An ink builder to build an ink for a hard copy device. The ink has at least one property that deteriorates in storage. The ink builder comprises an ink tank and apparatus for building ink in the ink tank from a plurality of components and/or an ink maintaining apparatus arranged to inhibit deterioration of the at least one property of the ink in the ink tank. The ink builder may be used in cooperation with a separate hard copy device to which the ink tank can be transferred. Methods of producing hard copies using such a hard copy device are also disclosed.