Patent ID: 7266335

Claim:
A method of printing a receiving material by feeding the receiving material through a printer containing a first and a second image-forming unit, each of the units including a write head and an image medium, the method comprising forming, by means of the first image-forming unit, a first image on the first image medium using the first write head, forming, by means of the second image-forming unit, a second image on the second image medium using the second write head, transferring, in a transfer nip, the first image to the front of the receiving material and the second image to the back of the receiving material, the two images being brought into register with the receiving material, transversely of the direction of transit thereof, wherein, to obtain said registration: prior to the formation of the said images, a reference position is determined at the transfer nip, the receiving material is fed to the transfer nip in such manner that part of said material which corresponds to the reference position at the said nip substantially coincides therewith, the first image is formed on the first image medium in such manner that part of said image which corresponds to said reference position in the transfer nip substantially coincides therewith, and the second image is formed on the second image medium in such manner that part of said image which corresponds to the said reference position in the transfer nip substantially coincides therewith.