Lining Fabric Colorfastness Standards Demystified What ISO, AATCC, and SDC Test Results Actually Tell Buyers About Long-Term Sustainable Textile Performance

When a buyer sources lining fabric wholesale, a test report showing a colorfastness grade of 4 or 4-5 looks reassuring on a spec sheet. But what does that number actually mean in practice, and does it apply to how your end customer will wash, wear, and expose that garment to light? Colorfastness test results are only as useful as your ability to read them correctly. ISO, AATCC, and SDC standards measure overlapping but distinct things, using different equipment, different grading scales, and different pass thresholds. Misreading them can lead to costly claims, consumer complaints, and sustainability missteps. This guide decodes what each standard actually tests, how to compare results across frameworks, and what a rigorous test report should look like for lining fabrics in 2026.

TL;DR

• ISO, AATCC, and SDC colorfastness standards are not interchangeable; each uses different test conditions, rating scales, and acceptable thresholds.

• Colorfastness to washing, crocking, and light are the three dimensions buyers must evaluate separately for lining fabrics.

• A grade of 4 under one standard does not automatically equal a grade of 4 under another standard for the same fabric.

• Sustainable and recycled fibers can perform differently in colorfastness tests compared to conventional materials, making fiber-specific testing essential.

• Specifying the correct AATCC test methods or ISO equivalents in your purchase order prevents disputes before they start.

About the Author:

This article is produced by Sungil Tex, a Hong Kong-based sustainable lining supplier operating since 2008, serving over 200 global apparel brands including Burberry, Ralph Lauren, and Calvin Klein across 20 countries. Sungil Tex's technical team works daily with colorfastness specifications across ISO, AATCC, and SDC frameworks for recycled and sustainable lining programs.

What Does a Colorfastness Grade Actually Measure?

Colorfastness is a fabric's resistance to color loss or transfer under specific conditions such as washing, rubbing, light exposure, or perspiration [1]. The grade is not a single universal score. It is always relative to a specific test method, a specific staining or fading condition, and a specific fiber substrate. Across all major frameworks, grades run from 1 (poor, severe change) to 5 (excellent, no detectable change), assessed using standard grey scales for color change and staining [2].

For lining fabrics, three dimensions matter most:

• Washing: Does the lining bleed onto the shell fabric or lose depth through repeated laundering?

• Crocking: Does dry or wet rubbing transfer dye to other surfaces or the wearer's skin?

• Light: Does the color fade from UV or indoor light exposure over the garment's use life?

How Do ISO 105, AATCC, and SDC Standards Differ for Washing Tests?

Building on those three dimensions, the washing test is where standards diverge most sharply, and where buyers make the most costly assumptions. ISO 105-C06 and AATCC 61 are both used to evaluate colorfastness to washing, but they are not equivalent tests and should not be substituted without adjustment [6].

Parameter	ISO 105-C06	AATCC 61
Scope	Home and commercial laundry worldwide [5]	Primarily North American home laundering [6]
Test temperatures	Multiple options (A1S through E2S), 40°C to 95°C	Multiple options (1A through 5A), 40°C to 95°C
Detergent used	ECE reference detergent (without optical brighteners in some variants)	AATCC Standard Reference Detergent WOB
Grading scale	ISO Grey Scale 1-5	AATCC Grey Scale 1-5 (equivalent concept, slight visual calibration difference)
Multifiber adjacent fabric	ISO multifiber DW	AATCC multifiber adjacent fabric

The practical implication: a lining that passes ISO 105-C06 at 40°C does not automatically pass AATCC 61 at the equivalent cycle. If your brand specifies one and the laboratory tests to the other, the result is technically non-comparable [6]. Buyers sourcing lining fabric wholesale for North American markets should specify AATCC 61; those sourcing for European or global programs should specify ISO 105-C06, with the specific sub-test clearly noted.

What Do AATCC Test Methods Cover Beyond Washing?

Beyond colorfastness to washing, AATCC test methods address crocking and light fastness, which are equally critical for linings but often under-specified [7]. AATCC 8 measures color transfer through rubbing friction, simulating abrasion between the lining and a shell fabric or skin [4]. The test evaluates both dry and wet crocking conditions separately, because wet crocking is almost always weaker and represents the condition closest to perspiration contact [4].

• AATCC 8 (crocking): Uses a crockmeter to rub white test cloth against the fabric. Grades dry and wet crocking independently on the 1-5 scale.

• ISO 105-X12: The closest ISO equivalent to AATCC 8, using similar equipment but with slight differences in applied pressure and rubbing cloth specification [4].

• AATCC 16.3 (light fastness): Exposes fabric to a xenon arc light source and compares fading against AATCC Blue Wool Standards on a 1-8 scale, where 8 is excellent [3].

• ISO 105-B02: The ISO equivalent for light fastness, also using a xenon arc but graded against ISO Blue Wool References on a 1-8 scale.

The light fastness scale deserves special attention: unlike washing and crocking (graded 1-5), light fastness is graded 1-8. A lining fabric rated 4 for light fastness is not comparable to a lining fabric rated 4 for washing. The scales are structurally different [3].

Why Do Recycled and Sustainable Fibers Behave Differently in Colorfastness Tests?

A related but distinct question concerns whether sustainable fiber choices alter colorfastness performance. The answer is yes, and it matters more than most buyers realize. Recycled polyester, dope-dyed fibers, and biodegradable viscose variants each interact with dye chemistry differently from virgin conventionally dyed fabrics.

• Dope-dyed fibers: Color is introduced into the polymer melt before extrusion rather than applied in a dye bath afterward. This typically produces superior light fastness and washing fastness because the colorant is locked inside the fiber structure rather than sitting on its surface.

