A soft yarn has a story long before it reaches your needles. With modal, that story usually begins with wood.
Turning wood into a fibre suitable for clothing may seem surprising. The connection is cellulose: a structural component of plants, and the material from which modal is made.
Understanding that journey helps explain what modal is, why it is used in textiles, and what to look for when choosing a modal yarn.
What exactly is modal?
Modal is a regenerated cellulose fibre. Manufacturers take cellulose, usually from wood pulp, and process it into new fibres that can be made into yarn and fabric. It belongs to the same broad family of manufactured cellulosic fibres as viscose and lyocell. Textile Exchange: Manmade Cellulosic Fibres
You may see modal described as “semi-synthetic.” The more precise textile term is regenerated cellulose: its raw material comes from plants, but the fibre is formed through manufacturing rather than grown in its final form.
Modal also has a technical definition. It must meet requirements for breaking force and wet modulus—its resistance to a specified amount of stretching when wet. These properties distinguish it from ordinary viscose. BISFA: Fibre Terminology
Is modal always made from beech trees?
Beech wood is closely associated with modal. Lenzing, for example, has a long history of producing modal from beech wood at its Austrian site. Lenzing: Product Portfolio
However, “modal” identifies a fibre type, not a guarantee of one particular tree species. For a specific yarn, look to the supplier’s sourcing information rather than assuming that every modal fibre has the same origin.
How is modal made?
The process can be understood in four stages:
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Prepare the pulp. Wood is processed into cellulose-rich dissolving pulp.
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Make a spinning solution. Chemical treatment using sodium hydroxide and carbon disulfide makes the cellulose suitable for processing.
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Form the fibres. The solution passes through tiny openings into a chemical bath, where cellulose is regenerated into strands.
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Finish the fibres. The strands are stretched, washed, finished and prepared for subsequent processing.
Modal uses a modified viscose process, with adjustments that give the fibres their characteristic wet performance. This is a simplified outline; individual production systems differ. Lenzing: Fibre Technologies
How does the fibre become knitting yarn?
Making fibres and spinning yarn are separate steps.
The prepared fibres are assembled and spun into yarn. They may be used alone or blended with fibres such as cotton. The yarn is then ready for further textile processes, including knitting and weaving.
For a maker, this distinction matters: the fibre is an ingredient, while the yarn has its own construction. Two yarns containing modal can feel and behave differently because of their blend, thickness and twist.
When choosing for a project, check the full composition and yarn specifications, then work a sample in your intended stitch pattern.
Why is modal associated with softness?
Modal is widely used where a soft handle is desirable. Lenzing links the softness of its modal textiles to fibre characteristics including cross-section and tenacity. Lenzing: TENCEL™ Modal
That helps explain its appeal, but softness is also shaped by spinning, fabric construction and finishing. A fine, closely worked fabric and a loose, open knit will not feel identical simply because both contain modal.
Handle the yarn, then wash a swatch according to its care instructions. Notice the surface, movement and dimensions once dry.
Is modal the same as TENCEL?
No. Modal is a fibre type; TENCEL is a Lenzing brand. Its range includes both modal and lyocell fibres.
A yarn labelled “modal” is therefore not automatically made with TENCEL Modal. Likewise, TENCEL does not refer only to lyocell. The full fibre description matters. Lenzing: TENCEL™ Brand
What should you look for beyond the label?
Plant-based raw materials are one part of modal’s story. Responsible sourcing and manufacturing are another.
Useful questions include:
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Is the wood or pulp source documented?
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Is the fibre producer identified?
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Is there information about chemical recovery, emissions and wastewater management?
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Do environmental claims apply to this particular fibre, or only to another producer’s product?
Textile Exchange highlights sourcing as an important consideration for manufactured cellulosic fibres. Lenzing also documents recovery technologies for its own modal production; these should not be assumed to describe every manufacturer. Textile Exchange: Material Sourcing, Lenzing: Modal Production
From understanding the fibre to choosing a yarn
Knowing how modal is made gives you a better starting point for choosing it. You can look beyond a softness claim and ask about the fibre’s source, the blend and the construction of the yarn itself.
Then let your project guide the decision. A washed swatch will help you judge whether that particular yarn offers the feel and movement you want in the finished piece.
Explore our Modal Cotton yarn collection for your next project.