Colour Fastness to Light How to Read It on a Lab Report
Laboratory reports present Colour Fastness to Light in a compact format. Knowing what each line means prevents misreading.
Definition reminder
resistance to fading under light. 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.
Common report layout
The report states method ISO 105-B02 xenon arc, sample description, conditioning, and the measured result. 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 result
Values near grade 4-6 by end use usually indicate a conforming lot, assuming the fabric matches the sample submitted. 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.
Red flags
Missing revision numbers, unusual conditioning, and results without units all signal unreliable data. 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.
Questions to ask
Ask the laboratory for the standard revision and sample description before accepting or rejecting a result. 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.
