Colourfastness to rubbing
This part of ISO 105 specified a method for determining the resistance of the colour of textiles of all kinds, including textile floor covering and other pile fabrics, to rubbing off and staining other materials. Specimens of the textile are rubbed with a dry rubbing cloth and with a wet rubbing cloth. The staining of the fabrics is assessed by comparison with the grey scale.

Test specimen:
2 pieces dark purple knitted fabrics
Size:
16cm X 5cm
Specimens are cut and positioned for testing with the long dimension oblique to warp and weft or wales and courses.
Two specimens are prepared one each for dry and wet rubbing.

AATCC Crockmeter
Test Cloth: 12 undyed bleached cotton lawn cut in 5cm squares
Distilled water
Grey Scale for assessing Staining
Light box (D65 daylight)

Procedures
First, dry crocking test was started. Specimen that wale through longer side was put on the crockmeter base and covered by a specimen holder.
Cotton rubbing cloth was mounted on the end of finger with a ring clip with loops upward to avoid contact between the clip and the specimen.
The finger was placed downward so the specimen was contacted with it. The meter handle was then cranked 10 turns. 1 second was used for each turn.
Ring clip was removed and the cotton rubbing cloth was taken off from the finger.
The change in whiteness of the rubbing cloth was assessed with the grey scale.
Procedures 1.2-1.5 were repeated 3 times.
Then, the specimen that wale through longer side was replaced by the one with course through longer side.
Procedures 1.2-1.5 were repeated 3 times.
Then, wet crocking test was started. 6 Cotton rubbing clothes were put into distilled water and taken out and tissue was used to adsorb excessing water.
Procedures 1.2-1.8 were repeated but dry rubbing clothes were replaced by wet rubbing clothes. And wet rubbing clothes were dried before whiteness assessing.

From the result obtained, the fabric has a good colorfastness to rubbing.
The staining problem of a wet test cloth in wale direction is slightly more serious than that of a dry test cloth. In other words, the colourfastness to dry rubbing rating is better than the colourfastness to wet rubbing. This is because when the dye used for dyeing purple coloured knitted fabric come in contact with test cloth in wet stage, the chance of colour transfer from the purple knitted fabric to the wet test cloth increases. The degree of colour transfer depends on many factors such as dye affinity of the dye molecules with the specimen and the dye concentration used for dyeing. The dye molecules have higher affinity to the wet cotton cloth so that the dye molecules migrate to the wet cotton cloth when rubbing.

The rubbing action on the fabric probably affects the rubbing effects. For instance, the pressure given on the fabric, abradant surface and time scale. A double and elongated image was obtained if the test cloths are not tightened enough by the wire clip. In addition, uneven dye pick up may be resulted. This may due to the percentage moisture on the wetted cotton cloth was not in a uniform level. It can be solved by resurfaced the crocking finger and tested it again. Furthermore, it is required to check the direction of test cloth and specimen. Otherwise, the test cloth will streak in the image.

Generally, the testing result of colourfastness to rubbing is above standard. Therefore, the colourfastness of rubbing can be considered as very good.