Understanding ink smudges, roller marks, and misregistration
What are ink smudges?
Riso ink dries through absorption. Similar to a newspaper, prints never fully cure.
Rubbing the ink with your finger, even once “dry”, can result in smudging. This is a natural occurrence.
What are roller marks?
Roller marks usually happen in a second or third color pass.
The paper feed rollers pick up color from one print and transfer it to the next print.
What is misregistration?
In Riso printing, each color is printed separately, so colors rarely match up perfectly.
Registration (aligning overlapping colors to form a new image) may shift during a run, and leave small gaps of white between colors.
Design tricks for the Riso
Minimize smudges, roller marks and misregistration using design:
- Set all colors to < 80% opacity (except text).
- Limit your number of colors.
- Four colors at 100% = 400% saturation.
- Leave the top 2” of your image blank, or lightly inked.
- Roller marks tend to happen towards the top and center of a page.
- Avoid large areas of solid colors, color blocks, and designing with a “background-color”.
- It is better to print on a pink piece of paper, than to ink a white piece of paper with pink.
- Use “Trapping” to overlap colors at their edges, decreasing the likelihood of an unwanted white gap.
- Use font size 6pt or higher.
Fixing a finished print
- Riso ink marks can sometimes be removed with light erasing.
- Prints that will be heavily handled (example: book covers) can be sprayed with fixative to help prevent smudging.
For more information on Riso printing, check out our complete Riso Guide.