Overview
EN ISO 22553-12:2021 (ISO 22553-12:2020) specifies a laboratory method to assess sedimentation of electro‑deposition (e‑coat) coating materials on horizontal areas. The standard defines a reproducible test procedure-using an L‑shaped test panel and a laboratory deposition system-to detect surface defects caused by sedimentation (for example streaks or inclusions) after application and stoving. It is intended for automotive and other industrial applications (chiller units, consumer products, radiators, aerospace, agriculture).
Key topics and technical requirements
- Test principle: Immerse an L‑shaped bent, phosphated test panel in an e‑coat bath, deposit to target dry‑film thickness, rinse, stove and visually evaluate the horizontal surface that was facing upward during deposition.
- Test specimen: L‑panel bent (90 ± 5)° with horizontal surface width (70 ± 5) mm.
- Apparatus and controls:
- Laboratory deposition tank with recirculation and DC power supply.
- Stirring: homogenize bath with a paddle stirrer (diameter ≥ 50 mm) at about 500 min⁻¹ to ensure visible circulation.
- Temperature control: bath set to product‑specific temperature to ±0.5 °C (typical range 25–35 °C).
- Oven stability: ±2 °C up to 150 °C; ±3.5 °C between 150–200 °C.
- Measurement instruments: film‑thickness device (max error 0.1 µm), thermometer (0.1 °C), timer (1 s).
- Deposition parameters: Select voltage and time to achieve the e‑coat’s nominal dry‑film thickness; maintain selected voltage during application.
- Evaluation: Visual assessment of the horizontal area using the ISO 4628‑1:2016 intensity scale (rating 0 to 5).
- Reporting: Must include identification of coating, reference to ISO 22553‑12:2020, tank voltage and temperature, application times, stoving conditions, measured dry‑film thickness and method, test result (rating), deviations and anomalies, and test date.
- Precision: No precision data currently available (as stated in the standard).
Applications and users
- Who uses it: Paint/formulation laboratories, quality control teams in automotive OEMs and suppliers, industrial e‑coat manufacturers, coating R&D groups, third‑party testing labs.
- Why use it: To screen e‑coat formulations and process parameters for sedimentation‑related defects on horizontal surfaces, support quality assurance, compare materials, and reduce field failures on parts with horizontal geometries.
Related standards
- ISO 2808 - determination of film thickness
- ISO 4618 - paints and varnishes terms and definitions
- ISO 22553‑1 - electro‑deposition coatings vocabulary
- ISO 23321 - demineralized water for industrial applications
- ISO 4628‑1 - evaluation scale for coating appearance changes
Keywords: EN ISO 22553-12:2021, electro-deposition coatings, sedimentation test, e-coat, horizontal areas, L-panel, film thickness, automotive coatings, laboratory deposition system.