Current printing technologies such as ink-jet and electrostatographic printing, allow for very high quality output of both images and text. Electrostatographic processes and apparatus employ the use of toners, which are generally comprised of a resin and a colorant, along with other desirable additives like charge control agents. In general, a desired image is transferred to an organic photoconductor (OPC) coated drum or belt in the form of a charged pattern representing the image. Toner is then electrically attracted to the charge on the drum and adheres to the drum. Lastly, the toner is transferred to an image-receiving substrate (typically paper) and fused onto the substrate, resulting in permanent image formation on the substrate.
In the present art, it has been difficult to obtain a uniform glossy finish on the printed product. If, for example, a colored graphical image is printed on glossy paper but the image forming agent is not absorbed into the paper, the perception that one is looking at photograph is not obtained. Another example is in the electrostatographic area; using currently-available toners, a uniform glossy or even matte finish printed product cannot be obtained, except when special coatings applied to the print, or equipment for the same, are used. Since such additional process steps add cost, bother and time to the printing process, they are undesired. Even if a conventional glossy finish substrate such as transparent overhead material is used for printing, a uniform glossy image is surprisingly not obtained; the characters or image comprising the fused toner can still be made out from the rest of the otherwise glossy finish when one looks at the substrate off-angle. This becomes more apparent once one considers that the fused toner only sits on the surface of the glossy substrate.
Glossy electrostatographic prints, on regular or synthetic paper, e.g., Tyvek (DuPont trademark)-type materials, have long been desired. The advent of high speed, high resolution digital color electrostatographic printers such as those from Xeikon NV (Mortsel, Belgium) or Agfa Division of Bayer Corporation (Wilmington, Mass.) have made it possible for photographic digital images that are comparable in quality to silver halide-derived images to be made quickly and with great versatility. One drawback to obtaining customer acceptance of this new medium, however, is the unavailability of a glossy print generated from a digital photographic image that resembles the prints available from the photo lab. The glossy finish of such prints is well-known to enhance the intensity of the color image. If similar quality glossy prints could be made with, e.g., high speed digital color electrostatographic imaging systems using a simple substrate material requiring no additional treatment or equipment, other than feeding the material into the printer, it is believed that consumer and industry acceptance of this technology would increase greatly.