Modal fabric is a soft, breathable fabric made from the wood pulp of beech trees. It belongs to the rayon family, along with fabrics like viscose and lyocell. Originally developed in the 1950s, modal has become popular because it feels silky smooth, absorbs moisture well, and stays comfortable against the skin.

In fact, it can absorb around 50% more moisture than cotton, making it a great choice for everyday clothing and warm-weather wear.

Modal is commonly used in underwear, activewear, sleepwear, and other comfortable basics. It is naturally gentle on sensitive skin, resists shrinking and pilling, and stays soft even after repeated washing.

Many premium modal fabrics are made using a closed-loop production process that recycles most of the water and chemicals used, making them a more sustainable option than many conventional fabrics. Compared to standard viscose, modal is stronger, more durable, and better at retaining its shape over time.

What is Modal Fabric?

Modal fabric is a type of semi-synthetic textile produced by chemically processing cellulose extracted from beech tree wood pulp. It is classified within the broader rayon family a group of fibres created from natural cellulose but manufactured using modern chemical processes. What distinguishes modal from other rayons is the high-wet-modulus (HWM) treatment applied during production, which stretches the fibres to create a stronger, finer, and softer material.

The term 'modal' technically refers to a specific type of rayon with defined performance criteria set by the US Federal Trade Commission (FTC): fibres must maintain at least 90% of their dry tenacity after being wetted. This durability standard is what separates modal from standard viscose rayon and makes it a preferred choice for skin-contact garments.

Is Modal Fabric Natural or Synthetic?

Modal fabric is classified as semi-synthetic, also called 'bio-based'. This means its raw material is entirely natural — cellulose derived from beech tree wood pulp — but its production involves a series of chemical processes to dissolve, regenerate, and spin that cellulose into usable fibres. The end product is neither a natural fibre (like cotton, linen, or silk) nor a fully synthetic fibre (like polyester or nylon).

The term 'regenerated cellulose fibre' is the most precise classification. Other fibres in this category include viscose, lyocell (TENCEL™), bamboo rayon, and cupro. Modal sits above viscose and below lyocell in most environmental and performance rankings, with TENCEL™ Modal representing the most sustainable variant within the modal category.

How Is Modal Fabric Made?

Modal production is an evolution of the viscose rayon manufacturing process, with several improvements that produce stronger fibres with a lower environmental footprint. Here is the full process:

Step 1 — Beech Tree Harvesting and Wood Chipping

The process begins in sustainably managed European beechwood forests, primarily in Austria and Central Europe. Beech trees used for Lenzing's TENCEL™ Modal are certified under FSC (Forest Stewardship Council) or PEFC standards, verifying responsible forest management.

The trees are harvested and mechanically reduced to small wood chips.

Step 2 — Cellulose Extraction

The wood chips are cooked under pressure with chemicals to dissolve the lignin (the binding material in wood) and extract pure cellulose. This cellulose is then purified, pressed into sheets, and dried.

The result is a dissolving-grade pulp — a highly refined form of cellulose used as the starting material for modal fibres.

Step 3 — Alkali Cellulose and Spinning Solution

The cellulose sheets are steeped in a sodium hydroxide (caustic soda) solution to produce alkali cellulose.

This alkali cellulose is then reacted with carbon disulfide (CS₂) to form cellulose xanthate, which is subsequently dissolved in dilute sodium hydroxide to create a viscous, syrup-like spinning solution called 'viscose'. At this stage, modal's production shares chemistry with viscose rayon.

Step 4 — Wet Spinning

The spinning solution is forced under pressure through fine, multi-hole metal nozzles called spinnerets into an acidic coagulation bath. As the alkaline spinning solution meets the acid bath, the cellulose regenerates and solidifies into continuous filaments. This wet-spinning process is the core of modal fibre formation.

Step 5 — High-Wet-Modulus (HWM) Stretching

This is the step that makes modal different from standard viscose. The freshly spun filaments are stretched significantly while still in a gel state — a process that aligns the cellulose polymer chains along the fibre axis.

This molecular alignment produces fibres with much higher tenacity (strength), particularly when wet, along with greater fineness and uniformity. It is this HWM treatment that gives modal its superior durability and resistance to shrinkage compared to viscose.

Step 6 — Finishing, Yarn Spinning, and Fabric Construction

The modal fibres are washed, bleached if required, and cut into staple lengths or left as continuous filaments. They are then spun into yarn using ring-spinning or open-end spinning systems.

The resulting yarn is knitted (most commonly into jersey or interlock constructions for clothing) or woven into fabric. Modal's fineness and smooth surface make it particularly well-suited to knitting, which is why most modal garments — underwear, T-shirts, activewear — are knit rather than woven.

