Overview
ISO 9117-2:2010 - Paints and varnishes - Drying tests - Part 2: Pressure test for stackability - specifies a reproducible laboratory method to determine whether a single-coat film or a multi-coat paint system, after a given drying period, is sufficiently dry to resist damage when two painted surfaces (or a painted surface and another surface) are brought into contact under pressure. The method simulates real-world conditions such as stacking painted articles and is sometimes referred to as a “block resistance” or stackability pressure test.
Key topics and technical requirements
- Scope and purpose: Verifies resistance to unwanted adhesion or surface damage when painted items are stacked.
- Standard conditions: Tests are carried out at standard temperature (23 ± 2) °C and ambient relative humidity (RH is measured and recorded according to ISO 3270).
- Sampling & preparation: Sampling in accordance with ISO 15528; panel preparation per ISO 1513 and substrate selection per ISO 1514.
- Test specimens: Cut at least six strips, typically (30 ± 1) mm wide and ≈5× length, with overlap at 90° to create the contact square.
- Apparatus: Plunger with a head diameter of (50 ± 1) mm, plunger mass (250 ± 2) g, optional ball-joint alignment, and additional weights (100 g to 1 000 g) to achieve the specified load.
- Procedure: Place overlapping strips under the plunger, apply the combined mass for the agreed contact time, then separate and examine for impressions, sticking or detachment.
- Pressure calculation: Pressure on the contact area is calculated from the masses and contact square width (formula provided in the standard).
- Reporting: Test report must include product identification, coating preparation and thickness (ISO 2808), RH during test, load/pressure, contact duration, elapsed time before examination, results and any anomalies.
- Precision: No interlaboratory precision data are provided in this edition.
Applications and users
- Practical use: Predicts stackability and block resistance of coatings used on appliances, furniture, metal components, cans, and other painted goods that may be stacked or come into contact in storage, transport or assembly.
- Typical users:
- Coating manufacturers and R&D labs
- Quality control and production engineers
- Suppliers specifying performance for packaging, automotive trim, appliances, furniture and industrial parts
- Test laboratories performing conformity testing and comparative evaluations
Related standards
- ISO 9117 series - Drying tests:
- Part 1: Determination of through-dry state and through-dry time
- Part 3: Surface-drying test using ballotini
- Other parts under preparation (mechanical recorder, modified Bandow-Wolff)
- Cross-references: ISO 1513, ISO 1514, ISO 2808, ISO 3270, ISO 15528
Keywords: ISO 9117-2:2010, stackability test, pressure test, block resistance, paint drying tests, paints and varnishes, coating stackability, test panels, plunger apparatus.