Intertherm 228HS Epoxy Phenolic High-temperature Paint is a heat-resistant paint, an epoxy coating system. Suitable for various highly corrosive environments, including: insulated and uninsulated steel, and the external walls of pipelines and process vessels with operating temperatures up to 230 °C (446 °F). A high-crosslink, two-component, high-build epoxy phenolic coating with good anti-corrosion and chemical resistance under high-temperature conditions. If Intertherm 228HS is used for maintenance, it is recommended to apply three coats, each 65 µm (2.5 mils), with a total dry film thickness of 195 µm (7.5 mils). Parameters on this page: dry film thickness 100–150 µm (4–6 mils), theoretical spreading rate 4.67 m²/L, number of components: two.
Data source: AKZONOBEL original Technical Data Sheet (TDS), "Intertherm 228HS Epoxy Phenolic High-temperature Paint"; spreading rate and other values are converted from the TDS parameters, for selection reference only.
The above content is compiled from the manufacturer's datasheet and this site's parameter tables. For selection, coating systems and lead times, pleaseContact Usfor confirmation.
This page carries the full TDS for this product, translated from the manufacturer's original document. No file download is needed; for an original-language copy, send an enquiry.
| Volume Solids | 70% |
|---|---|
| Dry Film Thickness | 100–150 µm (4–6 mils) |
| Theoretical Spreading Rate | 4.67 m²/L |
| VOC | 2.21 lb/gal (265 g/L) US EPA Method 24 16… |
| Density / Specific Gravity | 1.86 kg/L (15.5 lb/gal) |
| Number of Components | Two-component |
| Thinner | Normally no thinning is required |
| Mixing Ratio | 6 parts : 1 part (by volume) |
| Colour / Appearance | Limited range, INTERTHERM 228HS |
For more Q&A on selection, application, acceptance and defect diagnosis, seeFAQsection.
A high-crosslink, two-component, high-build epoxy phenolic coating with good anti-corrosion and chemical resistance under high-temperature conditions.
Intertherm 228HS is a next-generation epoxy phenolic coating based on phenolic resin (Novolac) technology.
Intertherm 228HS is specially designed to provide an anti-corrosion barrier, protecting steel structures under insulation in alternating wet and dry areas.
Suitable for various highly corrosive environments, including: insulated and uninsulated steel, and the external walls of pipelines and process vessels with operating temperatures up to 230 °C (446 °F).
Intertherm 228HS exhibits excellent thermal cycling crack resistance in rapid temperature cycling.
| Colour | Limited range, INTERTHERM 228HS |
|---|---|
| Gloss | Sheen |
| Volume Solids | 70% |
| Typical thickness | Dry film 100–150 µm (4–6 mils), equivalent to wet film 143–214 µm (5.7–8.6 mils) |
| Theoretical Spreading Rate | At 150 µm dry film thickness and the stated volume solids, 4.67 m²/L; at 6 mil dry film thickness and the stated volume solids, 187 sq ft/US gal |
| Practical Spreading Rate | Allowing for a suitable loss factor |
| Application Methods | Suitable for airless spray, air spray, brush, roller. Drying time; self-recoat interval |
| Temperature | Surface Dry | Hard Dry | Minimum | Maximum |
| 10°C (50°F) | 8 h | 28 h | 36 h | 5 days |
| 15°C (59°F) | 7 h | 16 h | 24 h | 4 days |
| 25°C (77°F) | 5 h | 8 h | 16 h | 3 days |
| 40°C (104°F) | 2 h | 4 h | 16 h | 3 days |
| Flash point (typical) | Component A 28 °C (82 °F); Component B 55 °C (131 °F); mixed 30 °C (86 °F) |
|---|---|
| Product weight | 1.86 kg/L (15.5 lb/gal) |
| Volatile Organic Compounds | 2.21 lb/gal (265 g/L) US EPA Method 24; 167 g/kg EU Solvent Emissions Directive content, Commission Directive 2010/75; 275 g/L China national standard GB 23985. Coating hazardous substances: GB 30981.2-S-Pb≤1000-NC compliant with GB 30981.2-2025. For more details, see the "Product Characteristics" section. |
All surfaces to be coated shall be clean, dry and free from contamination. Before painting, all surfaces shall be assessed and prepared in accordance with ISO 8504-1. Where necessary, remove weld spatter and grind welds and sharp edges smooth. Oil and grease shall be removed in accordance with SSPC-SP1 solvent cleaning.
Blast cleaning: this product must be applied only over surfaces abrasive blast cleaned to a cleanliness of Sa 2.5 (ISO 8501-1:2007) or SSPC-SP10, with a recommended sharp angular surface roughness of 50–75 µm (2–3 mils). Intertherm 228HS must be applied before the steel oxidises. If oxidation has occurred, the entire oxidized area should be re-blasted to the specified standard.
Surface defects found during blasting must be ground, filled or treated by a suitable method.
Power tool cleaning (for small areas only): the product is suitable for application over surfaces power tool cleaned to at least SSPC-SP11. Note that all mill scale must be removed; all areas that cannot be adequately prepared should be locally blasted to the minimum standard of Sa 2 (ISO 8501-1:2007) or SSPC-SP6.
