Yves Klein Trademarked a Color and Painted His Models in It

Yves Klein, a French artist trained as a judoka and obsessed with the color blue, spent the late 1950s trying to find a binder that would suspend ultramarine pigment without dulling its saturation. Conventional oil binders made the color sink into a soft, even gloss; Klein wanted the pigment to look chalky and dry, as if you were looking through a window into pure color rather than at a painted surface. He worked with a Parisian paint supplier named Édouard Adam — whose shop in Montparnasse is still open — until they settled on a polyvinyl-acetate resin sold by Rhône-Poulenc as Rhodopas M, thinned with ethanol and ethyl acetate. The pigment held its raw matte intensity. Klein called the result International Klein Blue.

In May 1960 he filed a Soleau envelope — France's lightweight intellectual-property registration — at the INPI to document the formula and date it. He never pursued a full patent, and the official copy was destroyed in 1965, though Klein retained his stamped duplicate. The legal protection is mostly mythology; the more useful effect was authorship. From 1957 onward Klein produced monochrome IKB canvases, IKB-painted sculptures (including small replicas of the Venus de Milo), and his "anthropometries" — performances in which female models coated in IKB pressed their bodies against canvases while a small orchestra performed his Monotone-Silence Symphony.

Klein died of a heart attack in Paris on June 6, 1962, at thirty-four. He had been working as a publicly recognized artist for less than a decade. The Adam paint shop still sells International Klein Blue, mixed by hand, to customers who walk in off the street.