Electrostatic printing method and its use in rapid prototyping

摘要

A method of copying an image onto a first carrier comprises electrostatic deposition and transfer. First a deposition of fine particle powder is provided on a second carrier by first cleaning a working face of the second carrier, then creating a latent electrostatic image on the working face of the second carrier and finally converting the latent electrostatic image into a real image by transferring a charged layer of fine particle powder to the working face of the second carrier which carries the latent electrostatic image. The real image is then transferred to a first carrier by electrostatic transfer that is characterised in that the transfer is affected by applying to the second carrier an electrostatic charge of the same polarity as that of the charged layer of the fine particle powder, thereby to repel the charged fine powder from the second carrier and onto the first carrier. This method is particularly suited to rapid prototyping whereby a three-dimensional object is built up through the deposition of a plurality of powder layers upon one another and a build plate.