How To Conduct Colorfastness to Laundering Testing
AATCC 61 is a collection of colorfastness to laundering (accelerated) tests developed in 1950. There are five different tests used to evaluate colorfastness to laundering for items with frequent washing. The tests replicate either hand washings or home launderings, with or without chlorine. Temperature, detergent, steel or rubber balls, and sometimes bleach are variables that affect the color change.
What is the Process for AATCC 61?
Test specimens are attached to multi-fiber swatches and stainless steel balls are loaded into stainless steel canisters with a certain percentage of detergent, prescribed water temperature, steel or rubber balls as an abradant, and possibly bleach. (Detergent should not contain any whiteners.)
The canisters are then loaded into a launderometer machine and the 45-minute test begins.
After laundering, specimens are dried, conditioned, and evaluated by two people using the Gray Scale for Color Change and the Gray Scale for Staining.
Fabrics included in the multi-fiber swatches are: acetate, cotton, nylon, polyester, acrylic and wool. The test results reports each rating for each individual fabric strip. From these rating a overall rating is resulted by using an average.
- How are the 1A and 1B Wash Test in the AATCC 61 Standard Conducted?
The 1A Wash Test consists of five low temperature hand launderings at 40C/105F degrees with no bleach.
The 1B Wash Test consists of five cool temperature hand launderings at 27C / 80F degrees with no bleach. For 1B only, liquid detergent and rubber balls are used. The test is conducted for only 20 minutes
- How is the 2A Wash Test in the AATCC 61 Standard Conducted?
The 2A Wash consists for five 5 low temperature home machine launderings at 38C / 100F degrees with no bleach. Most apparel is run to a 2A wash fastness used to evaluate colorfastness in an accelerated manner to replicate five home laundering procedures at a medium or warm setting (100F° +/- 5°F). These are the most common recommended washing instructions for nylon and polyester apparel.
- How is the 3A Wash Test in the AATCC 61 Standard Conducted?
The 3A Wash Test consists of five vigorous home machine launderings at 60C / 140F degrees with no bleach. Less water is used for 3A, creating more abrasion during the wash.The 3A Wash test uses very hot water with less water overall to simulate a more abrasive environment.
- How is the 4A Wash Test in the AATCC 61 Standard Conducted?
The 4A Wash test consists of five home launderings with chlorine at 63C / 145F degrees with weak bleach. Less water is used during 4A, creating more abrasion during the wash.
- How is the 5A Wash Test in the AATCC 61 Standard Conducted?
The 5A Wash Test consists of five home machine launderings with chlorine at 49C / 120F degrees with strong bleach.
How to Evaluate Color Change and Staining
There are two evaluations used with the AATCC 61 test methods: color change for dyed fabrics and staining for undyed fabrics. Two people typically evaluate the results because color change can be very subjective. A rating of 5 means there is virtually no change and excellent colorfastness. A rating of 1 means extreme change and poor colorfastness.
The Gray Scale for Staining is used in colorfastness tests for evaluating staining on undyed textiles. The scale consists of pairs of white and gray color chips that represent a difference in color or contrast (shade and strength) corresponding to a numerical grade for staining.
The Gray Scale for Color Change scale is used in visual evaluation of the changes in color of textiles resulting from colorfastness tests. Colorfastness grade 5 is represented on the scale by two reference chips mounted side by side in a neutral gray color.