Special Functional Coatings
Dachin VE 742
Acid resistant coating
Composition
A three-component, self-drying, high-solids, thick-film type acid-resistant coating comprising vinyl ester resin, additives, glass flakes, hardener, and accelerator.
Key Characteristics
This vinyl ester glass flake coating exhibits excellent resistance to organic and inorganic acid solutions, as well as many aliphatic solvents. It provides superior chemical resistance, effective barrier protection, rapid drying, ease of application, and quick return to service.
Applications
Widely used for corrosion protection of carbon steel and concrete structures in bridges, offshore facilities, petrochemical plants, chemical plants, pulp and paper mills, and other industrial environments.
Technical Specifications
| Color | Gray, light gray |
|---|---|
| Volume Solids Content (%) | 66.5±1 |
| Density (kg/L) | 1.37±0.02 |
Packaging Specifications
| Weight (kg) | Volume (L) | |
|---|---|---|
| Component A (Base) | 20 | 14.5 |
| Component B (Hardener) | 0.166 | 0.2 |
| Component C (Accelerator) | 0.184 | 0.18 |
| Total | 20.35 | 14.88 |
Basic Parameters
| Mix Ratio | Weight Ratio A:B:C = 20:0.166:0.184 |
|---|---|
| Pot Life | 25°C: 55 minutes; 35°C: 30 minutes |
| Theoretical Coverage | ~6.5 m²/L (based on 100μm dry film) |
Recoat Intervals
| Temperature (°C) | Surface Dry (h) | Hard Dry (h) | Recommended Recoat Interval | |
|---|---|---|---|---|
| Minimum | Maximum | |||
| 10 | 5 | 24 | 12 | 1 week |
| 15 | 4 | 16 | 8 | |
| 25 | 2 | 4 | 4 | |
| 35 | 1 | 3 | 3 | 3 days |
Data derived from standard film thickness on steel test panels.
Application Guide
- Dachin VE 742 Acid-Resistant Coating is a three-component system (base, hardener, accelerator). Strictly follow mixing and application guidelines. Once mixed, it must be applied within the specified pot life. Failure to do so will result in gelation and render the coating unusable. Discard unused mixed coating.
- After application, immediately clean all equipment in contact with Dachin VE 742 using Dachin Thinner X16. Thoroughly flush airless pumps to prevent blockages. Optimal cleaning involves leaving pumps soaked in thinner.
- If recoating beyond the recommended interval, test the surface with styrene. If tacky to the touch, recoating is acceptable. If not softened by styrene, mechanically abrade or sandblast the surface to create a rough profile.
- Typical film thickness: 500μm per coat via airless spray; 100-200μm via brush/roller (multiple coats may be required to achieve desired thickness).
Compatible Coatings
Primer: Dachin VE 380 Acid-Resistant Primer
Surface Preparation
Steel Substrates: Clean steel surfaces of dust and oil. Blast clean to Sa2.5 standard. Avoid excessive roughness to ensure adequate coverage. Weld seams unsuitable for blasting should be power tool cleaned to St3.
Concrete Substrates: Ensure proper curing, cleanliness, and dryness. Remove loose cement paste via grinding before application.
Over Dachin VE 380 Primer: Test surface with styrene to confirm recoatability.
Mixing
This product is supplied in three components (Components A, B, C). Mix strictly by ratio and thoroughly stir with power tools to ensure homogeneity.
Application Methods
| Application Type | Thinner | Dilution (%) | Nozzle Size (mm) | Spray Pressure (kg/cm²) |
| Airless Spray | Dachin Thinner X16 | 0 | 0.69-0.84 | ≥155 at nozzle |
| Roller/Brush | Dachin Thinner X16 | 0-5% | N/A | N/A |
Dilution calculated by paint weight.