Last updated: 2026-09-02 · 5 min read

What Does Compliance Mean for Your Mold Steel and Materials?

(Restriction of Hazardous Substances) restricts six substances in electrical and electronic equipment — lead, mercury, cadmium, hexavalent chromium, and two flame retardants — and compliance for mold materials means verifying that the steel, coatings, lubricants and process chemicals do not introduce these restricted substances into the molded part. The mold maker’s obligation is material traceability: knowing what is in the steel, what coatings contact the part, and what process chemicals transfer during molding.

Parting line — The line where the two mold halves (A-side and B-side) meet. Parting line location affects: gate placement, ejector pin marks, witness lines, and cosmetic appearance. A well-designed parting line minimizes visible witness marks. See also related guide.

Key Facts

  • applies to the final article, not the mold — but the mold is a contamination pathway: steel alloys, surface treatments, mold releases and lubricants can all transfer restricted substances to the part.
  • Hexavalent chromium is the classic mold concern: some steel heat treatments and surface coatings use Cr(VI), which is restricted — the mold maker must specify Cr(III) or -compliant alternatives.
  • Compliance is documentation: the mold maker provides material declarations for steel, coatings and process chemicals, with substance concentrations below thresholds (typically 0.1% for most, 0.01% for cadmium).

    • Parting line — The line where the two mold halves (A-side and B-side) meet. Parting line location affects: gate placement, ejector pin marks, witness lines, and cosmetic appearance. A well-designed parting line minimizes visible witness marks. The related guide covers adjacent topics.

    Where Risks Live in the Mold

    Material or Process Risk
    Mold steel Alloying elements — most tool steels are compliant, but free-machining steels with lead additions are restricted
    Heat treatment Some processes use hexavalent chromium salts — -compliant alternatives use trivalent chromium or other chemistries
    Surface coatings Chrome plating, nitriding and PVD coatings must be specified as -compliant; some traditional chromate conversions contain Cr(VI)
    Mold releases Silicone and fluoropolymer releases must be verified; some legacy formulations contained restricted substances
    Lubricants and cleaners Anything that contacts the part surface must be declared; heavy-metal-containing lubricants are excluded

    The Mold Maker’s Compliance Package

  • Steel declarations: alloy composition certificates showing restricted substances below thresholds — most tool steels comply by default, but free-machining grades require verification.
  • Heat treatment records: process chemistry documentation confirming Cr(III) or compliant alternatives, not Cr(VI) salts.
  • Coating specifications: PVD, nitride or chrome plating with -compliant chemistry — the coating supplier’s declaration feeds the mold maker’s package.
  • Process chemical declarations: mold releases, lubricants and cleaners with substance data sheets showing compliance.
  • Lot traceability: which materials went into which tool, so compliance is traceable to the specific mold, not just a generic statement.

    • How This Shapes Material Selection

    compliance is not a post-build audit; it is a material selection decision made before the steel is ordered. The mold maker specifies -compliant grades, coatings and process chemicals from the start — the quotation names the compliant materials, and the compliance package is the documentation that proves the specification was met.
    When the program requires compliance, the quotation should state which materials are declared compliant and what documentation the mold maker provides — steel certificates, coating declarations and process chemical data sheets — so the compliance package arrives with the tool, not as a discovery after the first OEM audit.

    Frequently Asked Questions

    Does the mold itself need to be ?

    No — applies to the final article sold into electrical and electronic equipment. The mold is a manufacturing tool, not the product. But the mold is a contamination pathway: if the mold introduces restricted substances into the part, the part fails . The mold maker’s obligation is ensuring their materials and processes do not contaminate the part.

    What about — is that different?

    Yes — (Registration, Evaluation, Authorization and Restriction of Chemicals) is the EU’s broader chemical regulation covering thousands of substances, not just six. compliance requires substance declarations for all materials, with restrictions on Substances of Very High Concern (SVHCs). Many -compliant materials also meet , but the two are separate requirements with separate documentation.

    How often does compliance need re-verification?

    When materials change — new steel lot, different coating supplier, reformulated mold release. The mold maker’s lot traceability system tracks which materials went into which tool, so compliance re-verification is triggered by material changes, not calendar dates. Programs with long production runs audit compliance annually or when regulations update.

    Key Takeaways

    1. restricts six substances in electronic articles; the mold is a contamination pathway, so mold materials and process chemicals must be verified compliant.
    2. The mold maker’s deliverable is documentation: steel certificates, heat treatment records, coating declarations and process chemical data sheets — proving the specification was met.
    3. Compliance is a material selection decision made before steel is ordered; the quotation should name compliant materials and specify the documentation package.

    Send aCatMould your requirements, and the quotation specifies compliant materials — steel, coatings and process chemicals — with the documentation package (certificates, declarations and data sheets) scoped as a deliverable, so compliance arrives with the tool, not as a post-build discovery.

    Sources
    EU Directive — substance restrictions and thresholds
    MoldMaking Technology — compliant materials in tooling
    Plastics Technology — and compliance in molding

    Sources: Plastics Technology · Plastics Technology Online · Society of Plastics Engineers (SPE) · ThomasNet