Macintosh's patented process bonded rubber dissolved in coal-tar naphtha between layers of cloth, producing a genuinely waterproof fabric at industrial scale for the first time. Manufactured in Glasgow and Manchester, the material transformed outdoor clothing, military gear, and later found use lining diving suits and cables, cementing his name as a lasting eponym for the raincoat itself.
Charles Macintosh trained as a chemist in Glasgow and made his early fortune manufacturing dyes and chemicals, including a cudbear dye derived from lichen. His breakthrough came from an unlikely byproduct: naphtha, a waste product of the coal-gas industry, proved an excellent solvent for rubber.
His patent of June 17, 1823, set out the method: rubber dissolved in naphtha, spread between two layers of cloth and pressed together. The resulting fabric repelled rain far more effectively than the oiled fabrics previously used.
Early 'mackintoshes' had a reputation for stiffening in cold weather and becoming sticky in heat, problems later solved by Thomas Hancock's vulcanization refinements. Still, the garment's success was immediate and lasting: British soldiers, sailors, and eventually ordinary pedestrians across the industrializing world adopted the coat, and Macintosh's name entered the English language as a generic term for a raincoat, still used today.
Key people: Charles Macintosh