Lyocell (often sold under the brand name Tencel) should be ironed on low heat, no higher than 110°C/230°F, with the garment turned inside out and steam turned off. That’s the short answer. The longer answer involves understanding why this fabric is more heat-sensitive than cotton and how to avoid the shiny marks and stiffness that come from getting it wrong.
The Right Temperature Setting
Set your iron to its lowest setting, typically labeled “silk” or “synthetic” on the dial. The maximum safe temperature for lyocell is 110°C (230°F). For context, cotton is usually ironed at nearly double that. Lyocell fibers begin to physically shrink between 130°C and 160°C, and above 170°C the fiber surface starts to break down visibly. So the margin between “safe” and “damaged” is narrower than you might expect if you’re used to ironing cotton or linen.
Turn off the steam function. While lyocell loves moisture in general, steam from an iron delivers heat and water at the same time in concentrated bursts, which can leave water spots or push the fabric past its comfort zone in localized areas.
Iron It Slightly Damp
The easiest way to get wrinkles out of lyocell is to iron it while it’s still slightly damp from washing. Pull the garment out of the wash or off the drying rack before it’s fully dry, and the residual moisture helps wrinkles release at a lower temperature. If the garment is already dry, lightly mist it with a spray bottle of plain water and let the moisture absorb for a minute or two before you start.
This approach works because lyocell fibers respond well to moisture. The internal hydrogen bonds in the fiber loosen when wet, making the fabric pliable and easier to smooth flat. As it dries under the warmth of the iron, those bonds re-form in the new, wrinkle-free position.
Flip It Inside Out and Use a Pressing Cloth
Always iron lyocell on the reverse side. Direct contact between a hot iron and the face of the fabric creates shiny patches called “glazing.” These happen because heat compresses and flattens the fiber surface, changing the way it reflects light. On dark-colored lyocell, these marks are especially noticeable and can be permanent.
For extra protection, place a thin cotton cloth (a clean handkerchief, a piece of muslin, or a flour-sack towel) between the iron and your garment. This buffer, called a pressing cloth, absorbs some of the direct heat and distributes it more evenly. It’s a small step that makes a real difference, particularly on garments you care about.
Keep the Iron Moving
Never let the iron sit in one spot. Concentrated heat in a single area creates permanent shine marks on lyocell’s surface. Move the iron in smooth, steady passes. You don’t need to press hard. The combination of low heat, slight dampness, and gentle pressure does the work. Pressing down aggressively just increases the risk of glazing.
If you hit a stubborn wrinkle, make several light passes rather than holding the iron still. Patience at low heat always beats brute force at high heat with this fabric.
Why Lyocell Is More Delicate Than Cotton
Both lyocell and cotton are cellulose-based fibers, but they’re structured differently. Lyocell fibers start losing internal stability at surprisingly low temperatures. Research using infrared spectroscopy has shown that the hydrogen bonds holding lyocell fibers together begin weakening at temperatures as low as 70°C to 80°C. Those bonds do re-form around 130°C, but by that point the fiber is also starting to shrink. Push the temperature higher and the fiber’s crystalline structure, essentially its internal scaffolding, degrades progressively. Above 150°C, the fibers become increasingly fluid and weak. Strength, elasticity, and color all deteriorate.
Cotton, by comparison, can tolerate temperatures up to about 140°C for extended periods without meaningful damage. That’s why your cotton shirts can handle a hot iron and your lyocell blouse cannot.
What Heat Damage Looks Like
Mild heat damage on lyocell shows up as a persistent sheen or stiffness in the area that was overheated. The fabric may feel slightly papery or lose its characteristic drape. Discoloration, typically a yellowing or browning, indicates more serious damage where the cellulose has started to chemically break down, forming new compounds on the fiber surface.
Unfortunately, heat damage to lyocell is not reversible. Unlike a scorch mark on cotton that you can sometimes lighten with a wash, structural changes in lyocell fibers are permanent once the crystallinity is lost. Prevention is the only reliable strategy.
Alternatives to Ironing
If you’d rather skip the iron entirely, lyocell responds well to a few other approaches. Hanging the garment in the bathroom while you shower lets the ambient steam relax wrinkles gently. A handheld garment steamer on its lowest setting, held a few inches from the fabric, works well too, just keep it moving and don’t saturate the fabric.
The simplest trick is to reshape the garment while it’s still damp from washing. Smooth the fabric flat with your hands, gently tug seams straight, and hang or lay it flat to dry. Lyocell has a natural drape that cooperates with gravity, and many garments will dry nearly wrinkle-free if you catch them at the right moment. For lyocell blends (which often include cotton, polyester, or elastane), this works slightly less well, but it still reduces the need for ironing significantly.