Risograph
A Risograph is a Japanese stencil printer that prints one spot ink per drum. How its master is burned, why fluorescent pink outshines a screen, and its revival.
What is a risograph?
A Risograph is a high-speed stencil printer made by the Japanese company Riso Kagaku, and riso has also become the name for the look of its prints: flat spot colors, visible grain and layers that sit slightly out of line. It looks like a big photocopier, yet it works more like a screen printing press.
Riso means ideal in Japanese. The company grew out of a mimeograph printing business that Noboru Hayama started in Tokyo in 1946.
How does a risograph print?
The machine scans the original, and a thermal head burns thousands of tiny holes into a thin master sheet, one for each dot of the image. The master wraps around a drum full of ink, and as paper passes under it the ink is pressed through the holes. Once the master exists, each copy costs little more than paper and ink, and the fastest machines print well over 100 pages a minute.
Each drum holds one color. A two-color print needs two masters and either two passes through the machine or a model with two drums, and each pass lands a fraction of a millimeter differently. That is where riso's famous misregistration comes from.
Why do riso colors look so bright?
Riso inks are spot colors, mixed in advance instead of built from cyan, magenta, yellow and black dots. The fluorescent ones absorb ultraviolet and blue light and give it back as pink or orange, so Fluorescent Pink can look brighter than the white paper around it.
A monitor can't show that glow, since it can only light red, green and blue pixels. Every digital riso mockup is a stand-in, and the fluorescent inks always come out more intense on paper than on screen.
The inks are soy based and dry by soaking into the sheet. That is why riso favors uncoated paper, and why a fresh print can still smudge under your thumb.
Why did artists adopt the risograph?
Schools, churches and offices bought these machines for decades to run off newsletters and worksheets. As those buyers moved to laser printers, used machines got cheap, and independent presses, zine makers and art schools took them over.
Riso also fills a gap that offset printing covers badly: runs of a few hundred to a few thousand copies in bright colors at a low cost per sheet. An earlier Riso product, Print Gocco, a small home screen printer that went on sale in 1977, had a similar cult following among illustrators making cards and small prints.
Making the riso look
The Risograph Effect simulates one to six drums. Its Pink + blue preset uses the published colors of real Fluorescent Pink and Blue riso inks. Raise Misregistration from 2.5 to about 4 for a print that clearly went through the machine twice, or pick the Black + yellow preset, with its coarser Size of 12, for a cheap gig-poster feel. Push Ink spread up a little when the result looks too crisp, because real riso dots swell as the ink sinks into uncoated paper.
