pH Value of Fabric How It Changes with Construction and Elastane Content
pH Value of Fabric 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 pH Value of Fabric normally sit around 4.0 to 7.5 for skin contact in mainstream production. Note ISO 3071 aqueous extract 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 3071 aqueous extract, so retest after any blending change. Record elastane content alongside pH Value of Fabric, because blends shift the measured value. A result outside 4.0 to 7.5 for skin contact 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 pH Value of Fabric lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 3071 aqueous extract, since both affect the reading.
Typical range
Working values stay around 4.0 to 7.5 for skin contact for mainstream activewear. Working figures for pH Value of Fabric normally sit around 4.0 to 7.5 for skin contact in mainstream production. Note ISO 3071 aqueous extract on the tech pack so nobody tests against an older revision.
Development advice
Change one variable at a time, then verify against ISO 3071 aqueous extract before moving to the next sample round. Record elastane content alongside pH Value of Fabric, because blends shift the measured value. A result outside 4.0 to 7.5 for skin contact usually points to process drift rather than to the fibre itself.
