Laser toner fusion: An imaging process for graphic arts applications

Laser-toner-fusion (LTF) is a dry, high quality electrothermographic imagin g process for producing both monochrome and color images from electronic in put. The process steps involve using a magnetic brush to apply a uniform to ner layer to a substrate imagewise exposing the layer to a high power IR la ser that tacks the toner to the substrate; removing the unexposed toner usi ng a magnetic brush toner removal device, and finally, fixing the image usi ng conventional fusing. The removed unexposed toner can be recycled thereby eliminating waste. The exposed toner particles are partially buried in a t hermoplastic layer and are therefore robust to abrasion. The process is ins ensitive to visible radiation and can be carried out in ordinary roomlights . The energy required for imaging is between 150 and 300 mJ/cm(2). The appl ication most thoroughly investigated is image setting where color separatio ns with 2540 pixels per inch resolution, and with transmission density of 4 .0, have been made to produce high-quality 4-color images.