How to Test Fabric Color Fastness Like a Pro

A Buyer’s Guide for Reliable Textile Performance

Why Color Fastness Matters

Color fastness refers to a fabric’s resistance to fading or bleeding during use and care.
In real-world applications, poor color fastness leads to:

• Customer complaints

• Brand reputation damage

• High return rates

• Failed audits

This is especially critical in:

• Medical garments (white & light colors)

• Uniforms

• Corporate wear

• Hospitality textiles

Main Types of Color Fastness Tests

1️⃣ Washing Fastness

Simulates domestic or industrial laundering.

Standards:

• ISO 105-C06

• AATCC 61

Evaluates:

• Color change

• Staining on adjacent fabrics

2️⃣ Rubbing (Crocking) Fastness

Measures color transfer due to friction.

Standards:

• ISO 105-X12

• AATCC 8

Dry rubbing ≥4
Wet rubbing ≥3 is typically acceptable.

3️⃣ Light Fastness

Resistance to fading under sunlight.

Standards:

• ISO 105-B02

• AATCC 16

Especially important for outdoor uniforms and workwear.

4️⃣ Perspiration Fastness

Assesses color stability under sweat conditions.

Critical for:

• Medical wear

• Sportswear

• Close-to-skin garments

How Tests Are Actually Conducted

Washing Fastness Example

1. Fabric + multifiber adjacent fabric sewn together

2. Washed under controlled temperature, detergent, and time

3. Dried and evaluated using grayscale

4. Rated from Grade 1 (poor) to Grade 5 (excellent)

Most commercial fabrics require:

Minimum Grade 4 for color change and staining.

Typical Buyer Requirements by Application

Why White & Light Colors Are Harder

Contrary to common belief:

• White fabrics are more sensitive to:

  • Optical brightener migration

  • Chemical residues

  • Uneven finishing

• Batch consistency becomes even more critical than for dark colors.

This aligns with the real production challenges you’ve faced in medical white garments.

Common Pitfalls in Color Fastness Control

❌ Only testing lab dips, not bulk
❌ Ignoring inter-batch differences
❌ Focusing only on washing fastness
❌ Skipping after-finishing retests

How to Reduce Color Fastness Risks

From a manufacturing perspective:

• Use reactive/disperse dyes correctly matched to fiber type

• Ensure thorough washing-off

• Apply proper fixation processes

• Control pH and water hardness

From a buyer perspective:

• Request full test reports

• Approve bulk color, not only lab dips

• Keep physical shade standards

• Verify batch consistency

Conclusion

Color fastness is not just a test result—it is the foundation of brand trust.
Professional buyers should treat color fastness testing as a core sourcing criterion, not a formality.