Greige Fabric Certification Scope and Restricted Chemical Testing Protocols
Greige fabric certification demands batch testing of sizing agents, spin finishes, and biocide residues before finishing treatments mask regulated chemicals.
Total Metal Digest
Elemental Recovery
Complete mineralization ensures that all metallic components within a textile matrix are fully released for concentration measurement. A total metal digest differs from a migration test because it uses strong acids and high heat to destroy the fiber structure entirely. This method reveals the absolute quantity of metals present, including those locked deep within synthetic polymers or pigments.
Digestive Chemistry
Microwave-assisted systems provide the pressure and temperature needed for a fast and efficient reaction. During a total metal digest, the sample is typically treated with concentrated nitric or hydrochloric acid until the solution becomes transparent. This liquid is then diluted and filtered to prepare it for instrumental analysis.
Compliance Standard
Global regulations for heavy metals often specify this destructive method to ensure no hidden contaminants are overlooked. Results from a total metal digest provide a worst-case scenario of the metallic load in a product. It is the preferred method for verifying compliance with the most stringent environmental and safety requirements.
This rigorous approach prevents the accidental release of goods that might leach harmful elements under extreme conditions.
Sample Homogeneity
Grinding the textile into a fine powder before the reaction ensures that the small test portion is representative of the whole garment. A successful total metal digest eliminates any variance caused by the physical shape or thickness of the material.