AATCC 61 Explained: Insights from a Textile Lab Technician

Colorfastness to laundering, home, and commercial: accelerated (AATCC 61) is a test method developed by the American Association of Textile Chemists and Colorists. This colorfastness test is mainly mandatory for American retailers. Some European retailers are adding this test to their program manuals due to its importance. This article will explain the AATCC 61 test method, its importance, working procedure, and rating system.

Introduction to Colorfastness to Washing

Colorfastness is an important parameter in the textile industry used to determine how well a fabric retains its original color after exposure to washing, rubbing, light, and other environmental conditions. In modern textile manufacturing, especially for export markets, maintaining high colorfastness standards is essential for meeting buyer requirements and avoiding costly claims and rejections. Tests such as AATCC 61 are widely used to evaluate color durability under accelerated laundering conditions, helping manufacturers predict real-life performance. A strong understanding of colorfastness not only improves product reliability but also enhances brand reputation, customer satisfaction, and long-term commercial success in global markets.

Science Behind Colorfastness

The science behind colorfastness is based on the interaction between dye molecules and the fiber’s structure, as well as the bond’s resistance to external influences such as water, temperature, detergents, and mechanical action. During dyeing, dyes penetrate the fiber and, in the case of reactive dyes and cellulosic fibers (e.g., cotton), form covalent bonds, while disperse dyes are physically entrapped in polyester fibers. Poor fixation or incomplete dyeing results in loose dye molecules that can easily wash out or transfer to adjacent fabrics. In AATCC 61 testing, accelerated conditions such as high temperature, controlled detergent concentration, and mechanical agitation simulate multiple washing cycles in a short time. The extent of the color change and staining observed reflects the stability of the dye-fiber bonding, making it a reliable indicator of real-world washing performance and durability.

Importance of Colorfastness to Laundering Test

Many consumers buy black or blue denim jeans or dark-colored items. If the color fades after washing, they will claim to the retailers and the brand. This can be a serious issue for retailers and manufacturers as well.

The fastness of home-laundering textile testing standards should be met and pass the retailers’ criteria. That is why the manufacturers test their samples before dispatching them.

This test method explains the procedure for evaluating colorfastness to laundering in textiles, apparel, trims, and accessories.

This method can be equalized to approximate the color change effects of five typical home laundering.

AATCC 61 Application Areas

1. AATCC 61 applies to all types and forms of textile fibers, yarns, fabrics, clothing, trims, and accessories.
2. For white colors (may be fabric, print, trims, and accessories), multiber Fabric is not necessary to include unless requested by the client.
3. This test method does not include the evaluation of hard trims or accessories such as sequins or beads.
4. For overall foil- or glitter-printed samples that cover the fabric’s base color, testing is not necessary unless requested by the client.

AATCC 61 Apparatus and Equipment

Here is the list of Apparatus and textile testing Equipment required for AATCC 61:

1. A laundromat machine is required to rotate canisters in a thermostatically controlled water bath at 40 ± 2 rpm.
2. Stainless-steel lever-lock canisters, type 1 – 500mL.
3. Stainless steel lever-lock canisters, type 2 – 1200mL.
4. Stainless steel balls, 6 mm diameter.
5. White synthetic rubber balls 9- 10 mm diameter.
6. Electronic balance for weighing detergent.
7. Wash glass.
8. Grey scale for rating color change and color staining.
9. A color-matching cabinet for rating.

AATCC 61 Reagents and Consumables

To test AATCC 61, we need the below-listed reagents and consumables:

1. 1993 AATCC WOB standard reference detergent powder (from approved suppliers).
2. Sodium hypochlorite.
3. Multifiber fabric number 10 (heat-sealed).
4. Multifiber fabric number 1 for silk specimens.
5. Grade 3 water.
6. White-colored sewing thread.

Sample Preparation Laboratory Best Practice

A minimum of one specimen is required for the test. You can use multiple specimens for improved precision and accuracy.

