Regenerated Fibers for Knitwear: Modal, Tencel, Bamboo (OEM/ODM Technical Guide)

What Are Regenerated Cellulose Fibers?

Regenerated fibers are made by converting natural cellulose (from wood pulp or bamboo) into a soluble form and then re-spinning it into yarn.
Compared with pure natural fibers, regenerated fibers offer:

• Softer and smoother hand-feel

• Higher moisture absorption

• Enhanced drape and fluidity

• Better color uptake

• Eco-friendly options (especially Lyocell)

Regenerated fibers used in knitwear include:

• Modal

• Tencel™ Lyocell

• Bamboo Viscose

• Classic Viscose/Rayon (less sustainable, but still common)

Modal for Knitwear Manufacturing

Fiber Characteristics

Modal is produced from beechwood pulp and is known for:

• Exceptional softness

• Smooth surface

• High moisture absorption

• Stronger fiber strength than viscose

• Beautiful drape

• High color brilliance

Modal is more dimensionally stable than viscose, making it better suited for fine-gauge knitwear.

Factory Behavior

During knitting, Modal behaves smoothly but requires controlled tension to prevent over-stretching.

Factory adjustments include:

• Lower knitting speed for 14–18GG

• Medium yarn twist to prevent pilling

• Controlled humidity to reduce yarn breakage

• Balanced take-down tension

Modal panels tend to grow after knitting, so steaming and finishing are essential to restore dimensional stability.

Best Applications

Modal is commonly used for:

• Women’s fine-gauge sweaters (12–18GG)

• Drape-heavy fashion tops

• Loungewear

• Soft cardigans

• Modal/cotton blends for spring/summer

Tencel™ Lyocell for Knitwear Manufacturing

Why Tencel Is Superior

Tencel™ Lyocell is considered the most sustainable regenerated fiber due to its:

• Closed-loop production (99% chemical recovery)

• Reduced water usage

• Biodegradability

• Naturally antibacterial properties

• Higher fiber strength

• Smooth, silky hand-feel

Tencel is often chosen by premium brands and sustainability-focused labels.

Factory Behavior

Tencel is strong, but its smoothness makes it slippery on knitting machines.

Factory requirements:

• Adjust yarn feeders to avoid slipping

• Use high-twist yarn for stability

• Avoid high tension to prevent sheen irregularity

• Gentle washing with minimal agitation

Tencel has better dimensional stability than viscose but still requires strict finishing to avoid shrinkage.

Best Applications

• Premium eco-friendly sweaters

• Women’s luxury tops

• Soft-touch fine-gauge knits

• Drape-forward designs

• Blended yarns (Tencel/cotton, Tencel/nylon)

Bamboo Viscose for Knitwear

Characteristics

Bamboo fibers are regenerated in a viscose-like process. They offer:

• Very soft hand-feel

• Good moisture management

• Excellent breathability

• Affordable price

• Smooth stitch appearance

However, bamboo viscose is not always inherently sustainable unless certified (e.g., Oeko-Tex, FSC).

Factory Behavior

Bamboo viscose tends to shrink more than Modal or Tencel.

Factory controls:

• Pre-shrink testing

• Soft washing

• Gentle finishing

• Avoiding high tumble drying

Bamboo viscose works well in 12–16GG fine-gauge knitwear but requires extra stability in washing.

Best Applications

• Soft-touch sweaters

• Under-layers and baselayers

• Loungewear

• Bamboo/nylon blends for durability

Classic Viscose (Rayon) for Knitwear

Classic viscose has been used for decades and remains widespread, though it is less sustainable.

Pros

• High color brilliance

• Smooth, soft texture

• Beautiful drape

• Affordable compared to Tencel

Cons

• Higher shrinkage risk

• Lower fiber strength

• Prone to growth after wearing

Often used in viscose/nylon blends for women’s fashion sweaters.

Stitch & Gauge Behavior of Regenerated Fibers

Fine-Gauge Performance (12GG–18GG)

Regenerated fibers excel in fine gauge, especially for:

• Soft women’s tops

• Drape-heavy rib knits

• Lightweight sweaters

• Clean jersey fabrics

They produce clean stitch definition but require careful tension management.

Mid-Gauge Performance (7GG–10GG)

Possible but less common, as fibers are too drapey to hold structure well.

Chunky Gauge (3GG–5GG)

Typically not recommended unless blended with nylon or cotton.

Common Production Challenges & Factory Solutions

Pilling

Regenerated fibers pill if fiber length is short or twist is low.
Solutions:

• Increase yarn twist

• Add nylon for reinforcement

• Conduct ISO 12945 pilling tests

• Apply anti-pilling finishing

Shrinkage

Viscose, Modal, and Bamboo can shrink heavily after washing.
Solutions:

• Pre-shrinking

• Controlled wash temperatures

• Relaxed drying

• Steam blocking

Growth (Fabric Stretch-Out)

Regenerated fibers tend to elongate during wearing.
Solutions:

• Add nylon or polyester support

• Strengthen rib collars and hems

• Higher GSM knitting structures

Sheen Irregularity

Tencel and viscose can show shiny patches if tension is uneven.
Solution:

• Carefully calibrated tension + feeder settings

Yarn Blends That Improve Performance

Viscose/Nylon

The most common blend for women’s fashion knitwear.

• Smooth surface

• High strength

• Stable panels

• Ideal for 12–16GG

Modal/Cotton

Great for summer and transitional collections.

• Breathable

• Soft

• Lower shrinkage

Tencel/Nylon

Premium sustainable blend.

• Cooler hand-feel

• Stronger than pure Tencel

• Excellent drape

Bamboo/Polyester

Used for affordable eco-collections.

• Stable

• Durable

• Soft

Applications for Regenerated Fiber Knitwear

Women’s Fine-Gauge Collections

Regenerated fibers are most popular in women’s premium knit programs.

Luxury & Premium Brands

Tencel and Modal are key materials for high-end drapey sweaters.

Eco-Focused Brands

Tencel is the benchmark for sustainable plant-derived knitwear.

Loungewear and Soft Basics

Modal and bamboo viscose provide unmatched comfort.

Spring/Summer Collections

Lightweight, breathable, and ideal for transitional fashion.

OEM/ODM Workflow for Regenerated Fiber Knitwear

Yarn Sourcing

Factory verifies:

• FSC certification

• Oeko-Tex Standard 100

• Lenzing Tencel certification (if applicable)

Sampling Stage

Steps include:

• Shrinkage testing

• Drape evaluation

• Stitch appearance testing

• Pilling assessment

• Adjusting tension per gauge

Sampling time: 3–5 days (more for complex draped designs).

Bulk Production Requirements

• Tension stabilization

• Avoid high-speed knitting

• Monitor needle wear

• Maintain humidity (50–65%)

Finishing & QC

Includes:

• Gentle washing

• Soft block steam

• Final measurement verification

• Colorfastness tests (ISO 105)

• Pilling grade ≥ 3 required