Dyeing and Printing Color Fastness Testing: Standards, Methods, and Applications

Dyeing and printing color fastness testing evaluates the resistance of textile colors to fading, bleeding, and staining during washing, rubbing, light exposure, perspiration, and other service conditions. As a core element of textile quality control, these tests are governed by internationally recognized standards such as the ISO 105 series, the corresponding GB/T standards, EN ISO, and JIS L methods. This technical guide explains the testing principle, sample types, test items, standard procedures, and practical applications of color fastness testing for manufacturers, brands, and accredited third-party laboratories.

Technical Overview

Color fastness is the resistance of the color of a dyed or printed textile to various treatments and environmental conditions encountered during processing, laundering, and end use. Because dyes and pigments are retained by fibers through different mechanisms, such as covalent bonding for reactive dyes, ionic attraction for acid dyes, and mechanical entrapment for pigment prints and disperse dyes, every coloration system exhibits characteristic fastness behavior that must be verified before commercial release.

Color fastness testing accelerates real-world degradation mechanisms under controlled laboratory conditions. Test specimens are subjected to washing, rubbing, perspiration, light, heat, and chemical exposures, and the results are assessed either visually against standard grey scales or instrumentally using a spectrophotometer. Color change and staining are graded from 5 (no visible change or no staining) to 1 (severe change or heavy staining), while light fastness is graded from 1 to 8 against blue wool references. These semi-quantitative grades allow objective comparison between dye lots, processes, and suppliers.

• Grey scale for assessing color change: ISO 105-A02, grades 1 to 5
• Grey scale for assessing staining: ISO 105-A03, grades 1 to 5
• Blue wool light fastness references: ISO 105-B08, grades 1 to 8
• Instrumental assessment of color change and staining: ISO 105-A05 and ISO 105-A04

The international standards framework is anchored by the ISO 105 series, which is adopted in Europe as EN ISO 105 and mirrored in China by the GB/T national standards. Japan maintains the corresponding JIS L 08xx series, and American practice is based on AATCC and ASTM procedures. Standardized auxiliary materials, including multifiber adjacent fabric, ECE reference detergent, and calibrated blue wool references, ensure reproducibility between laboratories operating under ISO/IEC 17025 accreditation.

Testing Samples

Dyed Woven and Knitted Fabrics

This is the largest sample category and includes reactive-dyed and sulfur-dyed cotton, indigo-dyed denim, disperse-dyed polyester, and acid-dyed nylon and wool. Deep and dark shades deserve particular attention because surface unfixed dye increases the risk of staining and crocking failures.

Printed Fabrics

Printed samples include pigment prints, in which color is held by an binder film on the fabric surface, as well as reactive, discharge, digital inkjet, and burn-out prints. Print systems generally show lower wet fastness than exhaust dyeing, so rubbing and washing tests are prioritized for these articles.

Garments and Components

Finished garments, sewing threads, woven labels, zipper tapes, piping, embroidery, and appliques are tested to confirm that adjacent components do not cross-stain during laundering. Testing components individually is essential when they will be assembled into multicolor products.

Yarns and Loose Fibers

Colored yarns are wound onto boards or knitted into swatches to provide a uniform test surface, while loose dyed fiber is combed into a pad before specimen preparation.

Home and Technical Textiles

Bedding, towels, upholstery fabrics, swimwear, and outdoor textiles are tested with emphasis on the fastness properties most relevant to their use, such as chlorine fastness for swimwear and high-grade light fastness for outdoor articles.

Specimens are conditioned in the standard atmosphere specified in ISO 139, typically 20 ± 2 °C and 65 ± 4 % relative humidity, before testing. Typical specimen dimensions include 100 mm × 40 mm composite specimens for washing and perspiration tests and pieces of at least 50 mm × 140 mm for crocking tests. Sampling should represent every dye lot, shade depth, and print base used in production.

Testing Items

Accredited third-party laboratories routinely perform the following color fastness tests on dyed and printed textiles:

• Color fastness to washing: ISO 105-C06, GB/T 3921, JIS L 0844
• Color fastness to rubbing, dry and wet: ISO 105-X12, GB/T 3920, JIS L 0849
• Color fastness to perspiration, acid and alkaline: ISO 105-E04, GB/T 3922, JIS L 0848
• Color fastness to water: ISO 105-E01, GB/T 5713
• Color fastness to seawater: ISO 105-E02, GB/T 5714
• Color fastness to chlorinated pool water: ISO 105-E03, GB/T 8433
• Color fastness to light, xenon arc: ISO 105-B02, GB/T 8427
• Color fastness to sublimation, dry heat: ISO 105-P01, GB/T 5718
• Color fastness to hot pressing, dry, damp, and wet: ISO 105-X11, GB/T 6152
• Color fastness to dry cleaning: ISO 105-D01, GB/T 5711
• Color fastness to saliva: GB/T 18886, required for infant textile products
• Color fastness to ozone, hypochlorite, and acid or alkaline spotting: ISO 105-G03, ISO 105-N01, ISO 105-E05 and ISO 105-E06

Testing Methods

Color Fastness to Washing (ISO 105-C06)

A composite specimen is prepared by sewing the dyed or printed fabric face-to-face with a multifiber adjacent fabric, typically type DW containing wool, acrylic, polyester, polyamide, cotton, and cellulose acetate strips. The composite is washed in sealed stainless-steel containers in a rotating wash wheel using ECE reference detergent with optional steel balls to simulate mechanical action. Common severity levels range from 40 °C for 30 minutes to 60 °C or higher for robust articles. After rinsing and drying, color change and staining of each fiber strip are graded with grey scales; commercial protocols commonly require staining of grade 3 to 4 or above.

