Abstract: An apparatus for charging a substrate including a dielectric substrate, a support member having a first end and a second end between which the member extends substantially parallel to the substrate, a row of electrodes distributed over the support member between the first and second ends, the electrodes extending from the support member in the direction of the substrate, the electrodes having a free end for spraying a charge on the substrate, each free end having a substantially fixed distance from the substrate, wherein the distance in the case of the electrode located at the first and second end of the support member differs substantially from the distance in the case of the electrode located in the middle of the support member.

Abstract: An ink composition for a meltable ink usable in a printing device in which ink drops are ejected from ink ducts, which comprises agents which reversibly cross-link the ink, the said agents containing a gelling agent. When an ink drop which has been transferred to a substrate passes over into a gel during the cooling process, the consequence is that the viscosity of the melted ink drop increases greatly so that the drops become relatively immobile. In this way the ink drops are prevented from uncontrollably flowing into the paper. As a result, inks of this kind are suitable for use on both porous and smooth substrates. In addition, these inks have been found suitable for use in a printing device in which printed substrates are subjected to thermal after-treatment.