Risograph is a high-speed digital printing system manufactured by the Riso Kagaku Corporation and designed mainly for high-volume photocopying and printing. Increasingly, Risograph machines have been commonly referred to as a RISO Printer-Duplicator, due to their common usage as a network printer as well as a stand-alone duplicator. When printing or copying multiple quantities (generally more than 20) of the same original, it is typically far less expensive per page than a conventional photocopier, laser printer, or inkjet printer.
The underlying technology is very similar to a spirit duplicator. The original is scanned through the machine and a master is created. This master is then wrapped around a drum and coated with a thin layer of ink. The paper runs flat through the machine while the drum rotates at high speed to create each image on the paper. This simple technology is highly reliable compared to a standard photocopier and can achieve both very high speeds (typically 130 pages per minute) and very low costs.
For schools, clubs, colleges, political campaigns and other short run print jobs, the Risograph bridges the gap between a standard photocopier (which is cheaper up to about 50 copies) and a commercial printer (cheaper over about 10,000 copies).
Risographs have typically had interchangeable colour inks and drums allowing for printing in different colours or using spot colour in one print job.
The latest Riso model, the HC 5500, uses a high speed ink-jet technology to achieve full (4) colour at 120 pages per minute.
List of Risograph models
This is a partial list of models, specifications and consumables - a work in progress. Note this does not exist elsewhere on-line !
* Riso Worldwide Official Site http://www.riso.com
* RISO USA, Canada, Mexico, and Latin America http://us.riso.com
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