Riso printer, risograph, RISO Printer-Duplicator or also called simply only Riso is a stencil printer designed mainly for high-volume photocopying, duplicating and printing. It sits in the realm somewhere between screen print and offset lithography but with a unique aesthetic.
Traditionally, risographs have been used for high volume photocopying in schools, churches and small political parties. It uses soy based inks to produce unique quality outcomes, each screen is made from banana paper and unlike litho printing only takes a single print for the screen to be fully inked and ready for printing.
These days we can see the rise of a risograph printers for its vibrant, environmentally friendly and cost effective nature, especially on medium to large runs. It can produce anything from books to artist prints with tactile finish very similar to that of screen and litho printing, but for a fraction of the cost.
The Risograph is not a high quality print process- it's a cheap, quick and funky alternative to screenprinting that has inherit limitations to output quality. If consideration is taken on the design side (trapping, overprinting, minimizing ink laydown, etc.) many issues will be calmed.
The underlying technology of a risograph is very similar to screen printing or a mimeograph. It works by creating a thermographic master screen for each color of your artwork. This is then wrapped round a rotating drum. Ink is pushed through tiny holes in the screen and onto the paper, which is fed flat through the machine while the drum rotates at high speed to print each image on the paper.
The process works by printing one color at a time. Multicolor images are created by switching the drum color and running the paper through the machine again creating layers in a process similar to screen printing.
The risograph is not perfect like a inkjet or laser printer. The prints will probably look different from what you see on your computer screen. There will be print marks, especially when printing more than one layer or double sided. It is not uncommon in multi-layer prints, or prints with heavy ink laydown to experience roller marks along the leading edge. Luckily, these can be erased easily with a soft eraser. As a general rule, the less ink laydown the better. Full floods tend to have a salty or mottled appearance due to the ink laydown process within the machine and can cause numerous issues if run on the earlier end of the layer build up.
Registration will not be perfect. It is best to assume that mis-registration will happen.
Risograph Printers are not designed for multiple color printing, there will ALWAYS be a degree of mis-registration when printing several colors/ layers at the time, please bare this in mind when designing. Allow bleed and trapping to counter this .Part of the appeal of this process is the slight variation present across an edition- generally the shift tolerance in reg is between 0-2mm
The Machine uses rubber tires to feed the paper into the press. If there is heavy ink coverage already on the page the riso will leave tyre marks on the sheet but these can easily be rubbed off with a rubber.
Double Sided Marks
When printing double sided the feed mechanism will push the sheets together as it feeds the paper, this results in a small mark in the centre of the feed edge again this can be removed with a rubber. If there is particularly heavy coverage the image can smudge slightly as it goes through the press to print the other side.
Max paper size: 11” x 17”
with printable area: 10.5" x 16.5"
Files must be in Illustrator, Photoshop or PDF format. Saved out to 1:1 (5” x 8”, 11” x 17”, etc.) at 300dpi.All images must be at the size intended for printing. The Risograph will automatically convert your images into halftones or grains, so no need to play around with bitmaps.
The best way to deliver files is in layered AI or PSD format, with each layer containing a color separation. Compressed and sent either through email or through an online FTP such as WeTransfer.
All files must be delivered with layers, separations and trapping included, fonts and strokes converted to outlines.
We love helping helping teach our members color separations, trapping and file clean-up
All print work is priced on a custom basis. Please fill out the order form with specs (size, quantity, number of ink colors, etc.) and a digital proof (if possible)
and an estimate will be returned within 24 hours.
Turn times are generally 6-10 business days (depending on quantity) from final artwork receipt.
A digital proof will be delivered for approval pre-printing.
Riso do not make cyan or magenta ink. Risograph printers are limited to a certain number of commercially available colors. It prints using specific spot colors so it is able to print colors that would be unachievable on digital printers, which use CMYK. Beware that color results do vary according to paper stock.
The riso colors are not 100% opaque so they are easily blended to make new colors. As well as blending the 100% tones of the colors, it is also possible to blend any combination of tints together to produce color variants. This is advantage specially when you are planning to use third color that can be easily made out of combing the two colors.
By printing a greyscale image on any one of the color drums you create a monotone, By combining 2 colors you can create a Duotone image.
It is also possible to imitate the CMYK print process by using the colors available. The yellow and black stay the same, we use blue instead of cyan which is slightly darker. and either fluorescent pink or red to replace magenta both give a full color effect but the pink makes a much more vibrant image.
The risograph machine automatically processes greyscale images and applies a halftone screen with customizable LPI and angles. If you desire one type of halftone over another, you need to indicate the LPI number when submitting your job.
If you have a customized halftone screen, or a dither pattern, that you want to apply in printing, the best thing to do is to make your image with that halftone and export it as a 600 DPI Bitmap file. The printer won’t apply any halftone here, and will instead read the custom pattern that you’ve created!
Preferred Maximum Paper Size: 11x17
Printable Paper Sizes: "4x6" up to 12"x18" (Irregular paper sizes can go through the machine)
Paper Weight: 20# text weight (lightest) - 80# Cover weight (heaviest)
Risograph printers can print onto a range of papers but must be uncoated and under 100# cover. There are exceptions though so please contact us to discuss any other options you may have.