Size: For the 1A test, the sample size should be 10 cm x 5 cm; for the 1B, 2A, 3A, and 5A tests, the sample size should be 5 cm x 15 cm. For multicolored garments, you need to cut enough specimens to ensure all colors in the garment are tested.

Attachment: A piece of heat-sealed multifiber fabric number 10 is attached for testing 1A/2A/3A. However, the multifiber fabric is not attached when testing 1B (Unless the client requests it, like Land Mark Group), 4A, and 5A.

The multifiber test fabric is sewn or stapled along one of the 50 mm edges of the test specimen and must be in contact with the test specimen’s face. The multifiber fabric is so attached that the fiber stripes of the multifiber test fabric are parallel to the length direction of the test specimen. It will help to stain the multifiber test fabric properly.

If you get some trims like ribbons or twill tapes that are narrower than 5 cm, put enough specimens side by side to cover 5 cm width of the multifiber test fabric.

Testing Liquor Preparation

We will prepare the below steps to make testing liquor (describing 2A program):

1. Take 1 liter of grade 3 water.
2. Take 1.5-gram WOB (without an optical brightening agent) detergent powder with the help of an electronic balance.
3. Now, mix the detergent powder with water using a glass rod, stirring.
4. You can keep the liquor in a reagent bottle to store for 3-4 hrs. However, it is recommended to test samples with freshly prepared liquor.

Testing Procedure

The testing procedure of AATCC 61 is described in the steps below:

1. At first, we will switch on the washing machine.
2. Now we will ensure that the water level is at the preset water level. As needed, we will add or remove water by adjusting the tap on the side of the water bath.
3. Then we will set the water temperature meter to the required temperature, like 49⁰ C for the 2A test.* Use Sodium Hypochlorite, but use “gram” measurement to measure the amount. The use of chlorine is limited to 4A and 5A test programs. But these programs are very limited, so we don’t get these options to test. This is just for your knowledge. The most common test numbers are 1A, 2A, and 1B. Test (refer to the Chart below)
4. Now we will turn on the heater switch.
5. We will heat the water in the drum until it reaches the desired temperature as indicated in the test program 2A (49⁰ C).
6. We will take the required volume of wash liquor.
7. Now we will choose the appropriate conditions as per Table 2A.
8. Then the containers (with 50 stainless-steel balls and 150ml liquor) are installed in the rotor and run for 2 minutes to warm the solution internally.
9. Now each container is removed and opened or opened while held in place on the shaft.
10. We will place one specimen in one container and clamp on the cover.
11. Then we will check the container’s seal by turning it upside down. If leakage is noticed, we will change the gasket.
12. We will place the containers horizontally in the adapters onto the rotor of the apparatus. We will check the containers are fastened in such a manner that the covers strike the water first when the rotor rotates and will place an equal number of specimen containers on each side of the shaft. If bubbles are observed on the container’s cover when the container strikes the water, it indicates leakage in the container, and we will replace the canister.
13. We will run the apparatus for 45 minutes.
14. After completing 45 minutes, the machine will stop, and we will immediately remove the specimen containers from the apparatus.
15. The contents are emptied into a beaker, keeping each test specimen in a separate beaker. The specimen containers are rinsed with distilled or deionized water at 40 ± 3°C (105 ± 5°F).
16. We will rinse each test specimen three times in beakers containing distilled or deionized water at 40 ± 3°C (105 ± 5°F), with occasional stirring or hand squeezing, for 1 minute.
17. We will now remove excess water from the test specimen by blotting.
18. Lastly, we will dry the specimens in an air-circulating oven, where the temperature is maintained below 71°C (160 °F), or air-dry in ambient conditions until dry.

