Overview
EN ISO 22553-16:2023 - Paints and varnishes - Electro-deposition coatings - Part 16: Pigment‑binder ratio (ISO 22553-16:2022) specifies a laboratory test method to determine the pigment‑binder ratio in electro‑deposition coatings (e‑coats). Adopted by CEN without modification, this method is intended for automotive and other industrial applications (chiller units, consumer products, radiators, aerospace, agriculture). The standard defines the measurement principle, required apparatus, sampling and calculation steps used to report the pigment‑binder ratio for process control and quality assurance.
Key topics and requirements
- Scope and applicability: Applies to electro‑deposition coatings used in automotive and general industrial sectors.
- Measurement principle: Determine the ash content (residue on ignition) and the non‑volatile‑matter (NV) content; calculate pigment and binder contents and their ratio.
- Apparatus and sample prep:
- Porcelain high‑form crucible, muffle furnace (or rapid incinerator), oven (105 °C), analytical balance (0.001 g), desiccator and tongs.
- Sampling and sample preparation referenced to ISO 15528 and ISO 1513.
- Procedure summary:
- Ash determination: dry sample, ignite at ~600–900 °C to constant mass; calculate ash percent.
- Apply a product‑specific correction factor (provided by the manufacturer) to convert ash to pigment content.
- NV determination: perform according to ISO 3251 (two heating variations provided).
- Binder content = NV − pigment; pigment‑binder ratio = pigment / binder.
- Reporting and quality:
- Report must include identification, reference to ISO 22553‑16:2022, pigment‑binder ratio, deviations, anomalies and test date.
- Note: precision data are not currently available in the standard.
Practical applications and users
- Who uses it:
- Coating formulators and R&D labs developing e‑coat chemistries.
- Quality control/production labs in automotive OEMs and suppliers to monitor bath composition.
- Independent testing laboratories, certification bodies and regulatory compliance teams.
- Failure analysis teams investigating coating defects related to solids composition.
- Why it matters:
- The pigment‑binder ratio is a key parameter for e‑coat bath control, film properties and consistent corrosion protection, appearance and performance.
- Used for process control, batch acceptance, supplier verification and product development.
Related standards
- ISO 3251 - Determination of non‑volatile‑matter content
- ISO 1513 - Examination and preparation of test samples
- ISO 15528 - Sampling of paints and varnishes
- ISO 4618 - Terms and definitions for paints and varnishes
- ISO 22553‑1 - Electro‑deposition coatings - Vocabulary
Keywords: EN ISO 22553-16:2023, pigment‑binder ratio, electro‑deposition coatings, e‑coat test method, ash content, non‑volatile matter, coating quality control.
