Colour Fastness to Light Test Methods and Acceptable Limits
Colour Fastness to Light is verified through ISO 105-B02 xenon arc. Knowing how the method works avoids rejecting fabric that actually meets the requirement.
Method overview
ISO 105-B02 xenon arc defines sample size, conditioning and calculation, so values are comparable only within the same revision. Working figures for Colour Fastness to Light normally sit around grade 4-6 by end use in mainstream production. Note ISO 105-B02 xenon arc on the tech pack so nobody tests against an older revision.
Result interpretation
Read the value together with construction notes; grade 4-6 by end use is only meaningful for similar fabrics. Record elastane content alongside Colour Fastness to Light, because blends shift the measured value. A result outside grade 4-6 by end use usually points to process drift rather than to the fibre itself.
Typical limits
Buyers commonly write grade 4-6 by end use with a stated tolerance, then verify against ISO 105-B02 xenon arc. Keeping reference values for Colour Fastness to Light lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 105-B02 xenon arc, since both affect the reading.
Sources of variation
Conditioning time, operator technique and shade all influence the result. Working figures for Colour Fastness to Light normally sit around grade 4-6 by end use in mainstream production. Note ISO 105-B02 xenon arc on the tech pack so nobody tests against an older revision.
Documentation
Record the standard revision on every report, because older versions can differ from current practice. Record elastane content alongside Colour Fastness to Light, because blends shift the measured value. A result outside grade 4-6 by end use usually points to process drift rather than to the fibre itself.
