Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 148,137 pages of information and 233,680 images on early companies, their products and the people who designed and built them.
of Lightpull Mills, Stroud, Gloucs. London Office at Regent Street, W1. Birmingham Office at Coleshill Street. (1922)
Ditto all addresses. Telephone: Stroud 810 (5 lines). Cables: "Erinoid, Stroud". (1947)
1909 Casein plastics, derived from milk, were developed by Erinoid.
1914 Erinoid Ltd of Rodborough, was established at Lightpill Mill, near Stroud. The firm manufactured plastic using casein, a substance derived from milk by a patented dry process.
The factory quickly became the main source of casein plastic in the UK, producing at least 5 tons a week at the start of the First World War.
1922 British Industries Fair Advert (double page) for Erinoid - The New British Insulating Material. A Non-Inflammable Substitute for: Celluloid; Bone; Amber; Ebonite; Horn; Coral; Fibre; Ivory; Jet; Vulcanite; Tortoiseshell; Turquoise. Ideal for Turning and admirably suitable for: Electrical Fittings and Accessories; Buttons, Beads, Combs and Hair Ornaments; Cigarette Holders; Knife Handles; Pencils and Penholders; Hat Pins; Umbrella and Stick Handles; Organ Stops; Piano Keys, etc. (Stand No. K.51) 
The business continued to expand rapidly, and employed over 500 people by 1933.
1947 British Industries Fair Advert as Manufacturers of Modern Plastics Materials: Casein; Cellulose Acetate; Vinyl Plastics; Polystyrene; Oil Soluble Synthetic Resins. (Plastics Section - Earls Court, 1st Floor, Stand No. 808) 
In 1973, when 700 people were employed, the factory also made polystyrene and articles in thermo-plastic materials for use in the electrical and building industries.
The Stroud-based factory remained the major producer of casein plastic right up to the 1980s, when it ceased manufacture faced with a dwindling market.
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