• Recycled polyester (rPET): The recycling process can affect the dye uptake profile of the polymer. Testing to the same standard as virgin polyester is required; do not assume equivalent performance without a test report.

• Biodegradable viscose (Tencel, Ecovero): Cellulosic fibers generally require reactive or direct dyes. These dye classes have different washing fastness profiles from disperse dyes used on polyester, so the applicable test standard and acceptable threshold may differ by fiber type.

Sungil Tex's dope-dyed pocketing and lining materials illustrate a practical benefit here: because the color is integrated at the fiber level, these products reduce both chemical usage in production and the risk of color migration in end use, giving buyers test performance advantages alongside environmental credentials.

How Should Buyers Write Colorfastness Requirements Into Purchase Orders?

Stepping back from the technical detail, a separate concern is how buyers translate their knowledge of these standards into enforceable supplier requirements. Vague specifications like "good colorfastness" create room for dispute. A well-written colorfastness clause in a purchase order or technical specification should state:

1. The specific test method by number (e.g., ISO 105-C06 Test A1S, or AATCC 61 Test 2A), not just the standard family.

2. The minimum acceptable grade for each dimension (color change and staining) and each fiber in the multifiber adjacent fabric.

3. Whether dry crocking, wet crocking, or both are required for AATCC 8 or ISO 105-X12.

4. The light fastness method and minimum grade if the garment's outer shell fabric will have any significant light exposure in end use. Note that light fastness is generally not required for lining fabrics, as they are on the inside of the garment and not exposed to light.

5. The accredited laboratory whose results you will accept, to prevent self-testing submissions.

Typical minimum grades for apparel lining accepted by major brands run at grade 3-4 for washing and staining, and grade 3 or higher for wet crocking, though these thresholds vary by market, end use, and brand policy [1].

Frequently Asked Questions

Is ISO 105-C06 the same as AATCC 61?

Both test colorfastness to washing, but they use different detergents, different multifiber adjacent fabrics, and are calibrated for different laundry practices. Results are not directly interchangeable

[6]

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What is a passing colorfastness grade for lining fabrics?

Most major apparel brands set minimum grades of 3-4 for washing (color change and staining) and grade 3 for wet crocking. Light fastness is generally not required for lining fabrics since they are not exposed to light inside the garment. Exact thresholds should always be confirmed with the brand's technical team

[1]

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Does the AATCC 16.3 light fastness scale work the same as the washing scale?

No. Light fastness is graded 1-8 (not 1-5), where 8 represents no detectable fading. A grade of 4 for light fastness is a moderate result, not the same as a grade of 4 for washing

[3]

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Do dope-dyed linings perform better in colorfastness tests?

Generally yes. Because the colorant is embedded in the fiber rather than applied externally, dope-dyed materials typically show stronger washing and light fastness performance than conventionally dyed equivalents.

Which textile testing standards should I specify for a lining sold in both the US and EU?

Specify both AATCC test methods for North American compliance and ISO 105 equivalents for European compliance. Require test reports for each separately, as results cannot be cross-applied between the two frameworks

[5]

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Does recycled polyester lining require different colorfastness testing than virgin polyester?

The same test standards apply, but performance cannot be assumed equivalent. Recycled polyester should be tested independently under the same methods, and test reports should be reviewed alongside the fiber certification documentation.

What is the SDC (Society of Dyers and Colourists) role in colorfastness testing?

SDC provides standardized grey scales, Blue Wool reference standards, and multifiber adjacent test cloths that laboratories worldwide use to grade results under both ISO and AATCC methods. SDC standards underpin the physical measurement tools used in both frameworks, making them an enabler of consistent cross-lab comparisons.

About Sungil Tex

Sungil Tex is a Hong Kong-headquartered sustainable lining and textile supplier operating since 2008, recognized as Asia's leading global lining supplier and serving over 200 international apparel brands including Burberry, Ralph Lauren, Calvin Klein, and Tommy Hilfiger. The company maintains over 10,000 running color stock items available without minimum order quantity requirements, making it one of the most flexible suppliers in the lining fabric wholesale market. Sungil Tex's product range covers more than 50 types of recycled and sustainable textiles, including GRS-certified recycled polyester, BCI cotton, and biodegradable viscose options certified under GOTS and verified for biodegradability across multiple environments. With regional offices across 13 countries and integrated supply chain operations under the TOPLINE brand, Sungil Tex delivers competitive pricing on sustainable materials alongside rigorous quality and certification documentation for buyers who need verified performance data.

Ready to source lining fabrics with verified colorfastness performance and full sustainability certification?

The Sungil Tex technical team can help you specify the right test standards for your program, review supplier test reports, and match you with lining options that meet your performance and environmental requirements. Visit www.sungiltex.com to learn more or get in touch.

References

1. What Is Colorfastness? A Buyer's Guide To AATCC/ISO Tests 2025 (fabric-supplier.com)

2. Ultimate Guide to Color Fastness of Fabrics | EYSAN FABRICS (www.eysan.com.tw)

3. AATCC 16.3 Colorfastness to Light Test Method: A Guide | QIMA (blog.qima.com)

4. Comparing AATCC 8 and ISO 105 X12 Method Standards (www.worldoftest.com)

5. Color Fastness Standards Compared: ISO, AATCC & JIS - (chiuvention.com)

6. ISO 105-C06 vs AATCC 61: The Complete Guide to ... (darongtester.com)

7. Fabric Colorfastness Testing: 7 ISO And AATCC Standard Methods (vietextile.com)