Speedball Opaque Fabric Screenprinting Inks are ideal for use on dark fabrics, paper or cardboard (not for use on nylon). Washfast when properly heat-set. Non-flammable, no solvents and no offensive smell. AP Non-toxic; conforms to ASTM D-4236. These iridescent opaque colors can be screenprinted or painted on with brush and cleans up easily with water. Archival qualities.