How to Achieve Vivid, Long-Lasting Colors in SLS 3D Printing

Although many still associate 3D printing with single‑colour parts, achieving vibrant, full‑color SLS prints has never been easier. In this tutorial, we explore proven methods to produce vivid, durable colors for prototypes and production parts.

Colouring SLS parts can be done during post‑processing, and the optimal method depends on the part’s intended use—whether it’s a demonstration prototype or a fully functional production component—as well as the desired finish and color palette.

Painting or spraying

This straightforward approach applies acrylic paint—or, increasingly, cellulose or oil‑based paints—directly to the finished part. Because paint is mixable, you can create virtually any hue on demand. However, compatibility matters: some SLS polymers accept paint better than others and may need surface prep, such as sanding and priming for nylon. Always remove residual powder before coating. While the technique offers limitless color possibilities, complex geometries can make hand‑painting time‑consuming; tools like Dyemansion’s Powershot C can speed up the process.

Keep in mind that any coating will alter the surface texture. For functional parts, a matte finish might be preferable, whereas a glossy look could be desired for visual models. Adjust your finishing choice accordingly, as it can also affect dimensional accuracy.

Dyeing

Dyeing immerses the part in an acid‑based solution, after which a fixative and finish are applied. Unlike painting, dye penetrates the material, so complex geometries are handled uniformly and dimensional integrity is preserved. The result is a scratch‑resistant, long‑lasting finish, especially suitable for porous SLS grades that absorb dye readily. The trade‑off is that dyes do not produce glossy highlights, so a separate topcoat is required if a high‑gloss appearance is needed.

Printing with coloured materials

Printing directly with colored SLS powders eliminates post‑processing steps, but the market remains niche. Sandstone‑based full‑color systems exist, yet they yield hard, brittle parts unsuitable for production. Advanced printers such as the Projet 660 can handle colored powders, but the technology is still maturing, and research into new colorants is ongoing. For now, FDM printers with a wide range of colored filaments remain the most accessible full‑color solution—covered in depth in a forthcoming tutorial.

Maximising your colours’ durability

To keep colors vibrant, choose the right finish. A hard lacquer not only provides UV protection—preventing sun‑induced fading—but also boosts surface hardness. Such coatings are typically applied in thick layers, so balance aesthetic appeal with mechanical performance. Selecting the correct topcoat can extend the life of your colored SLS parts without compromising function.