Technical Insight
Antimony-Free Laser-Marking Routes for TPU Ear Tags
Define antimony-free at the formulation and supply-chain boundary and require a controlled composition declaration for each proposed candidate. When an existing formulation uses Antimony Tin Oxide (ATO), record it only as the antimony-containing incumbent control, not as an antimony-free candidate.
Author: Aurexene Materials Engineering Team · Last updated: 2026-08-28
Quick Answer
Define antimony-free at the formulation and supply-chain boundary and require a controlled composition declaration for each proposed candidate. When the existing formulation uses Antimony Tin Oxide (ATO), record it only as the antimony-containing incumbent control, not as an antimony-free candidate.
Evidence scope: This page provides method-conditioned engineering guidance. It does not claim that one commercial grade is a drop-in replacement, universally superior, or qualified for a finished part without matched evidence.
Problem
Define antimony-free at the formulation and supply-chain boundary and require a controlled composition declaration for each proposed candidate. If the existing formulation uses ATO, record it as the antimony-containing incumbent control, not as an antimony-free candidate.
The decision boundary includes the complete host formulation, colour package, supplied additive form, compounding and moulding history, part geometry, delivered laser state and the measurement method. A result is not transferable when one of those conditions changes without review.
Mechanism
The qualification plan must identify the declared candidate composition, intended marking response, delivered laser state, and damage boundary. It must not infer antimony-free status or performance equivalence from a product name or chemistry family.
Record pulse state, focus, overlap, path, polymer, pigments, fillers, geometry, and the declared response and defect criteria for each comparison. Any mechanism or material-performance conclusion requires matched evidence for that specific system.
Tradeoff
A proposed change from an antimony-containing incumbent requires a matched comparison of the declared colour, loading, dispersion, process, mark, mechanical, durability, and documentation criteria. Chemistry alone does not establish equivalence.
Define a feasible region and margin with predeclared contrast, edge, surface-integrity, unmarked-colour, processing, mechanical, durability, and cycle criteria; do not select from a single visual coupon.
Material Strategy
Use a declared candidate list only after each proposed material has a controlled composition declaration. Where the existing formulation uses ATO, use it only as the antimony-containing incumbent control. This page does not identify an antimony-free commercial candidate or a product recommendation.
- Freeze the host grade, colour, thickness, geometry and acceptance criteria.
- Verify the controlled composition declaration and state the active-content and supplied-form comparison basis.
- Screen the declared candidates and laser variables in a bounded matrix and preserve failed runs.
- Confirm the selected window across relevant lots, parts, tools and exposures.
Recommended Architectures
| Architecture | Use when | First validation gate |
|---|---|---|
| Matched baseline | The current material, colour and laser recipe require a reproducible reference. | Antimony-free route qualification |
| Bounded screening ladder | Loading, supplied form, colour or delivered laser variables must be separated. | restricted-substance definition; candidate chemistry identity; host and colour compatibility; matched mark window; lot and change control |
| Production confirmation | A candidate window must transfer across lots, geometry, tools or lifecycle exposures. | Margin, repeatability, failures and requalification triggers |
Controls That Must Stay Visible
| Order | Control | Review rule |
|---|---|---|
| 1 | restricted-substance definition | Hold the other declared formulation, process, geometry and measurement conditions constant before attributing an effect. |
| 2 | candidate chemistry identity | Hold the other declared formulation, process, geometry and measurement conditions constant before attributing an effect. |
| 3 | host and colour compatibility | Hold the other declared formulation, process, geometry and measurement conditions constant before attributing an effect. |
| 4 | matched mark window | Hold the other declared formulation, process, geometry and measurement conditions constant before attributing an effect. |
| 5 | lot and change control | Hold the other declared formulation, process, geometry and measurement conditions constant before attributing an effect. |
Measurement & Validation
Primary response: Antimony-free route qualification.
Method: Verify a controlled composition declaration, then run matched formulation, laser, colour, mechanical, and durability tests against a documented incumbent control when one exists. If that control is ATO, label it as antimony-containing.
Report the unit or grade together with instrument or verifier geometry, specimen state, conditioning, repeats, distribution or uncertainty, failures and the acceptance limit. A scanner pass, photograph or supplier representative value is not a substitute for the declared method.
Qualification Boundary
- Record exact material and lot identities, controlled composition declarations, active-content basis, carrier, and colour package.
- Record compounding, drying, moulding, thickness, surface and geometry.
- Record source wavelength, pulse state, spot or focus, speed, hatch, passes, field and calibration.
- Measure marked and unmarked controls using the declared method; label any ATO control as antimony-containing.
- Confirm production and lifecycle variation, then define requalification triggers.
Primary Sources and Standards Boundary
Evidence boundary (checked 2026-08-26): The ECHA record identifies diantimony trioxide and its regulatory context; it cannot prove the absence of antimony from a supplied material or finished formulation. No named approval, controlled composition declaration, or matched performance evidence is recorded for this draft, so it remains noindex.
- ECHA diantimony trioxide substance information — Locator: identity and regulatory-obligation record for EC 215-175-0 / CAS 1309-64-4. It supports identity and regulatory-context review only; it does not substantiate an antimony-free claim for a candidate product or tag.
- Commission Implementing Regulation (EU) 2021/520 — Locator: Annex II, Part 1, points 1–3. It sets device requirements for its covered scope; it does not validate a polymer or additive grade.
- ICAR identification-device certification procedures — Locator: RFID-device and conventional-ear-tag certification procedure sections. It identifies device-level routes, not a composition declaration or formulation approval.
- ICAR Appendix B5: Laboratory Test for Conventional Plastic Ear Tags — Locator: material characterization, environmental exposure, abrasion, readability, and colour-contrast sections. It does not prove a candidate formulation is antimony-free or performance-equivalent.
Related Applications
Engineering Support
Need to apply this boundary to a grade, formulation, test method, or production route? Discuss it with the Aurexene Materials Engineering Team.