Xerographic copier

Charge-transfer polymers were commercialized by IBM Corporation since about 1968 in xerographic copiers A drum covered by trinitro-fluorenone-polyvinyl carbazole polymer mixed with trinitrofluore-none replaced the expensive Se drum. 

The first major commercial application of amorphous semiconductors was as the photoreceptor in xerographic copiers and subsequently in laser printers. The early photoreceptors were selenium films, but several other materials were subsequently developed, including ASgSCg and various organic films. Amorphous silicon is a good material for a xerographic photoreceptor (e.g. Shimizu (1985), Pai (1988)) and is used in some commercial copying machines. 

Figure 5 A schematic of the first xerographic copier, described in a patent issued to Carlson in 1944.

Greek for dry (xeros) and writing (graphos). The process was invented in 1938 and patented in 1940 by Chester F. Carlson and involves several different physical phenomena. At the time the invention was first made these processes were poorly understood and the first demonstration copies were not of the quality we are used to today. Carlson demonstrated his invention to twenty American companies and generated an enthusiastic lack of interest . Nevertheless, development was undertaken initially by the Battelle Memorial Institute and subsequently by the Haloid Company, now known as the Xerox Corporation. The first commercial xerographic copier appeared on the market in 1959 and is today a worldwide multi-billion pound industry. 

Figure 1. Schematic of typical xerographic copier. Process elements are r...

In many cases it is possible to coat a metal object with a layer of PTFE to meet the particular requirement. Nonstick home cookware is perhaps the best-known example. PTFE is used for lining chutes and coating other metal objects where low coefficients of friction, chemical inertness, nonadhesive characteristics are required. The same properties make PTFE useful for coverings on rollers in food processing equipment, xerographic copiers and saw blades, coatings on snow shovels, and many other similar applications. The Alaskan oil pipeline, for example, rests on PTFE-coated steel plates. Most new bridges and tunnels use similar supports. 

Major Applications Image producing materials, recording materials,10-12 resist composition,i3 xerographic copier materials,i4 inks,i5 cleaners,io cosmetics,i dental adhesives.i ... 

Kosche, H. H. Markable and correctable xerographic copier material. Ger. Offen. DE 3042296, 1982 Chem. Abstr. 1983, 98, 25496. 

In this case, microscopic tendrils of dye appear at the edge of the dot giving it and the overall print quality a blurred effect. This is particularly serious in the case of text printing, which benefits most from sharp dot edges. Feathering is common for papers used in xerographic copiers. Bond paper, which is a popular office stock, is a partially coated paper and exhibits little feathering. 

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