AATCC 116 Colorfastness to Crocking (Rotary)

Purpose of Test

The colorfastness to rotary vertical crocking test method is designed to determine how much color is transferred from a colored textile to other surfaces.

This test method was designed for textiles made from various fibers and with various coloring types:

Yarn
Other Fabrics
Dyed
Printed
Other Coloring Techniques

This method allows the testing of samples that are too small for the normal crocking test.

A vertical rotary crockmeter (Image Source: sdlatlas.com)

Terminology Defined

Colorfastness – Colorfastness is a fabric’s ability to retain color in various conditions.

Crocking – Crocking refers to the rubbing off of color from a fabric when subjected to abrasion.

Chromatic Transference Scale – The Chromatic Transference Scale is used to visually evaluate color transfer or staining during testing. The scale has multiple hues that allow a tester to match a hue from a color transfer test to a numerical score.

Gray Scale for Staining – The Gray Scale for Staining is used in colorfastness tests for evaluating staining on undyed textiles. The scale has shades of gray correlated with numbers that allow a tester to match shades with a numerical score.

Instrumental Assessment of Degree of Staining — An alternative to the visual method of assessing staining.

AATCC 9-Step Chromatic Transference Scale (Image Source: aatcc.org)

Test Method

Materials Used for Test

White test cloth squares

Dry
Wet with water

Testing Procedure+

Timing of Test – the colorfastness to crocking test may be performed before or after any of the following:

Washing
Drycleaning
Shrinkage
Ironing
Finishing
Any other relevant cleaning or finishing treatments

Test Procedure (Summary)

Part 1: Rub Test – The textile being tested is held against the Rotary Vertical Crockmeter and rubbed with a white crock test cloth under controlled conditions.

Part 2: Assessment & Grading – Color transferred to the white test cloth is evaluated by comparing it with one of the following options:

The Gray Scale for Staining,
The Chromatic Transference Scale, or
The Instrumental Assessment of Degree of Staining

A grade is assigned and evaluated against an acceptable quality limit.