Robert Stanley Mitchell (1877-1930) was born at Derby, the son of Robert Thomas Mitchell, a printer compositor, and his wife, Katharine née Ackerman.  In 1903, Robert married Grace Elshaw.  In the Census (1911), Robert and Grace lived at Hillsborough, when his occupation was ‘foreman, engineer’ at a cutlery works.  In about 1914, he began to manufacture safety razors at Unity Works, Langsett Road, Walkley.  The firm became a private limited company in 1927, with £5,000 capital, and with Robert S. Mitchell and his wife as directors.  They planned to extend sales through the Mitchell Safety Razor Blade Co of America in New York.   

However, R. S. Mitchell died at his home at Dobcroft Road on 11 October 1930, aged 53.  His burial was at Wadsley Church.  He left £1,139.   He was said ‘to be the first man in Sheffield to make a safety razor blade (Sheffield Independent, 7 April 1931).  In 1932, the firm was voluntarily wound up and the plant acquired by the Wafer Razor Co.