Color Fastness to Rubbing (ISO 105-X12)

A crockmeter rubs a standard white cotton cloth, dry or wetted to 100 ± 5 % pick-up, against the conditioned specimen using a 16 mm finger under 9 N force for ten to-and-fro strokes over a 104 mm path. Staining of the rubbing cloth is assessed with the grey scale for staining. Dry rubbing commonly requires grade 4 or above, while wet rubbing for deep shades such as indigo denim is frequently accepted at grade 2 to 3 with appropriate labeling.

Color Fastness to Perspiration (ISO 105-E04)

Composite specimens are soaked separately in acidic (pH 5.5) and alkaline (pH 8.0) artificial perspiration solutions based on L-histidine monohydrochloride, placed between plates under a pressure of 12.5 kPa in a perspirometer, and kept at 37 ± 2 °C for four hours. After drying, color change and staining are graded. This test is critical for sportswear, underwear, and linings.

Color Fastness to Light (ISO 105-B02)

Specimens are exposed in a xenon-arc weathering apparatus fitted with daylight filters alongside a set of blue wool references rated 1 to 8. Exposure continues until a defined contrast is reached, and the fastness grade is assigned by comparing the fade of the specimen with that of the references. Everyday apparel typically requires grade 4 or higher, while automotive and outdoor textiles may require grade 6 or above. The American AATCC 16 procedure provides a parallel xenon-arc method.

Color Fastness to Sublimation and Hot Pressing

Sublimation fastness (ISO 105-P01) presses the specimen in contact with an undyed fabric, commonly at 180 °C for 30 seconds, to evaluate thermomigration of disperse dyes in polyester and its blends. Hot pressing fastness (ISO 105-X11) evaluates color change and staining after dry, damp, or wet ironing at 110 °C, 150 °C, or 200 °C for 15 seconds.

Color Fastness to Water, Seawater, and Chlorinated Water

Specimens are immersed in distilled water (ISO 105-E01), a 30 g/L sodium chloride solution simulating seawater (ISO 105-E02), or a chlorinated solution containing available chlorine at pH 8 (ISO 105-E03), then held under 12.5 kPa at 37 °C for four hours. These tests are essential for linings, towels, and swimwear.

Color Fastness to Dry Cleaning (ISO 105-D01)

The specimen is treated in tetrachloroethylene with steel chips in a rotating device for 30 minutes at 30 °C to simulate commercial dry cleaning, after which color change, staining of the solvent, and staining of an adjacent fabric are assessed.

Evaluation and Reporting

All visual assessments use calibrated grey scales with half-grade steps and standardized illumination, while instrumental rating converts spectrophotometer color-difference data into fastness grades according to ISO 105-A05 for color change and ISO 105-A04 for staining. Test reports identify the method, severity conditions, and the grade for each assessed parameter, providing traceable evidence for quality and compliance decisions.

Applications

Color fastness testing supports the textile industry at every stage of the product life cycle:

• Production quality control: approval of dye lots, optimization of washing-off and fixing processes, and verification of soaping efficiency after dyeing and printing
• Regulatory compliance: demonstration of conformity with national safety codes such as GB 18401 in China, which sets minimum fastness requirements for water, perspiration, and dry rubbing, including saliva fastness for Class A infant products
• Export and buyer protocols: verification against the fastness specifications commonly required for European, American, and Japanese retail markets
• Product development: comparison of dye classes, printing binders, and aftertreatment auxiliaries during formulation work
• Failure analysis: diagnosis of color loss, cross-staining, and crocking complaints, including root-cause studies on unfixed dye or thermomigration
• Care labeling: technical substantiation of recommended laundering and ironing instructions

FAQ

What is color fastness and how is it expressed?

Color fastness is the ability of a textile coloration to resist fading or bleeding. It is expressed as a grade: grey scale grades from 5 to 1 for color change and staining in most tests, and blue wool grades from 1 to 8 for light fastness, where higher numbers indicate better performance.

Which fastness grades are generally acceptable?

Typical commercial requirements are grade 4 or above for dry rubbing, grade 3 to 4 or above for washing and perspiration staining, and light fastness grade 4 for general apparel. Dark shades on cotton are often accepted at wet rubbing grade 2 to 3, provided the specification and labeling reflect it.

Why do deep shades frequently fail wet rubbing tests?

Dark shades require high dye concentrations that can exceed the fixation capacity of the fiber, leaving surface unfixed dye that transfers to the wet rubbing cloth. Thorough soaping, optimized fixing agents, and appropriate finishing can raise wet crocking performance by half a grade or more.

What is multifiber adjacent fabric and why is it used?

It is a striped reference fabric containing six fiber components, such as wool, acrylic, polyester, polyamide, cotton, and cellulose acetate. Sewn against the specimen during washing and perspiration tests, it reveals which fibers in a garment assembly would be stained by the tested coloration, making it more informative than a single-fiber adjacent.

How long does a light fastness test take?

Exposure duration depends on the target grade and instrument conditions, because testing ends when the specimen shows a defined contrast. A grade 4 result under xenon-arc exposure typically requires on the order of 40 to 80 hours of continuous irradiation, so light fastness tests are scheduled with longer lead times than wet tests.

Can a failed fastness result be corrected?

In production, yes, if the cause is unfixed surface dye, which can be reduced by improved washing-off and fixing treatments. However, limitations inherent to the dye class, such as the moderate sublimation fastness of some disperse dyes, can only be resolved by reformulating the coloration system.