Transparent inks
and overprints

Opaque, translucent, transparent

Inks sit on a scale. An opaque ink hides what is under it; that is why it works on dark garments. A transparent ink carries little or no covering pigment, so the material, or a colour printed before it, shows through. In between are translucent inks. The same colour can come in more than one type, and brands differ, so check the data sheet or ask your supplier. A transparent base or extender turns an opaque ink into a more transparent one.

The rest of this guide assumes you use inks that are clearly transparent and that your material is white or light.

Overprint: two screens, three colours

Print ink A, then ink B over part of it. Where they overlap you get a third colour that neither ink makes alone. Yellow over blue gives green, yellow over red gives orange, blue over red gives purple. With two screens you now have A, B and A+B.

The order matters a little, because no ink is perfectly transparent: the top ink dominates slightly. Test both orders on your material before you commit.

What overprints do for your artwork

• More colours from fewer screens. Two inks give three colours, three inks give up to seven areas. That saves screens, mixing and setup time.
• Depth and shadow. Where a dark tone overlaps a light one, the overlap gets deeper than either. A shadow can be an overlap instead of a separate ink.
• Smooth tints. A halftone of a transparent ink over a solid gives a graded, glowing tone: a soft fade from the base colour into the overprint.
• Forgiving registration. Where two colours meet, letting them overlap slightly hides a small misregistration, instead of a white gap between them.
• A layered look. Overlapping shapes read as layers of glass or tissue paper, a style that is hard to fake with flat colours.

When it does not work

• Dark garments. Transparent ink over dark cloth mostly disappears or turns dark. Switch the lab above to “Dark garment” and see. There you need opaque inks, often on a white underbase.
• Two halftones on top of each other. Dot patterns at the same angle sit on top of each other and either merge or make moiré. Print at most one of the two overlapping inks as a halftone, the other solid.
• Thick layers. Every layer adds ink. Let each layer dry or flash the way your ink system requires before the next goes on.
• Surprise mixes. Two inks you never tried together can go muddy. Print a small test first.

Preparing overprints in PrintFilmReady

PrintFilmReady assigns every pixel of your image to exactly one ink, so it does not create overlaps by itself. That keeps separations clean, but overprints need a different route: one image per ink layer.

1. In your design program, save each ink layer as its own image on the same canvas size: black artwork on white, or the single colour of that ink.
2. Open the first layer in PrintFilmReady, set one ink, choose the same print width for every layer, and generate the film.
3. Repeat for the other layers. Every film has the registration crosses and crop ticks in the same place, so the layers line up.
4. Keep in mind that every layer counts as one job. The free version allows three.

All inks in PrintFilmReady share the same 22.5° halftone angle, so plan solids over halftones, or halftone over solid, rather than two halftones. If you need each ink at its own angle, prepare that outside the tool.

Then mix the colour of each ink with the mixing basics course and print a test.

Testing checklist

1. Print A alone and B alone on the real material, then A+B in both orders.
2. Check the overlap colour in daylight and shop light.
3. Look at the edges: a thin dark line at the overlap means a heavy deposit or the wrong mesh.
4. Write down the order, mesh, squeegee and ink types with the result.

Common questions

We are new, and reviews, testers and ideas make this better. Write a review · Become a tester · Send an idea · Show us your work