Overview
ISO 7142:2023 - Binders for paints and varnishes - Epoxy resins - General methods of test - specifies general test methods for epoxy resins and epoxy-resin solutions intended as binders for paints and varnishes. It defines required tests, sampling reference, and the minimum content of test reports. The standard explicitly excludes epoxy esters.
Key topics and technical requirements
- Scope & applicability
- Applies to epoxy resins used in paints, varnishes and similar products, including resin solutions used as binders.
- Not intended for epoxy esters.
- Sampling
- Requires a representative sample taken in accordance with ISO 15528 (sampling of paints, varnishes and raw materials).
- Mandatory test properties (Table 1)
- Annex A - Hydroxyl value
- Provides reagents, apparatus and titration procedure to determine hydroxyl equivalent and express hydroxyl value (g KOH/kg).
- Precision: repeatability ~10%, reproducibility ~20%.
- Test report content
- Must include product ID, reference to ISO 7142:2023, test results and methods, deviations, anomalies and test dates.
Practical applications and users
ISO 7142:2023 is designed for practical quality control, specification and communication across the paint, coatings and resin supply chain. Typical users:
- Coating manufacturers and formulators verifying binder quality before production.
- Raw material suppliers specifying epoxy resin properties for commercial data sheets.
- QC/analytical labs performing standardized tests (epoxy equivalent, hydroxyl value, viscosity, colour, chlorine content, flash point).
- Procurement and specification engineers who need reproducible test methods to compare materials or enforce purchase specifications.
Using ISO 7142:2023 ensures consistent, comparable data on critical binder properties and supports regulatory, safety and performance assessments in coatings formulation.
Related standards
Commonly used normative references cited in ISO 7142:2023 include:
Keywords: ISO 7142:2023, epoxy resins, binders for paints and varnishes, test methods, hydroxyl value, epoxy equivalent, paint binder testing.
