Viscose and modal are both regenerated cellulose fibers. They start as cellulose, usually from wood pulp, which is dissolved and then regenerated as a fiber. They are chemically similar to cotton (both are cellulose) but are manufactured fibers, so their properties depend on how they are made.
How they differ#
Modal is a type of viscose fiber made with process conditions that give a higher degree of polymerisation and a more oriented structure. The main practical result is higher strength, especially when wet, and better dimensional stability.
| Property | Viscose | Modal |
|---|---|---|
| Dry strength | Moderate | Higher |
| Wet strength | Low: loses a large share of its strength when wet | Better retained when wet |
| Shrinkage in washing | Can be high | Lower, more stable |
| Hand feel | Soft, fluid drape | Very soft, smooth, slightly more body |
| Luster | Can be bright or dull | Usually soft sheen |
| Moisture absorption | High | High |
| Pilling | Depends on yarn and fabric; can be moderate | Often good, but depends on fabric |
| Typical price | Lower | Higher |
Exact values depend on the producer and fiber type, so use supplier data sheets for specifications.
Why wet strength matters#
Garments are weakest when wet. Low wet strength in viscose means that washing, wet processing and garment washing can damage the fabric more easily, and that seams can fail or fabric can distort. Modal's better wet strength makes it more suitable for garments that are washed often, such as underwear, nightwear and T-shirts.
Shrinkage and care#
Viscose fabrics often shrink and distort in washing unless well finished, and many carry "gentle wash" or "dry flat" care instructions. Modal generally keeps its shape better. Both should be tested for shrinkage on the finished fabric. See fabric shrinkage.
Typical uses#
- Viscose: dresses, blouses, lining, flowing tops, printed wovens and knits.
- Modal: underwear, loungewear, T-shirts, blends with cotton for softness.
- Both: often blended with cotton, polyester or elastane.
Labelling#
Fiber names on labels are regulated in many markets. "Modal" is a recognised generic name in several labelling systems, and brand names (such as trademarked modal fibers) can only be used with the fiber producer's permission. Confirm the correct name for the destination market's labelling rules.
Specifying#
- Fiber type and producer, with any sustainability certification claimed
- Blend percentage
- GSM, width and construction
- Shrinkage limits after the buyer's wash test
- Pilling and color fastness requirements
- Care instructions tested on the finished garment
Compare with modal vs cotton.
Production tips for both fibers#
- Cutting: fluid viscose and modal fabrics slide during spreading. Use lower lay heights, paper under-lays where needed, and sharp blades.
- Sewing: use fine needles and suitable threads, and control presser foot pressure to avoid seam waviness and puckering.
- Pressing: excessive heat and pressure can leave shine marks on dark shades. Test pressing settings on offcuts.
- Wet processing: garment washing viscose needs gentle conditions because of its low wet strength.
Worked shrinkage example#
A viscose jersey is tested: marks 50.0 cm apart in length measure 46.5 cm after washing. A modal jersey of similar construction measures 48.4 cm.
- Viscose: (46.5 - 50.0) / 50.0 × 100 = -7.0%
- Modal: (48.4 - 50.0) / 50.0 × 100 = -3.2%
These figures are an illustration of how to compare results, not typical values for either fiber. Always test your own bulk fabric with the buyer's method. The shrinkage calculator shows the working.
Related guides#
- Single jersey fabric: viscose and modal jersey compared with cotton jersey.
- Pilling test: testing the surface of soft regenerated fiber fabrics.
- Different types of fabric for dresses and clothing: where viscose and modal fit among dress and clothing fabrics.
- Top textile companies in the world: the fiber producers behind regenerated cellulose fibers.
Frequently asked questions#
Is rayon the same as viscose? "Rayon" is used in some markets as the generic name for regenerated cellulose fibers, including viscose. Labelling rules differ by country.
Why do viscose garments sometimes shrink a lot in the first wash? The fibers swell and the fabric relaxes when wet, and low wet strength makes the fabric easier to distort.