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  • Writer's pictureValinda

What is Modal Fiber - A Comprehensive Guide to the Eco-Friendly Elegance

Unlocking the secrets behind the softness, versatility, and eco-conscious allure of fabrics, our latest blog post delves into the fascinating world of modal fiber. Derived from natural cellulose, typically sourced from beechwood trees, modal has emerged as a sought-after material in the textile realm. In this exploration, we unravel the intricate process of creating modal fiber, its unique properties that make it a favorite among fashion enthusiasts, and its impact on both comfort and sustainability. Join us as we navigate the threads of modal, uncovering the reasons why this fabric is making waves in the world of fashion and beyond.

Modal Fiber Definition

Modal was at first introduced by Lenzing AG Company of Austria who trade named the fabrics identity. Modal fiber refers to a type of regenerated cellulose fiber, similar to viscose or rayon. It is produced from beechwood trees, primarily using a process called the "modal process." The modal process involves treating the cellulose obtained from the wood pulp with a specific type of chemical and then spinning it into fibers.

red modal fiber

How is Modal Fiber Made?

The manufacturing process of modal fabric closely mirrors that of viscose rayon, with modal serving as an upgraded version that addresses some of the most wasteful and environmentally harmful aspects associated with viscose production.

Harvesting and Processing Cellulose

  • Beech trees are harvested to obtain cellulose for modal fabric.

  • The trees are broken down into small chips, roughly the size of postage stamps.

  • The chips undergo a purification process to extract cellulose, with the remaining tree components being discarded.

Formation of Cellulose Sheets

  • The extracted cellulose is shaped into sheets.

  • These sheets are immersed or "steeped" in vats of sodium hydroxide (caustic soda), with modal rayon using lower concentrations than viscose rayon.

Crumbs Creation and Carbon Disulfide Immersion

  • Sheets are broken down into crumbs without undergoing an aging process.

  • The crumbs are directly immersed in carbon disulfide, turning them into sodium cellulose xanthate. At this point, the cellulose loses its purely organic nature.

Syrupy Solution and Spinneret Process

  • Sodium cellulose xanthate is immersed in caustic soda again to create a syrupy solution.

  • The syrupy substance is immediately forced through a spinneret to form fibers.

Fiber Treatment and Yarn Formation

  • Fibers undergo immersion in sulfuric acid, followed by stretching and transformation into yarn.

Yarn Processing

  • The yarn undergoes washing, bleaching, rinsing, and drying processes.

  • The dried yarn is loaded onto spools, ready for subsequent treatments like pre-shrinking, fire resistance, or wrinkle resistance.

Fabric Weaving

  • The prepared modal yarn is woven into a fabric.

blue modal fiber

What is in Modal Fabric?

Modal fabric is made from cellulose fibers, which are derived from beechwood trees. The process of converting the cellulose into modal fabric involves several steps (see above). There are several chemicals used during the production of modal including exposure to sodium hydroxide (caustic soda), carbon disulfide and bleach

Modal is often mixed with cotton to enhance the breathability of the fabric or spandex to enhance the stretchiness and flexibility of the fabric. 

What is Modal Fabric Used for

Modal is frequently used as a substitute for silk or cotton. Originally conceived as an alternative to silk, early iterations were coined "artificial silk" and gained popularity in scarves and nightwear until their flammability became apparent.

Modernized versions of modal, including modal rayon, are often used as silk alternatives. However, it is more prevalent to encounter modal rayon blended with silk rather than finding scarves and similar items crafted entirely from rayon.

Modal rayon, valued for its softness, thinness, and breathability, is particularly favored in sportswear. It is a common choice for yoga pants, bike shorts, and even swimwear. Recognized for its effective sweat-wicking properties, easy cleaning, and unexpected durability, modal rayon stands out as a lasting material.

gold modal fiber

Is Modal Fabric Toxic?

Modal fiber itself is not considered toxic. Modal is derived from natural cellulose, typically obtained from beechwood trees. The process of turning this cellulose into modal fiber involves several chemical treatments, but the finished product is generally considered safe for use in textiles.

However, it's essential to note that the manufacturing process does involve the use of chemicals like sodium hydroxide and carbon disulfide. These chemicals can be harmful if not handled properly during production. Strict regulations and safety measures are typically in place in manufacturing facilities to minimize the risk to workers and the environment.

For consumers, finished modal products are generally considered safe when used as intended. It's crucial to follow care instructions provided by manufacturers to maintain the fabric's properties and minimize any potential risks associated with the chemicals used during production. If you have specific concerns or sensitivities, it's always a good idea to check with the manufacturer or choose products from reputable brands that prioritize safety and environmental considerations.

black modal fiber

What is the Environmental Impact of Modal

The production of modal fabric exhibits a somewhat improved environmental profile compared to the manufacturing process of viscose rayon. This environmental advantage primarily stems from the reduced concentrations of caustic soda used in dissolving and purifying the cellulose required for modal fabric production.

Nevertheless, the modal fabric manufacturing process incorporates a step known as "xanthation," involving the application of carbon disulfide to cellulose during production. Carbon disulfide is a notorious neurotoxin released into the environment through air emissions and contaminated water produced during the rayon manufacturing process.

