Hancock, Thomas 1786 - 1865

(1786-1865), Inventor

Thomas Hancock was the second son of James Hancock, a timber merchant and cabinet-maker at Marlborough, Wiltshire, where he was born on the 8 May 1786. He was educated at a private school in Marlborough, before moving to London. By 1815 he was in parthership with his younger brother John as a coach builder.

By 1819 he had become interested in the uses of rubber. His experiments to dissolve and manipulate solid rubber began in 1819 and his first patent, of 1820, covered the application of rubber to various articles of dress, to make them more elastic. He eventually made use of thin strips of Pará rubber and produced numerous articles including braces, waistbands and straps at his new factory in Goswell Road. Observing that two freshly cut surfaces of rubber readily adhered by simple pressure, he was led to the invention of the ‘masticator’, as it was afterwards called, in which a roller set with teeth chewed up pieces of rubber and worked them into a plastic and homogeneous mass. The rubber that emerged from the masticator was then pressed into blocks, or rolled into sheets. The masticating process was never patented, but remained a secret in the factory until about 1832, when it was divulged by a workman. Experiments showed that masticated rubber was much more easily acted upon by solvents than ordinary rubber, and this discovery brought Hancock into communication with Macintosh, the well-known manufacturer of waterproof garments, who carried on business in Manchester. In February 1826 Hancock obtained a licence from Macintosh for the use of the patent to produce double-layer fabrics sealed with rubber. Hancock's masticated rubber was better able to dissolve as a strong solution than that of Macintosh, and in 1830 they agreed that Hancock would supply Macintosh with his masticated rubber. Eventually Hancock became a partner in the firm of Charles Macintosh & Co., though he still carried on his own business in London.

Thomas' brother John died of consumption in 1835, leaving nine children. They returned to London and were taken in, educated and provided for by Thomas, who remained unmarried and childless his whole life.

Rubber articles still possessed serious defects due to the material itself; they became sticky, and at low temperatures lost their elasticity. In 1842 specimens of ‘cured’ rubber, prepared in America by Charles Goodyear according to a secret process, were exhibited in England. Hancock investigated the matter, suspected that sulphur was involved, and filed a provisional patent on 21 November 1843. His experiments were successful: he discovered that when rubber was immersed in molten sulphur a change took place, yielding ‘vulcanized’ rubber, which was capable of resisting extremes of heat and cold, and was very durable. He was thus able to submit his specification during the six months allowed by the Patent Office. Goodyear had not applied for a British patent. Hancock also discovered inadvertently that if the vulcanizing process was continued, and a higher temperature employed, a hard substance, known as vulcanite or ebonite, was produced. This material was found to be impervious to chemicals and to be electrically insulating, which made it of considerable value to industry.

Hancock took out sixteen patents in all relating to rubber between 1820 and 1847. He displayed remarkable ingenuity in suggesting uses for what was practically a new material, and the specifications of his patents cover the entire field of rubber manufactures, though many of his ideas were not carried out at the time. In 1857 he published 'Personal Narrative of the Origin and Progress of the Caoutchouc or Indiarubber Manufacture in England’.

He retired between 1842 and 1845, handing over his business interests to his nephew James Lyne Hancock, and the factory continued in production until 1939, having been taken over by the British Tyre and Rubber Company Ltd. He died of heart and kidney disease on 26 March 1865, at Marlborough Cottage, Green Lanes, Stoke Newington, where he had lived for fifty years.