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
Roy Petley of Paris, to his subtle nudes draped with sheets and sunlight. He captures the romanticism of days gone by, with nary a modern automobile or electrical appliance blemishing his canvas. Renowned British art critic, Brian Sewell, described Petley as "a painter who still paints, who brushes watercolour onto paper and oil paint onto canvas, a painter who even settles down to draw the nude from life - an absurdly old-fashioned discipline for an artist to pursue." Petleys is a fine art gallery based in London. It was first known as Petley Fine Art. In October 2003, with his son Jason