• Conditioning The Test Specimens
  We will condition the specimens for one hour in the conditioning room (65 ± 2% RH, 21 ± 1°C (70 ± 2 °F)) by laying each specimen separately on a perforated shelf of the conditioning rack.
• Preparation for Evaluation
  The ravelled yarns are trimmed off, and any loose fiber and yarn on the surfaces of the tested specimens and staining fabric (the multifiber test fabric) are lightly brushed off. Pile fabric specimens are brushed in the required direction to restore them as nearly as possible to the same pile angle as the untested specimens.
• Evaluation
  Now it’s time to evaluate the tested specimen using a light booth for color matching. Three trained observers will rate each test specimen independently. If we get a marginal result to the requirement, we will report the average rating to the nearest half grade towards the higher rating. As we see the color staining for Nylon fiber’s First rating is Grade 3.0, the Second rating is Grade 3.5 & 3rd rater rating is Grade 3.0 and if the client requirement is Grade 3.5 then we report it as Grade 3.5.

• Color Change: The color change of the test specimen is evaluated using the AATCC Gray Scale for Color Change (AATCC EP1).Color Staining: Staining is evaluated by using the AATCC Gray Scale for Staining (AATCC EP2).
• Reporting Criteria for Fabric/Garment Lab Test Report
  1. Grade color change/color Staining: Assign a numerical grade to specimen color change and multi-fiber staining. Like Grade 4.0, Grade 2.5, etc. The grading differs from Grade 5.0 to Grade 1.0. Grade 5.0 is the best result, whereas Grade 1.0 is the worst.
  2. Intermediate grades: Use decimals (e.g., 2.5) for color changes between whole grades.
  3. Color block assessment: Evaluate cross-staining individually for each color pair. Please see the below image where we have to report separately for all the colors Light pink, Pink, Yellow & Blue.
  4. Descriptive reporting: If no grading scale rating is provided by the client, use equivalent verbal descriptions. For Example, the sample would be rated as a Grade 3.0. In this case, if the client has no grade requirement, the reported result would be a “Noticeable color change” or “Noticeable staining”.

Literature References

AATCC 61-2013e (2020)e2: Colorfastness to Laundering: Accelerated

How to improve color fastness to washing if the Sample fails

In many cases, colorfastness to washing tests can show fail results. Sometimes the sample color change fails, and sometimes the color staining on multifiber test fabric fails. So, manufacturers should adhere to the necessary guidelines to improve fastness properties.

1. It is necessary to select proper dyestuffs for the specific fiber. For cotton, need to select a reactive or vat dye. For polyester, need to select disperse dye. If the fiber is nylon, select an acid dye; for denim rope or slasher dyeing, select indigo or sulfur dye.
2. It is very important to select good dyestuff from popular brands.
3. You need to select good dyeing chemicals from popular brands.
4. You need to properly follow all the steps involved in the specific dyeing technique.
5. You need to ensure the quality of the raw grey fabric to be dyed.
6. It is necessary to maintain the overall quality control parameters in the production process.
7. It is also necessary to maintain the actual pH, time, and temperature in the dyeing process.

If the sample fails the colorfastness to washing test, you can use some techniques to make it pass.

1. Woven fabric: you can use fixers to improve fastness. The fixers will help to make a strong bond between the fiber and the dye. It is recommended to use Albafix ECO 10-20 g/l for open bath dyeing for woven fabric.
2. Knit fabric: you can try reduction cleaning, soaping, and re-washing techniques.

If it is a denim fabric, you can primarily try normal wash or enzyme wash. If fails again, you can try light bleach wash. You can also try fixing agents during the denim finishing process to improve denim’s fastness properties.

Conclusion

Colorfastness to Laundering: Accelerated is an important test both for the manufacturers and retailers. In the fast-fashion era, the entire process from manufacturing to selling is very fast. So, product quality maintenance has become a tough issue. So, this test method can play an important role in this situation.

Finally, I hope you are now clear on the colorfastness-to-washing test in the AATCC method and its importance. If you have any questions, please feel free to leave a comment in the comments section.

FAQs

What is the AATCC 61 Method?

AATCC 61 is the American colorfastness-to-washing test method developed by the American Association of Textile Chemists and Colorists. Generally, American retailers want this test to maintain the quality of their after-wash products.

What Is the AATCC Color Fastness to Washing Method?

