Bromoil printing has the advantage that images are created from bromide enlargements - so 5x4 inch or 8x10 inch internegatives are not required. The bromide print is bleached, leaving behind a faint i [..]

This process was introduced in 1907 by E.J. Wall and eventually replaced the gum bichromate process. Once an enlargement was made on silver gelatin bromide paper, it was bleached in a solution of potassium bichromate to remove the black silver image. Then special brushes were used to apply greasy inks to pigment the surface of the gelatin.