penfold, Modern Trends in the Manual Arts, lecture series, MAAS archive MRS 307-12/14:24