Fibre content is not a marketing adjective. In the US and the EU it is a labelling duty with names, order and tolerances. Origin rules sit beside it. A trim mill can weave the tape; it cannot invent the percentage. That number comes from a test on the bulk, not from the fabric vendor’s WeChat.
This note is buyer education, not legal advice. Confirm the current statute with counsel for the destination market.
United States (FTC), high level
The Textile Fiber Products Identification Act and FTC rules want generic fibre names in English, by weight, on a permanent label. Care is a separate FTC rule. A commonly cited fibre tolerance is ±3 percentage points (excluding moisture), with extra rules for trims, ornamentation and exclusive fibre names. “Made in …” origin is required for covered textiles. This is a map for buyers, not a substitute for counsel or the latest FTC circular.
European Union, high level
(EU) No 1007/2011 governs textile fibre names and labelling. Fibre must appear in the language of the member state of sale. There is a minimum threshold before a fibre is named, and processing tolerances for multi-fibre cloth (trade summaries often cite a 3% processing allowance and a 5% naming threshold — confirm on the text and the lab). Origin is not an EU-wide clothing duty in the same way as the US “Made in” line, though customs and some national practices still want it, and imported goods into China must show origin plus a local responsible party.
China, because many programmes sew there
GB/T 29862 fibre-content labelling (trade summaries: 5% on each named fibre in blends, 10% on fillings) and GB 5296.4 use-instruction rules: fibre, care and size on a durable label, simplified Chinese, infant goods marked as infant goods, GB 18401 safety class (A/B/C) consistent with the hangtag.
TrimGem University puts fibre lines on the same identity pack as ISO 3758 care symbols — woven tapes, printed satins, heat-seal films — because a one-stop Guangzhou accessories desk samples the durable label, not only the brand damask. The catalogue will keep adding constructions; the test still owns the percentage.
How shipments actually fail
Inspection stories are boring and expensive: labelled 55 cotton / 45 polyester, tested as viscose; fibre name that does not match the yarn; care-tape fibre that does not match the contract. Causes: copying the fabric mill’s claim, skipping a bulk test, or (worse) substituting a cheaper fibre.
QR and RFID can carry a digital product passport later. They do not replace the on-garment fibre line today.
Practical sequence
Test bulk. Lock the artwork to the test. Sew a durable tape. Keep hangtag and tape in agreement. When the fabric lot changes, retest — do not recycle last season’s 48% cotton.
Ornamentation and exclusive fibre trademarks have extra FTC and EU naming rules; do not put a house fibre name on a tape unless the brand owns that name. Elastane at low percentages still has to be named once it crosses the local threshold.
TrimGem will weave or print what the test says. We will not write a fake legal quotation or a decorative “100% cotton” on a poly satin tape.