DigiGrade > Colour Fastness
COLOUR FASTNESS
- Colour fastness is a measure of how permanent a colour is on fabric.
- Colour can be adversely affected by a number of factors including exposure to light, to water as in washing and to normal wear and tear such as rubbing against a surface.
- Various test methods have been created to assess how the colour is affected by these different parameters and a numerical value is then established to indicate the degree of colour change.
- Tests are performed with a control fabric included, which is usually white or un-dyed, the control fabric is also assessed for the staining which results from contact with the test material.
- For washing and perspiration tests the control fabric is normally a multi-fibre strip - a strip of 6 different fibre components acetate, cotton, acrylic, polyamide, polyester and wool.
- This gives the ability to assess the potential for staining on any fibres, which may be in the same wash cycle.
- The results are assessed by grading against standard A04/A05 greyscales* with a grade of 5 indicates no change in colour or staining and a grade of 1 is substantially different. .
* The grey scale consists of nine pairs of non-glossy neutral grey coloured chips, which illustrate the perceived colour differences. These give a corresponding fastness rating of 5, 4-5, 4, 3-4, 3, 2-3, 2, 1-2, and 1)