Yes, you can dye lyocell. It’s a cellulose fiber made from wood pulp, which puts it in the same chemical family as cotton, rayon, and linen. Any dye that works on cotton will work on lyocell, often with even better color absorption. Lyocell actually takes up nearly twice as much dye as cotton under identical conditions, so you can expect rich, vibrant results.
Which Dyes Work on Lyocell
Fiber reactive dyes (sold under brand names like Procion MX) are the gold standard for lyocell and all cellulose fibers. They form a permanent chemical bond with the fiber rather than just sitting on the surface, which means the color holds up through washing. Dharma Trading Co. lists Tencel (the most common brand name for lyocell) alongside cotton, rayon, hemp, and linen as ideal candidates for their fiber reactive dyes.
You can also use direct dyes and all-purpose dyes like Rit, though these produce less permanent results and fade faster over time. If you want the best colorfastness and brightness, fiber reactive dyes are worth the slightly more involved process.
Natural Dyes
Lyocell takes natural dyes well, but you’ll need a mordant to lock the color in. Research on lyocell dyed with marigold extract tested five different mordants and found that iron (ferrous sulfate) produced the deepest color. Alum, tin, and copper also work. The mordanting process involves soaking the fabric in a mordant solution at around 190°F (90°C) for about 30 minutes, either before or after dyeing. A 4% mordant concentration relative to fabric weight is a standard starting point.
How to Dye Lyocell at Home
The process is essentially the same as dyeing cotton with fiber reactive dyes. You’ll need the dye, salt (to push the dye into the fiber), and soda ash (to fix it permanently). Here’s the general approach:
- Pre-wash the fabric to remove any finishes or sizing that could block dye absorption. Use hot water and a textile detergent or plain dish soap.
- Dissolve the dye in warm water, then add it to your dye bath. For tub dyeing, use enough water that the fabric can move freely.
- Add salt to the dye bath. Around 30 to 40 grams per liter is the range used in research on lyocell. For a home setup, that’s roughly one cup of salt per gallon of water.
- Add soda ash after the fabric has soaked in the dye and salt solution for 15 to 20 minutes. About 8 to 10 grams per liter is typical. This is the step that triggers the chemical bond between dye and fiber.
- Let it soak for at least an hour, stirring occasionally. Longer soak times (up to overnight for cold-water methods) deepen the color.
- Rinse thoroughly in cool water, then warm water, until the water runs clear. A dye fixative applied after rinsing can improve wash fastness further.
You can dye lyocell in a bucket, a plastic tub, or a washing machine. Tie-dye and hand-painting techniques with fiber reactive dyes also work beautifully on this fiber.
Temperature and Shrinkage
Lyocell shrinks when processed in hot water, though not dramatically. Industrial testing found residual shrinkage of about 2.5% lengthwise and 1.3% widthwise after wet processing. For a home project, that means a garment could shrink slightly, especially if you use warm or hot dye baths. Pre-washing in the hottest water you plan to use during dyeing helps minimize surprises.
Cold-water dyeing (room temperature, around 70°F) is perfectly effective with fiber reactive dyes and reduces the shrinkage risk. You just need a longer soak time to compensate.
Watch for Fibrillation and Pilling
Lyocell has one quirk that sets it apart from cotton: it fibrillates easily. That means the outer layer of individual fibers can split into tiny hairlike strands during wet processing, especially with agitation. This gives the fabric a fuzzy or slightly peach-fuzz texture and can lead to pilling over time. Of the common cellulose fibers, lyocell shows the lowest pilling resistance after dyeing.
To minimize this, handle the fabric gently during dyeing. Avoid wringing or aggressive stirring. If you’re using a washing machine, choose a gentle cycle. Research also found that certain dye types help: dyes that form more cross-links with the cellulose (polyfunctional reactive dyes) slightly improved pilling resistance compared to simpler reactive dyes. For home dyers, this isn’t something you can easily control by dye brand, but gentle handling makes the biggest difference.
How Well the Color Holds
Fiber reactive dyes on lyocell produce excellent colorfastness because the dye bonds chemically with the cellulose. The color won’t bleed or fade significantly with normal washing. That said, proper rinsing after dyeing is critical. Any unfixed dye left in the fabric will bleed in the first few washes and stain other clothes. Rinse until the water is completely clear, and consider using a commercial dye fixative as a final step.
For natural dyes, colorfastness depends heavily on your mordant choice. Iron mordants produce the most wash-resistant results on lyocell, while unmordanted natural dyes will fade quickly. Even with a good mordant, natural dyes on any cellulose fiber are less permanent than synthetic fiber reactive dyes.
Lyocell Blends
Many garments labeled as lyocell or Tencel are blended with other fibers. A lyocell-cotton blend will dye evenly since both fibers are cellulose, though the two may absorb slightly different amounts of dye. Lyocell blended with polyester or elastane is trickier: the synthetic fibers won’t absorb fiber reactive dyes, so you’ll get a lighter or heathered effect where the synthetic threads remain closer to their original color. A lyocell-elastane blend will still dye well overall since the lyocell portion absorbs dye eagerly, but check your garment’s fiber content before you start so you know what to expect.