grattage
Grattage (literally "scratching", "scraping") is a technique in surrealist painting which consists of "scratching" fresh paint with a sharp blade.In this technique, one typically attempts to scratch and remove the chromatic pigment spread on a prepared support (the canvas or other material) in order to move the surface and make it dynamic. Incorporate the technique of grattage in the painting in order to create a strong sense of texture or pattern on the surface of the picture plane.This technique was used by Max Ernst, Joan Miró, and later by informal artists.
painting technique
painting technique