Is Modal Plastic-Free?
The honest chemistry, the performance trade-offs, and a straight verdict for founders deciding what their next line is actually made of.
Verdict: Plastic-free (with an asterisk)Modal fiber is regenerated wood cellulose, not polyester or nylon plastic. But a modal garment can still contain plastic through elastane, sewing thread, trims, or finishes. Cellulosic fibers can shed during washing; that is different from shedding plastic fibers. For sourcing, check the complete composition and request evidence for the exact fiber grade before extending any biodegradability claim to the finished garment.
What is Modal?
Modal is a type of rayon made from beech wood cellulose, engineered for higher wet strength and a softer hand than standard viscose. Lenzing's branded version is made to a controlled environmental standard. Chemically it is cellulose, the same plastic-free base as cotton and lyocell.
- Fiber type
- Regenerated cellulose (semi-synthetic, plant)
- Source
- Beech tree pulp
- Biodegradable
- Yes
- Sheds microplastics
- No (cellulosic, not plastic)
How is Modal made?
Beech pulp is processed into a cellulose solution and spun into fiber, then given a finishing treatment that raises its wet strength above ordinary viscose. Branded modal is produced in more tightly controlled, higher-recovery processes than generic viscose.
How does Modal perform?
Very soft, smooth, and color-fast, with good drape and better wet strength than basic rayon. It is popular blended with cotton for underwear and tees. It has little stretch on its own and, like all cellulosics, relies on blends for elasticity.
So, is Modal plastic-free?
Plastic-free with an asterisk, same logic as lyocell. The polymer is wood cellulose, not petroleum, so it is not plastic and it biodegrades and sheds no microplastics. The asterisk is that it is a manufactured fiber, so it is semi-synthetic rather than a raw natural fiber. On the plastic question specifically, it qualifies.
Where you see it: Underwear, loungewear, soft tees, and cotton-blend basics.
Does modal shed microfibers when you wash it?
Modal-containing fabrics can shed cellulosic microfibers during washing, so a plastic-free fiber is not a promise of zero shedding. De Falco et al. (2019), Scientific Reports, tested a garment with a polyester front and a cotton/modal back. Its later washes continued to release mainly cellulosic fibers. This was a mixed garment, not a test of pure modal, and it cannot supply a universal shedding rate for modal fabric.
For an intimates program, ask the mill for a shedding test on the actual fabric construction and finish. Keep the fiber composition, test method and wash conditions with the result. A fiber name alone does not establish the finished fabric's shedding performance.
Does a modal fiber certificate cover the finished garment?
No. Evidence for a named modal fiber does not automatically cover a garment made from it. Lenzing identifies TENCEL Modal as regenerated wood cellulose and describes biodegradability certifications for its standard fibers. Its LENZING Modal certification notes explicitly limit coverage to specified fiber types, environments and test conditions, rather than automatically covering a finished product.
Before approving a claim, request the current certificate, the covered fiber grade and evidence relevant to the complete product. Check dyes, finishes, sewing thread and trims as well as the main fabric. Do not turn a fiber certificate into an unsupported claim that the garment biodegrades anywhere.
Is modal with elastane plastic-free?
No. A fabric containing modal and conventional elastane contains a plastic stretch fiber even though the modal portion is cellulose. For a plastic-free brief, require the mill to name every fiber in the blend and check the complete garment specification before approving copy.
Send your composition, construction and stretch requirements to dougie@ohzehn.com for a sourcing spec pack, or review our intimates manufacturing process before booking a call.
| Property | Modal | Polyester | Organic cotton |
|---|---|---|---|
| Polymer origin | Beech tree pulp (plant cellulose) | Petroleum | Plant (cotton cellulose) |
| Is it plastic? | No* | Yes | No |
| Biodegradable | Yes | No | Yes |
| Sheds microplastics | No | Yes | No |
| Process note | Manufactured semi-synthetic, higher wet-strength finish | Energy-intensive, petroleum feedstock | Water-intensive farming |
The OHZEHN-TEX™ take
Modal earns its place for softness in intimates and loungewear. OHZEHN-TEX™ is our own bio-based performance fabric platform: bio-based nylon PA6.10 made from castor oil, with a bio-based stretch fibre made from sugarcane.
Where this fiber lands in production
Modal shows up most in intimates manufacturing and bralette and slip manufacturing, and the standard that governs all of it is set out at fabric manufacturing. The full definition of what counts is at plastic-free fabric.
Frequently asked questions
Is modal a natural or synthetic fabric?
It is semi-synthetic, also called regenerated or manufactured. The raw material is natural (beech cellulose) but it is chemically processed into fiber form. That makes it not a raw natural fiber, but also not a petroleum plastic. It is plastic-free even though it is not strictly 'natural.'
Is modal better than polyester for base layers?
For plastic and microplastic avoidance, yes: modal is cellulose and biodegrades while polyester is plastic that sheds microplastics. Polyester still wins on fast drying and durability, which is the trade a plant-based performance blend is designed to close.
Does modal shed microfibers?
Modal-containing fabrics can shed cellulosic microfibers. A 2019 study of a garment with a polyester front and cotton/modal back found continued release of mainly cellulosic fibers in later washes. It did not test pure modal or establish a universal modal shedding rate.
Is modal with elastane plastic-free?
No. Modal is regenerated cellulose, but conventional elastane is a plastic stretch fiber. A modal and elastane blend therefore contains plastic. Check the full composition, sewing thread, trims and finishes before making a claim about the whole garment.