Paints and varnishes - Determination of resistance to liquids - Part 1: Immersion in liquids other than water
1Key Takeaways
This document specifies general methods for determining the resistance of an individual-layer or multi-layer system of coating materials to the effects of liquids, other than water, or paste-like products (included implicitly in test liquids mentioned in the text). These methods enable the testers to determine the effe…
2Expert Interpretation
This in-depth analysis of the coating liquid resistance test method in ISO 2812-1:2017 covers the single-phase and dual-phase liquid immersion test process, evaluation criteria, and implementation points, providing professional testing solutions for industries such as automotive coatings.
Test Method Comparison
| Dimensions | Method A (Single-Phase Liquid) | Method B (Two-Phase Liquid) |
|---|---|---|
| Applicable Scenarios | Single Chemical Reagent Test | Immiscible Liquid Interface Test |
| Immersion Method | Vertical Half Immersion (Default) | 40%+40% Layered Immersion |
| Conductive Liquid Requirements | Must maintain a 30mm spacing | Must prevent liquid cross-contamination |
Key Technical Requirements
Test Sample Preparation
The standard specifies the use of an ISO 1514 standard plate measuring 150mm × 100mm × (0.7-1.0)mm or a 15mm diameter steel rod. Coating thickness must be measured according to ISO 2808 and must be conditioned for 16 hours at 23±2°C and 50±5% RH before testing.
Typical Test Fluids
- Automotive Industry: Diesel according to EN 590, gasoline according to EN 228, FAM test fluid according to DIN 51604
- Chemicals: 10% hydrochloric acid (CAS 7647-01-0), 5% sodium hydroxide (CAS 1310-73-2)
Implementation Recommendations
- Edge Effect Control: It is recommended to use steel bar specimens or protect the edges of the plate
- Temperature Control: Preheat the liquid for high temperature testing and maintain an accuracy of ±3°C
- Evaluation Points: Assess the degree of blistering according to ISO 4628-2. After testing, allow 24 hours for equilibration and retest.
- Safety Warning: Volatile flammable liquids must be handled in an explosion-proof environment.
Standard Evolution Analysis
Compared to the 2007 edition, the 2017 edition primarily adds a new CAS numbering system for reagents and strengthens the standardization of term definitions. The test methods continue the core framework of the previous edition but refine the electrical isolation requirements for testing conductive liquids.