AATCC 61 (1A, 2A, or 1B) is the AATCC color fastness to washing method.

What is AATCC 61 test method 2A?

AATCC 61 test method 2A is an AATCC washing test program. In this test program, a temperature of 490 C and a time of 45 mins are maintained. Also, a liquor volume of 150 ml is required for this test program.

What is Color Fastness Meaning?

The resistance of textile products or clothing to change its color to itself or to its adjacent materials. It happens due to exposure to environmental factors such as sunlight or rain. The products may also be encountered during processing, testing, storage, or use.

What is Color Fastness to Washing?

Colorfastness to washing is the resistance of the color of any textiles, trims, or clothing items against home laundering or washing.

What is AATCC 61 testing method?

This is a standardized textile testing method used to evaluate colorfastness to washing under accelerated conditions, simulating multiple home laundering cycles with controlled temperature, detergent concentration, liquor ratio, and mechanical agitation. This method measures both color change and color staining using a grayscale rating, ensuring compliance with the retailer’s specifications and quality standards.

What is the difference among AATCC 61 1A, 2A and 1B?

AATCC 61 includes many wash conditions, and 1A represents the mild washing with low mechanical action. 2A is the most commonly used condition, with higher temperature, steel balls, and stronger agitation. 1B uses rubber balls for the gentle action, and the selection of the testing method depends on the type of fabric, end use and buyer requirements.

How does AATCC 61 simulate washing performance?

AATCC uses a launderometer with rotating canisters containing the detergent solution, controlled temperature, and steel balls, and the combined effect of thermal energy, mechanical action, and detergent accelerates dye release, completely replicating multiple wash cycles in 45 minutes, providing a reliable prediction of real laundering performance.

What causes the poor colorfastness to washing?

Poor colorfastness results from weaker dye-fiber bonding, incorrect dye class selection or improper dye fixation. The common causes include excess unfixed dye, poor soaping process, incorrect pH, temperature or control time and low-quality dyes. These factors lead to color bleeding, fading and staining during washing cycles.

How to improve colorfastness in textiles?

We can improve colorfastness by selecting appropriate dye types, maintaining correct dyeing parameters and applying effective post-treatment processes such as soaping, reduction cleaning and fixation. The use of fixing agents and strict process control enhances the stability of the dye and wash durability.

What is color staining in AATCC 61?

Color staining refers to the transfer of dye onto adjacent fabrics during washing, and it is evaluated using the multifiber fabric and graded on a gray scale. High staining indicates poor dye fixation and can cause cross-color contamination in garments.

What is AATCC important for textile quality control?

AATCC is important for quality assurance in textile manufacturing, ensuring compliance with buyer standards, reducing the rate of rejection, and verifying wash durability. It is widely used in lab testing, product development and bulk production control for export garments.

What is gray scale rating in AATCC 61?

The gray scale rating is used to evaluate color change and staining in AATCC 61 testing and follows a 5-to-1 grading system, where grade 5 indicates no change and grade 1 indicates severe change.

What is the role of multifiber fabric in AATCC 61?

The multifiber fabric is used to assess the cross-staining during this test. It contains multiple fiber types such as cotton, polyester, nylon, acrylic, wool and acetate. This helps to determine how dye transfers onto different fibers and provides a comprehensive analysis of staining behavior and dye compatibility.

What is liquor ratio in AATCC 61 testing?

Liquor ratio refers to the proportion of test solution volume to fabric weight in the canister, and maintaining the correct liquor ratio ensures uniform chemical interaction, detergent efficiency, and reproducible results. Incorrect liquor ratio can lead to an inaccurate colorfastness evaluation and inconsistent outcomes.

Related Resources

AATCC 61/ISO 105 Automatic Textile Washing Tester SW-24AC

AATCC 61 Environmentally Friendly Color Fastness Tester to Washing DR- 24GH

AATCC 61 /ISO 105 Washing Fastness Tester SW-12AC

A Guide to Color Fastness in Textile Dyeing: What You Need to Know for Long-Lasting Vibrance