Modal Fabric Composition

Pure modal fabric is 100% regenerated cellulose fibre. However, the majority of commercial modal products are sold as blends to enhance specific performance characteristics:

• Modal + Cotton (50/50 or 60/40) — the most common blend; combines modal's softness with cotton's durability and lower cost; ideal for T-shirts and basics
• Modal + Spandex/Elastane (90/10 or 95/5) — adds stretch and recovery; essential for activewear, leggings, and form-fitting underwear
• Modal + Lyocell / TENCEL™ (ProModal, 65/35) — combines modal's softness with lyocell's moisture-wicking strength; used in performance-luxury garments
• Modal + Polyester — adds durability and moisture-wicking capability; used in affordable athleisure blends

Key Properties of Modal Fabric

Modal's commercial success is built on a distinctive combination of properties that most other fabrics cannot match simultaneously:

• Softness: Modal fibres are among the finest of all regenerated cellulose fibres. Their smooth surface and round cross-section create a silky hand-feel that is consistently ranked softer than cotton and comparable to high-quality viscose. TENCEL™ MicroModal, with even finer fibres, is often described as softer than silk.
• Breathability: Modal's open, porous fibre structure allows air to circulate freely through the fabric. This makes it thermally regulating, keeping wearers cool in summer and comfortable in transitional weather.
• Moisture Absorption: Modal absorbs approximately 50% more moisture per unit volume than cotton. This superior absorbency keeps moisture away from the skin and contributes to the fabric's freshness during physical activity.
• Shrink Resistance: Unlike cotton, which can shrink significantly in hot water, modal's HWM-treated fibres maintain dimensional stability through repeated laundering. This is one of the most commercially valued properties of modal.
• Colour Retention: Modal fibres have a high affinity for reactive dyes. The cross-sectional structure of modal fibres allows dyes to penetrate deeply and evenly, resulting in richer colours that resist fading even after many washes.
• Pilling Resistance: The long, smooth fibres in modal create a tight fibre network that resists the surface abrasion that causes pilling a common problem with cotton and viscose blends.
• Drape: Modal has excellent drape characteristics. The fibres are flexible and fine, allowing fabrics to flow and conform to body contours — a property particularly valued in dresses, sleepwear, and lingerie.
• Hypoallergenic: Modal is naturally hypoallergenic and non-irritating to skin. It does not contain the natural waxes, seeds, or proteins found in cotton that can trigger skin reactions in some individuals.

Advantages and Disadvantages of Modal Fabric

Modal fabric is popular for its exceptional softness, breathability, and moisture management, making it a favorite choice for underwear, sleepwear, activewear, and everyday clothing.

However, like any textile, it also has a few drawbacks. Understanding both the benefits and limitations of modal can help you decide whether it is the right fabric for your needs.

Types of Modal Fabric

Modal fabric is known for its softness, breathability, and moisture-wicking properties, making it a popular choice for underwear, sleepwear, and activewear. However, it also has some drawbacks. Knowing the benefits and limitations of modal can help you decide if it's the right fabric for you.

Is Modal Fabric Sustainable?

Modal fabric's sustainability is nuanced and depends heavily on the production source and certification level. Here is an honest assessment across key criteria:

Raw Material: Beech Trees

Beech trees grow naturally in Central Europe without irrigation or pesticides, and the best modal is sourced from FSC or PEFC certified forests in Austria and neighbouring countries. Unlike cotton, beech trees do not require significant supplemental watering, making the raw material stage considerably more water-efficient.

Manufacturing Process

The production of modal involves turning wood pulp into fibers through a chemical process. While this process uses chemicals, some manufacturers have invested in systems that recover and reuse most of the water and chemicals instead of releasing them into the environment.

For example, TENCEL™ Modal uses a closed-loop production process that recycles most of the water and chemicals used during manufacturing, helping reduce waste and emissions.

Certifications

When shopping for modal fabrics, look for trusted certifications and labels such as:

• FSC® (Forest Stewardship Council)
• PEFC™ (Programme for the Endorsement of Forest Certification)
• OEKO-TEX® STANDARD 100
• EU Ecolabel
• TENCEL™ Modal certification

These certifications help verify responsible sourcing, safer manufacturing practices, and product safety.

The Honest Caveat

Not all modal is TENCEL™ Modal. Generic modal from unverified mills may not use closed-loop processes and may fall significantly short of the sustainability credentials associated with Lenzing's certified fibres. When sourcing or specifying modal for sustainable fashion projects, always ask for certification documentation and look for TENCEL™ or Lenzing branding in product descriptions.

Is Modal Fabric Good for Summer?

Yes, modal is one of the most suitable fabrics for summer wear. Its open fibre structure promotes excellent air circulation and passive cooling. Its high moisture-absorption capacity (50% greater than cotton) means that perspiration is drawn into the fibre rather than sitting on the skin's surface.

