Pochoir is a refined stencil-based technique employed to create prints or to add color to pre-existing prints. It was most popular from the late 19th century through the 1930’s with its center of activity in Paris. Pochoir was primarily used to create prints devoted to fashion, patterns, and architectural design and is most often associated with Art Nouveau and Art Deco. The use of stencils dates back to as early as 500 C.E. and was also used in Europe from the 1500’s onward to decorate playing cards, postcards and to create simple prints. It was, however, the increase in popularity of Japanese prints in the middle of the 19th century that spurred the refinement of the use of stencils culminating in the development of pochoir. At the peak of its popularity in the early 20th century, there were as many as thirty graphic design studios in France, each employing up to 600 workers.

Pochoir begins with analysis of the composition, including color tones and densities, of a color image. Numerous stencils were designed as a means of reproducing an image. A craftsman known as a découpeur would cut stencils with a straight-edged knife. The stencils were originally made of aluminum, copper, or zinc but eventually the material of choice was either celluloid or plastic. Along with this transition of stencil materials, there was a shift away from the use of watercolor towards the broad, soft, opaque layers of gouache. The technique was further refined in an effort to create the most vivid, accurately colored reproductions. Stencils created by the découpeur would be passed on to the coloristes. The coloristes applied the pigments using a variety of different brushes and methods of paint application to create the finished pochoir print.

Excerpt, http://www.sil.si.edu/ondisplay/pochoir/intro.htm