Quantifying Dual Use Additive Migration Limits for Food Contact Compliance Files
Compliance files require measuring migration against specific limits, adjusting for dual-use direct food additive allowances, and verifying raw material data.
Masterbatch Disclosure
Meaning
Detailed documentation of the chemical identity and concentration of additives, pigments and carrier resins used in a polymer concentrate represents a necessary compliance record in high-performance moulding. This document, known as masterbatch disclosure, is demanded by brand owners to ensure that the final product does not contain hazardous substances. It acts as a bridge between the compounder and the moulder, providing the information needed to verify food contact safety or medical grade compliance.
The record is restricted to authorized parties to protect the proprietary recipes of the masterbatch producer.
Formulation Detail
Carrier resins in the concentrate must be compatible with the base polymer to avoid processing defects. In a typical masterbatch disclosure, the specific grade of polyethylene or polypropylene used as the carrier is stated. This enables the moulder to evaluate whether the carrier will alter the melt flow index of the main material.
When incompatible carriers are introduced, they can cause delamination or reduced impact strength in the moulded part.
Regulatory Compliance
Global regulations require full transparency for plastic parts that enter into contact with food or medical devices. The masterbatch disclosure lists the chemical abstract service numbers of all substances that are subject to migration limits or specific bans. Compliance with regulations like REACH or RoHS is verified through these documents.
Without such data, the processor cannot certify the safety of the final product to end users.
Technical Verification
Verification of the additive concentration allows the moulder to set accurate dosage limits on the factory floor. If a masterbatch disclosure indicates a high concentration of an active ingredient like a UV stabilizer or slip agent, the feeder must be calibrated to avoid over-dosing, which is both expensive and detrimental to the mechanical properties of the part. Over-dosing can lead to migration of the additive to the surface, causing cosmetic defects or adhesion failures during labeling.
Moulders use this information to maintain process consistency and control the final properties of the polymer. In addition, the disclosure reveals if there are any processing aids that could interfere with downstream operations such as printing and welding.