Alphonse Poitevin

Invention of the process

12 January 2018 michel.momal 0

The light sensitivity of bichromates : In 1797, the chemist Vauquelin, who had just discovered chromium in studying various combinations, found that some of the oxygenated compounds in […]

Imprimerie phototypie

Collotype

12 January 2018 michel.momal 0

Called also photocollographie, héliotypie, albertypie, in German lichtdrûck (printing by the light), in french Phototypie, collotype is a process of high-quality printing, at the fat ink by means of […]