Once introduced into the ecosystem, carbon disulfide poses a threat to animal life in the vicinity of factories or waste stations and can lead to severe health problems in humans. Those most at risk are the workers involved in modal fabric production, facing potential harm such as liver and kidney damage, blindness, psychosis, coma, or even death upon exposure to this toxic chemical.

In recent years, rayon manufacturers have implemented measures to mitigate the impact of carbon disulfide on both workers and the environment. Solutions such as chemical scrubbers in factories and absorption machines to trap carbon disulfide before it reaches workers or the surrounding ecosystem have been adopted.

The environmental sustainability of acquiring cellulose for rayon depends on the cultivation and harvesting processes employed. Many rayon manufacturers exclusively use cellulose from trees grown on land unsuitable for other agricultural purposes. Certain types of wood, such as bamboo, are considered more environmentally sustainable than others.

However, a significant concern remains – the substantial waste generated from harvesting tree material for rayon production. Only the cellulose from trees is utilized in making this fabric, with the remaining tree material discarded, highlighting a challenge in the overall sustainability of the modal fabric production process.

pink modal fiber

Modal Fabric Pros and Cons

Modal is an amazing fabric with lots of advantages. 


  • Stretchy. Modal’s flexibility makes it ideal for items like t-shirts and athletic wear.

  • Soft. Modal l has an incredible soft touch, and is often used for bed sheets,pajamas and undergarments.

  • Breathable. Modal is great for sports clothing and everyday clothes because the fabric’s weave is very breathable.

  • Water absorbent. Modal is 50% more absorbent than cotton; micropores inside the fabric absorb any water or sweat they come into contact with.

  • Drapes well. Similar to rayon and other silk alternatives, modal has a beautiful drape that makes it ideal for clothing and decoration.

  • Doesn’t pill. The fabric resists pilling and has a smooth finish that makes it ideal for everyday wear and use.

  • Color fast. The fabric absorbs dye in warm water and does not bleed dye during the laundering process.

  • Doesn’t shrink. Unlike most forms of rayon, modal is much less likely to shrink in the wash.

  • Eco-friendly. Modal is made from regenerative plants and there are fewer chemicals used in the production process than with other types of rayon.

  • Biodegradable. Modal is completely biodegradable.

  • Water Efficient. Modal is generally considered a more eco-friendly alternative to cotton because beech trees don’t require much water to grow and therefore the production process uses about 10-20 times less water.


While modal fabric has many positive qualities, there are some potential drawbacks to consider:

  • Wrinkling: Modal fabric can be prone to wrinkling, especially if it is not properly cared for. To maintain its appearance, it is advisable to handle and store modal garments carefully.

  • Durability: While modal is known for its softness, it may not be as durable as some other fabrics. Prolonged and intensive use or rough handling can lead to wear and tear over time.

  • Environmental Impact: While modal is derived from natural materials, the processing of these materials into fabric involves the use of chemicals. The environmental impact can vary depending on the manufacturing practices of specific brands and production facilities.

  • Cost: Modal fabric can be more expensive than some other alternatives. While its qualities may justify the cost for some consumers, budget considerations could be a drawback for others.

  • Color Fading: Modal fabric may be more susceptible to color fading over time, especially when exposed to excessive sunlight or frequent washing.

It's important to note that the perceived drawbacks can vary depending on individual preferences and the intended use of the fabric.

blue modal fiber

More about Modal Fiber

Will Modal Fiber Shrink?

Modal fiber has a reputation for being more stable and resistant to shrinkage compared to some other fabrics. However, like any textile, modal can still experience some degree of shrinkage under certain conditions. The extent of shrinkage can depend on factors such as the specific modal blend, the manufacturing process, and how the fabric is treated during washing and drying.

To minimize the risk of shrinkage, it's advisable to follow the care instructions provided by the garment manufacturer. Generally, washing modal fabrics in cold water and avoiding high heat during drying can help maintain their size and shape. Line drying or using a low-heat setting in the dryer is recommended to reduce the likelihood of shrinkage.

Is Modal Fiber Breathable

Modal is derived from natural materials, usually beechwood pulp, and its structure allows for good air circulation. This property makes modal fabrics comfortable to wear, especially in warm or humid conditions, as it helps in regulating body temperature and preventing discomfort caused by trapped heat and moisture. The breathability of modal contributes to its popularity in the production of various clothing items, including activewear, underwear, and casual wear.

Is Modal Fabric Stretchy?

Modal is an exceptional stretch fabric, making it well-suited for athletic wear. While it may not possess the same level of stretchiness as materials like viscose or lyocell, its stretch properties contribute to its appeal in activewear.

As we conclude our exploration into the realm of modal fiber, we invite you to embrace the sheer elegance and sustainable sophistication that this remarkable textile brings to the table. From its origins in the heart of beechwood trees to its soft touch against the skin, modal has woven itself into the fabric of conscientious fashion. As you consider your wardrobe choices, let the eco-friendly allure of modal be a guiding thread, connecting you to comfort, style, and a greener tomorrow. Elevate your fashion journey with the soft embrace of modal, and embark on a conscious path where luxury meets sustainability. The story of modal continues to unfold, and we're excited to see how it will shape the future of textiles, fashion, and our collective commitment to a more sustainable world.


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Meet Valinda

Hi there, I am the founder of the green and happy mom blog and green and happy shop. After battling severe depression, I am determined to make the world a little better and I want to take you along that journey with me. 

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