Colour Fastness to Washing Frequently Asked Questions
Short answers to the questions buyers ask most often about Colour Fastness to Washing.
What does it mean?
resistance to colour change and staining. Working figures for Colour Fastness to Washing normally sit around grade 4-5 expected in mainstream production. Note ISO 105-C06 domestic laundering on the tech pack so nobody tests against an older revision.
What value should be specified?
Start from grade 4-5 expected and adjust for the end use of the garment. Record elastane content alongside Colour Fastness to Washing, because blends shift the measured value. A result outside grade 4-5 expected usually points to process drift rather than to the fibre itself.
How is it tested?
ISO 105-C06 domestic laundering. Keeping reference values for Colour Fastness to Washing lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 105-C06 domestic laundering, since both affect the reading.
Why does it change between lots?
Process variables such as finishing temperature and elastane batch cause the normal spread of results. Working figures for Colour Fastness to Washing normally sit around grade 4-5 expected in mainstream production. Note ISO 105-C06 domestic laundering on the tech pack so nobody tests against an older revision.
Can results be compared across suppliers?
Only when the same standard revision and conditioning are used; otherwise measurements are not equivalent. Record elastane content alongside Colour Fastness to Washing, because blends shift the measured value. A result outside grade 4-5 expected usually points to process drift rather than to the fibre itself.
