Canvas white pigment and calcium carbonate is rather brittle and susceptible to cracking. As lead-based paint is poisonous, care has to be taken in using it. Various alternative and more flexible canvas primers are commercially available, the most popular being a synthetic latex paint composed of titanium dioxide and calcium carbonate, bound with a thermo-plastic emulsion. Many artists have painted onto unprimed canvas, such as Jackson Pollock, Kenneth Noland, Francis Bacon, Helen Frankenthaler, Dan Christensen, Larry Zox, Ronnie Landfield, Color Field painters, Lyrical Abstractionists and others. Staining acrylic paint into the fabric of cotton duck canvas was more benign and less
Tet (Morris Louis painting) and to artists in New York such as Barnett Newman, Mark Rothko, and Helen Frankenthaler. It was Frankenthaler who created the technique of staining: a process using thinned paint and gravity on an unstretched and untreated canvas. Greenberg admired Frankenthaler’s technique because of his theories on “purism” within the arts. Greenberg believed that painting’s one characteristic which distinguished it from other art forms was its “flatness.” This quality was enhanced by the staining process. The paint actually soaked into the surface of the canvas, showing no three-dimensional qualities. Frankenthaler’s painting "Mountains and Sea" would stand as Louis’s primary influence in