Combined with its natural softness and lightweight drape, modal delivers comfort in heat and humidity that cotton struggles to match without sacrificing luxury.

For summer applications, look for lightweight modal in the 120–150 GSM range. Modal Air and MicroModal variants offer the highest breathability and are ideal for underwear, camisoles, and flowy summer dresses.

Common Uses of Modal Fabric

Apparel

• Underwear and lingerie: The softness and hypoallergenic properties make modal the fabric of choice for intimate apparel. MicroModal is the premium standard for luxury underwear brands.
• Activewear and yoga wear: Modal's breathability, moisture absorption, and comfortable stretch (especially in modal-spandex blends) make it popular for yoga pants, leggings, and athleisure tops.
• Sleepwear and loungewear: Modal's temperature regulation and silky feel make it ideal for pyjamas, nightgowns, and robes.
• T-shirts and casual basics: 50/50 modal-cotton blends deliver softness and durability for everyday wear.
• Dresses and skirts: Modal's elegant drape creates beautiful silhouettes in flowing dress and skirt constructions.
• Baby clothing: Modal's softness and hypoallergenic properties make it suitable and popular for infant garments.

Home Textiles

• Bedding and pillowcases: Modal sheets offer a silky-smooth surface that becomes even softer with each wash — a popular alternative to high-thread-count cotton.
• Towels: Modal's high moisture absorption and quick-drying properties make it effective for luxury towelling.
• Throws and blankets: Mid-weight modal provides warmth with a lightweight, breathable feel.

Modal vs Cotton

When comparing modal and cotton, there is no single winner because both fabrics have different strengths. Modal is known for its silky softness, excellent moisture absorption, and lightweight feel, making it a popular choice for underwear, sleepwear, and loungewear.

Cotton, on the other hand, is affordable, durable, widely available, and easy to care for. If comfort and softness are your top priorities, modal often comes out ahead. If you need a fabric that can handle everyday wear and frequent washing, cotton remains a reliable choice.

 

Modal vs Viscose

Modal and viscose are both members of the rayon family and are made from plant-based cellulose. While they share many similarities, modal is generally considered the more advanced fiber because it is stronger, softer, and easier to care for. The table below highlights the key differences between the two fabrics.

 

Modal vs Rayon

Modal IS a type of rayon. The term 'rayon' is a generic category covering all regenerated cellulose fibres, which includes viscose (standard rayon), modal, lyocell, and cupro. When people compare 'modal vs rayon', they are typically comparing modal against standard viscose rayon. In that comparison, modal wins on durability, softness, shrink resistance, and environmental performance.

 

Modal vs Polyester

Modal and polyester are very different fabrics designed for different purposes. Modal is made from beech tree wood pulp and is known for its softness, breathability, and comfort against the skin.

Polyester, on the other hand, is a synthetic fibre made from petroleum and is valued for its durability, wrinkle resistance, and performance in sportswear. If comfort and breathability are your priorities, modal is often the better choice. If durability and quick-drying performance matter most, polyester may be more suitable.

 

How to Wash and Care for Modal Fabric

Modal is known for being soft, comfortable, and relatively easy to care for. While it is more durable than standard viscose, following a few simple care tips can help keep your modal garments looking and feeling their best for years.

 

Modal's resistance to shrinkage is one of its most practical advantages. Unlike cotton, which can shrink by up to 10% in hot water, properly cared-for modal retains its dimensions reliably. To preserve modal's softness and silhouette, always wash inside out to minimise friction against other garments.

Where Is Modal Fabric Made?

Modal fabric is produced globally. The most reputable and environmentally certified modal comes from:

• Austria — Lenzing AG is the world's leading modal fibre producer, operating its primary TENCEL™ Modal production in Lenzing, Austria. Fibres are sourced from Central European beechwood forests.
• China — China is a major producer of generic modal fabric and yarn, supplying fast-fashion and mid-market garments globally. Quality and environmental standards vary significantly between Chinese mills.
• India and Indonesia — Growing modal production hubs, particularly for blended fabrics sold into global supply chains.

When sourcing modal for sustainable or luxury applications, specifying Lenzing-certified TENCEL™ Modal and requesting mill certification documentation is essential to ensure environmental and quality claims are met.

How to Identify Modal Fabric

Modal fabric can be identified through several methods:

• Label reading: Garment labels in most countries are legally required to disclose fibre content. Modal will be listed as 'Modal', 'HWM Rayon', or 'TENCEL™ Modal'. If the label reads only 'Rayon' without specifying modal, the fibre is likely standard viscose.
• Touch test: Modal has a distinctly silky, smooth hand-feel that is noticeably different from cotton's slight coarseness. It will feel cool to the touch and flow easily.
• Burn test: Modal burns like other cellulose fibres — it ignites easily, burns with an orange flame, leaves a soft grey/black ash, and smells of burning paper. This is the same as cotton and viscose; the burn test cannot distinguish modal from other rayons.

