Between the wars, France urgently needed to pave its huge road network in order to prevent rapid deterioration and combat the harmful effects of dust. Black products (first made using tar, later using artificial bitumen) satisfied the two requirements of quality and price.

Bitumen emulsion was tremendously successful very soon, under the name of Colas,which was an abbreviation of COLd ASphalt, and a merger with the Royal Dutch Shell Ltd was necessary to finance this development, which led to the creation of a joint subsidiary, which was given the name of Société Routière Colas.