What is Riso?
Risograph is a type of duplicator developed in 1980’s Japan by Riso Kagaku Corporation. Designed as a successor to mimeograph they were built with the intention of fast and low cost duplication. In this area they are extremely effective with the ability to print anywhere from 20 to 5000 copies in a matter of minutes. Initially Risograph duplicators were marketed towards offices, schools and government bodies as these features made them a much cheeper alternative to most commercially available printing options.
In the last decade Risograph has seen growing popularity within the artistic and design community due to its unique palette of spot colours and tactile print quality. The Risograph is also one of the most environmentally sustainable forms of print; using a soy based ink it is completely solvent free, uses a fraction of the electricity needed for laser or digital printing. To further this ends we only use paper that is 100% recycled from post-consumer waste so as to ensure the most eco-friendly print solution available.
Yalla Riso is a new printing service based in Dundee Scotland. We do all of our printing with a 20+ year old Risograph RP3700.
How does it work?
Risograph is usually described as a combination of screen printing, photocopying, and offset printing. The images are made through being burnt onto a stencil (referred to as a master) which is wrapped around a cylinder coated with ink (referred to as a drum). The drum turns and paper is fed into the machine, much like screen printing, the ink only passes through the areas of the master that the image is burnt into and crates a print. Whenever a new colour is used a new master has to be made and a separate layer is printed on the existing ones.
What files do you Require?
Please provide high resolution (300-600 dpi) grayscale PDFs - one for each color used in your project. The Riso will convert the gray values to halftones, so no need to do that ahead of time. If your project is full-bleed, include at least an 5mm bleed area either embedded in the file or otherwise indicated. For booklets or zines provide your project in reading order and we will find the most economical print layout.
We are also able to print a faux-CMYK using Medium Blue, Fluoro Pink, Yellow and Black. As these are not exact process spot colours there will be a certain degree of variation so please feel free to consult with us prior to printing.
If you require more hands on support with your project we are happy to help you prepare your files at any stage for printing at an hourly rate.
It is worth remembering that much like screen printing the colours are printed in individual layers. Each of these has a degree of opacity so two layers where colours overlap can be used to produce new combinations of blended spot colours.
Given the, at times, fickle nature of riso printing and the age of the machine we use there is an inevitability in inexactitude. The process is not as straightforwards as hit print and wait, but is far more of a collaboration between artist, printer and the riso itself. These imperfections have always been part of the appeal of Risograph and hold it unique to all other forms of printing.
That said, considered design can minimise a number of these issues. By avoiding 100% fills over the entire page (especially in the centre) can reduce roller marks on the paper. Trapping around separate colours can also help to hide small misregistrations that may occur when working with more colours.