Ejected liquid forms a latent image on a charged transfer surface. In some
invention aspects electrostatic charge is first applied to the surface;
inkjet devices eject the image-forming liquid; voltage is established
between the devices and surface; another, separate substance associated
with the latent image actuates it. In other aspects hydrophobic or
hydrophilic material in the surface stabilizes the image on it;
electrostatic apparatus, associated with the surface, cooperates with the
stabilizing material, further controlling image-droplet position and
size. In other aspects a desired image forms on a final printing medium,
based on an input electronic image-data array; the liquid ejection is
onto an intermediate transfer surface, based on detailed incremental
control by the data, forming a latent image representing the desired
image. An actuating substance, initially discrete from the liquid, is
associated with the image, and a reaction initiated to modify that
substance--which is transferred from surface to final medium.