Copying xerography

Selenium is used in Xerography for reproducing and copying documents, letters, etc. It is used by the glass industry to decolorize glass and to make ruby-colored glasses and enamels. It is also used as a photographic toner, and as an additive to stainless steel. 

Just as the growth of xerographic copying and laser-printing, which derives from xerography, was a physicists triumph, the development of fax machines was driven by chemistry, in the development of modern heat-sensitive papers most of which have been perfected in Japan. 

The elegance, cheapness and convenience of xerography for document copying has led to rapid commercial development on a colossal. scale throughout the world. 

Xerography is one of the dominant methods of producing copies of written material. Describe its principle of operation [76, 77]. How are colored copies made ... 

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