Major British chemical corporation. It was founded in 1926 as Imperial Chemical Industries Ltd. to amalgamate four major British chemical companies. Between World Wars I and II, ICI was a major competitor of IG Farben. Today it produces industrial chemicals, paints, and explosives; its drug, pesticide, and specialty chemical concerns were split off into a new corporation, Zeneca Group PLC, in 1993. ICI's headquarters are in London