What is Modal Fabric FAQs

Q1: What is modal fabric?

Ans. Modal fabric is a semi-synthetic, regenerated cellulose fibre made from beech tree wood pulp. It belongs to the rayon family and is known for its exceptional softness, breathability, and moisture-absorption properties. It is approximately 50% more absorbent than cotton and is widely used in underwear, activewear, sleepwear, and luxury basics.

Q2: Is modal fabric natural or synthetic?

Ans. Modal is semi-synthetic, also described as 'bio-based'. Its raw material — beech tree cellulose — is natural, but the manufacturing process involves chemical treatment to regenerate the cellulose into fibres. It is therefore classified as a regenerated cellulose fibre, not a purely natural fibre like cotton.

Q3: Is modal fabric sustainable?

Ans. Modal is relatively sustainable compared to conventional cotton and polyester, particularly when produced by Lenzing AG as TENCEL™ Modal using a certified closed-loop process that recovers 95% of chemicals and water. TENCEL™ Modal holds the EU Ecolabel, is certified biodegradable by TÜV Austria, and is sourced from FSC-certified forests. Generic modal from non-certified mills may not meet these standards.

Q4: Is modal fabric breathable?

Ans. Yes. Modal's open, porous fibre structure allows excellent air circulation, making it one of the most breathable semi-synthetic fabrics available. It is particularly well-suited to warm or humid conditions and is a popular choice for summer clothing, activewear, and sleepwear.

Q5: Does modal fabric shrink?

Ans. Modal is significantly more shrink-resistant than cotton, thanks to its HWM (high-wet-modulus) fibre treatment. Washed in cool to warm water on a gentle cycle, modal garments will typically maintain their dimensions. Exposure to high heat (above 40°C in washing or high-heat tumble drying) can cause some shrinkage.

Q6: How do you wash modal fabric?

Ans. Wash modal on a gentle or delicate machine cycle using cool to lukewarm water (30–40°C / 86–104°F) with a mild, pH-neutral detergent. Avoid bleach, enzyme-based detergents, and high-heat drying. Air drying is preferred; if using a tumble dryer, use a low-heat setting. Modal does not require fabric softener — it maintains its softness naturally.

Q7: What is the difference between modal and viscose?

Ans. Both are regenerated cellulose fibres in the rayon family. Modal undergoes an additional HWM stretching step during production that makes its fibres significantly stronger, softer, more breathable, and more durable than viscose — particularly when wet. Viscose is softer than cotton but weaker when wet, prone to shrinkage, and often requires dry-cleaning. Modal is machine-washable and lower maintenance.

Q8: What is MicroModal fabric?

Ans. MicroModal is a premium, ultra-fine variant of modal fabric produced primarily by Lenzing AG. Its fibres are finer than standard modal, creating a fabric with an even more luxurious, silk-like hand-feel. MicroModal is commonly described as 'the cashmere of knits' and is used in high-end underwear, lingerie, and premium sleepwear. It is 50% more moisture-absorbent than cotton.

Q9: Is modal good for sensitive skin?

Ans. Yes. Modal is naturally hypoallergenic and non-irritating. Unlike cotton, it does not contain natural waxes or proteins that can trigger skin reactions. Its smooth fibre surface is gentle against skin, making it a preferred choice for intimate apparel, baby clothing, and garments worn by people with sensitive skin or conditions such as eczema.

Q10: Is modal fabric vegan?

Ans. Yes. Modal is 100% plant-based, derived entirely from beech tree wood pulp. No animal products or byproducts are used in its production. It is certified vegan by most vegan fashion standards.

Q11: What GSM is best for modal fabric underwear?

Ans. For underwear and intimate apparel, lightweight modal in the 120–150 GSM range is ideal. This weight provides the necessary softness, breathability, and close-to-skin comfort without adding bulk. MicroModal fabrics typically fall in this range. For sleepwear and loungewear, 150–180 GSM modal offers more body and warmth while retaining modal's characteristic softness.

Q12: What brands use modal fabric?

Ans. Many premium basics and activewear brands use modal, particularly TENCEL™ Modal from Lenzing AG. Notable examples include Patagonia, Allbirds, Bread & Boxers, Calida, and Hanro for underwear and basics; numerous luxury sleepwear and loungewear brands source certified modal for their comfort collections. When the fabric is specifically TENCEL™ Modal, Lenzing-licensed hang tags are displayed on the finished garment.