Colour Fastness to Washing How It Changes with Construction and Elastane Content
Colour Fastness to Washing does not stay constant when construction changes. Understanding the direction of change helps during development.
Effect of knit structure
Loop length and density move results first, usually before any yarn change is made. 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.
Effect of elastane content
More elastane raises recovery but changes the value measured by ISO 105-C06 domestic laundering, so retest after any blending change. 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.
Effect of finishing
Heat setting and softeners shift results, which explains differences between a hand sample and bulk. 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.
Typical range
Working values stay around grade 4-5 expected for mainstream activewear. 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.
Development advice
Change one variable at a time, then verify against ISO 105-C06 domestic laundering before moving to the next sample round. 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.
