Charles Tennant was born in Ochiltree in Scotland in 1768. Educated at a local school he was apprenticed as a weaver. He studied bleaching and set up his own business in Paisley.
Charles Macintosh joined Tennant and in 1799 they took out a patent for the manufacture of a dry bleaching powder made from chlorine and slaked lime. The powder was in great demand in the textile industry and this enabled Tennant to build a new factory in Glasgow. At the time, it was the largest chemical works in the world. Charles Tennant died in 1838.