The Exchange Test Method

A-2: Colorfastness to Crocking (Rubbing)

Issue Date: 30 Apr 1993

Revision Date: 09/30/2011

1. PURPOSE AND SCOPE:

   To determine the degree of color transfer from a test specimen to other surfaces by both wet and dry rubbing. Customer dissatisfaction because of poor colorfastness is one of the main causes of return of softline merchandise. As washing, dry cleaning, ironing, etc., may affect the degree of color transfer from a material, the test may be done before, after, or before and after any such treatment.

2. PRINCIPLE:

   Test specimen is fastened to crockmeter base and rubbed with white test cloth under controlled conditions. This rubbing motion simulates the action of the human finger and forearm. Assessment of color transfer is done using AATCC Chromatic Transference Scale and a rating is assigned.

3. REFERENCE:

   AATCC Test Method 8-2007, Colorfastness to Crocking: AATCC Crockmeter Method.

4. APPARATUS AND MATERIALS:

   • 4.1 AATCC Crockmeter - See 8.1
   • 4.2 Test Cloth, cut in 5 cm (2 in.) squares - See 8.2
   • 4.3 AATCC Crockmeter Transference Scale - See 8.3
     

5. PROCEDURE:

   • 5.1 Dry Crocking Test
     • 5.1.1. Place the specimen on base of crockmeter with its long dimension in the direction of rubbing.
     • 5.1.2. Mount a square of white test cloth over end of finger on sliding arm and secure it with spiral wire clip. Position the clip with loops upwards. If the loops point downward, they can drag against the specimen.
     • 5.1.3. Lower finger on specimen and rub by making 10 complete turns of the crank - one turn per second.
     • 5.1.4 Remove test cloth and evaluate as explained in Step 6.
   • 5.2 . Wet Crocking Test
     • 5.2.1. Thoroughly wet test cloth squares in distilled water.
     • 5.2.2. Squeeze one test cloth square at a time between blotting papers under 454 grams (l lb.) for one second.
     • 5.2.3 Using the wet test cloth squares, follow steps 5.1.1. through 5.1.4.
       

6. EVALUATION:

   Evaluate the degree of color transfer from specimen to test square using Chromatic Transference Scale. Back the test square with three layers of white test cloth while evaluating color transfer.
   
   Using Chromatic Transference Scale, rate the color transfer as follows:

   Grade	Transference Scale
   5	Negligible or no color transfer
   4	Color transfer equivalent to Row 4
   3	Color transfer equivalent to Row 3
   2	Color transfer equivalent to Row 2
   1	Color transfer equivalent to Row 1

7. REPORT:

   Report color transfer by indicating numerical ratings for dry and wet crocking.

8. NOTES:

   • 8.1 AATCC Crockmeter is available from Atlas Electric Devices Co., 4114 N. Ravenswood Avenue., Chicago, IL 60613; tel: 772-327-4520; fax: 773-327-5787.
   • 8.2 Crockmeter test cloth, style #3 can be obtained from Testfabrics, Inc., P.O. Box 26, 415 Delaware St., W. Pittston, PA 19643, tel: 717-603-0432, fax: 717-603-0433; Atlas Electric Devices Co., 4114 N. Ravenswood Ave., Chicago, IL 60613, tel: 773-327-4520; fax 773-327-5787; and Textile Innovators Corp., P.O. Box 8, Windsor, NC 27983; tel: 252-794-9703, fax: 252-794-9704.
   • 8.3 The Chromatic Transference Scale, Gray Scales for Staining and White AATCC Textile Blotting Paper are available from AATCC, P. O. Box 12215, Research Triangle Park, NC 27709, tel: 919-549-8141; fax: 919-549-8933; e-mail: orders@aatcc.org.
   • 8.4 The abrasive material supplied with the Crockmeter is "Wet or Dry TriMite, Waterproof Silicone Carbide, W-320-A Soft Back" by 3M Co. available from Atlas Electric Devices Co., 4114 Ravenswood Ave, Chicago, IL 60613, tel: 773-327-4520; fax: 773-327-5787.