Different Color Fastness Tests

Color Fastness:

Color fastness is one of the important factors in case of buyers demand. The outstandingly important property of a dyed material is the fastness of the shade of color. Color fastness refers to the resistance of color to fade or bleed of a dyed or printed textile materials to various types of influences e.g. water, light, rubbing, washing, perspiration etc. to which they are normally exposed in textile manufacturing and in daily use. We have written a lot of articles on color fastness. 

Standards of Color Fastness: 

1. AATCC (American Association of Textile Chemists and Colorists) technical manual:

Describes 66 numbers of different color fastness tests.

 

2. SDC (Society of Dyers and Colorists):

In 1927, SDC (Europe) made fastness test committee.

 

3. ISO(International Organization for Standardization):

In 1947, ISO made color sub committee. ISO also grades the fastness:

For light fastness: 1~8

For other fastness: 1~5 

Factors Affecting the Color Fastness Properties: 

The chemical nature of the fiber. For example, cellulosic fibers dyed with reactive or vat dyes will show good fastness properties. Protein fibers dyed with acid mordant and reactive dyes will achieve good fastness properties and so on. That is to say compatibility of dye with the fiber is very important.

1. The molecular structure (e.g.) of a dye molecule: If the dye molecule is larger in size, it will be tightly entrapped inside the inter-polymer chain space of a fiber. Thus the fastness will be better.
2. The manner in which the dye is bonded to the fiber or the physical form present.
3. The amount of dye present in the fiber i.e. depth of shade. A deep shade will be less fast than a pale or light shade.
4. The presence of other chemicals in the material.
5. The actual conditions prevailing during exposure.