French lacquerware artists of the period of Louis XV. The four brothers—Guillaume (d. 1749), Julien (d. 1752), Robert (b. 1706—d. 1765), and Étienne-Simon (d. 1770)—are remembered for perfecting the composition and application of vernis Martin, a lacquer substitute named after them, patented by Guillaume and Robert in 1730. In 1748 their factory became part of the Royal Factory of Furnishings to the Crown. Among their commissions were coaches and rooms at Versailles. Their name is also associated with vernis Martin fans, although it is not known if they actually made these fans. Robert's son Jean-Alexandre (b. 1738) worked for Prussia's Frederick II the Great at Potsdam.