A composition comprising a homo- or copolymer obtainable by polymerisation of at least one ethylenically un-saturated nitrogen-containing heterocyclic compound and a polyethyleneimine, is suitable for afterclearing a printed or dyed textile material, in particular cotton fibres dyed or printed with reactive dyes. The silicone elastomer of the present invention is ideally suited to a manufacturing environment due to its extended pot life and decreased curing time. A second imaging head with individually addressable channels is operated, either at the same time or a different time, to direct imaging beams to form a second image on the media while scanning over the media along a second scan path. 8 gcm3, and a distance between grains of 30 nm or shorter.