Stainless steel: before coating, ensure the surface is clean, dry and free of metal corrosion products. To obtain an anchor pattern with a surface roughness of about 50 µm (2 mils), use non-metallic, chloride-free abrasive (e.g. aluminium oxide or emery) for light brush-off blasting.
| Mixing | This product is supplied in two containers forming one unit. Mix the two components in the specified ratio in one operation. Once mixed, use within the specified pot life. |
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(1) Stir the base (Component A) with a power mixer.
(2) Mix all of the curing agent (Component B) with the base (Component A) and stir thoroughly with a power mixer.
Avoid prolonged stirring, as the heat generated greatly shortens the pot life.
| Mixing ratio | 6 parts : 1 part (by volume) |
|---|
| Pot life | 10°C (50°F) | 15°C (59°F) | 25°C (77°F) | 40°C (104°F) |
| 5 h | 4 h | 90 min | 45 min |
| Suitable for airless spray | Recommended: nozzle diameter 0.43–0.53 mm (17–21 thousandths of an inch); total paint pressure at the nozzle not less than 176 kg/cm² (2503 psi) |
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| Air Spray | Recommended | Spray gun | DeVilbiss MBC or JGA |
| Air nozzle | 62 | ||
| (with pressure pot) | Spray painting | AC | |
| Brush | Suitable for small areas | Typical thickness 50–75 µm (2.0–3.0 mils) | |
| Roller application | Suitable for small areas | Typical thickness 50–75 µm (2.0–3.0 mils) | |
| Thinner | International GTA220 (or | Normally no thinning is required. |
GTA415) In extreme cases consult the local technical representative.
Do not thin beyond the requirements of local environmental regulations.
| Cleaner | Use a cleaning solvent that complies with local regulations. Consult the local representative for specific recommendations. |
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| Interruption of work | Do not leave paint in hoses, spray guns or spray equipment. Flush all equipment thoroughly with International thinner. |
Mixed paint should not be resealed. If work is interrupted for too long, mix a fresh batch of paint for application.
| Cleaning | Clean all equipment immediately after use with International thinner. Flushing spray equipment periodically during application is recommended. Cleaning frequency depends on the volume sprayed, temperature and time, including all interruptions. |
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Surplus paint and empty containers must be disposed of in accordance with the relevant local regulations.
Intertherm 228HS is generally applied in two coats, each 100 µm (4 mils), with a total system dry film thickness of 200 µm (8 mils).
Care should be taken to avoid over-application, which can cause cracking when the whole coating system serves in high-temperature environments. The total system film thickness should not exceed 350 µm (13.8 mils). To achieve the maximum film thickness in a single coat, airless spray is ideal. The required film thickness cannot be achieved with application methods other than airless spray. With conventional air spray, multiple cross-sprays are required to achieve the maximum film thickness. Brush and roller are recommended only for small areas.
When applying Intertherm 228HS by brush or roller, multiple coats are necessary to achieve the specified total system dry film thickness.
If Intertherm 228HS is used for maintenance, it is recommended to apply three coats, each 65 µm (2.5 mils), with a total dry film thickness of 195 µm (7.5 mils).
The steel substrate surface temperature must be at least 3 °C (5 °F) above the dew point. Application below 10 °C (50 °F) will result in extended drying time. The relative humidity during application and curing should not exceed 80%. When applying Intertherm 228HS in confined spaces, ensure adequate ventilation.
After the final coat has cured and dried, measure the dry film thickness of the coating system with a suitable non-destructive magnetic gauge to check the average total thickness. The coating system shall be free from pinholes and other skips. The cured film shall be free from defects such as runs, sags, drips and inclusions. All defects shall be repaired.
Curing time varies with the dry film thickness and the conditions during application and throughout curing.
Ideal performance is only achieved after the film is fully cured; the degree of cure depends on temperature, humidity and film thickness. Normally, an Intertherm 228HS coating system with a dry film thickness of 300 µm (12 mils) fully cures after 7–10 days at 25 °C (77 °F) to achieve ideal temperature resistance. Curing time shortens at higher temperatures and lengthens at lower temperatures.
Like all epoxies, Intertherm 228HS chalks and "yellows" outdoors. At high temperatures, Intertherm 228HS will also show significant colour changes. However, these phenomena do not affect anti-corrosion performance, provided the recommended temperature range is not exceeded.
Intertherm 228HS is suitable for protecting alternating wet and dry insulated steel structures, with a continuous service temperature range from ambient to below 200 °C (392 °F), and intermittent fluctuation temperatures below 230 °C (446 °F).
Intertherm 228HS is an immersion-resistant epoxy phenolic resin paint, suitable for environments in continuous sealed contact with trapped moisture.
Note: VOC values are typical and for guidance only. They may vary with colour and general production tolerances.
Although the low-molecular-weight reactive additive becomes part of the film when cured under normal ambient conditions, analysis by EPA Method 24 shows that it also affects the VOC value.
This is a self-recoating coating, not suitable for application over other primers.
Intertherm 228HS is normally self-overcoated; for other suitable topcoats, consult International Paint.
| For further information on the industry standards, terms and abbreviations used in this datasheet, see www.international-pc.com | In the following documents on the website: • Definitions and abbreviations • Surface preparation • Coating application • Theoretical and practical spreading rate. These sections are also available as separate publications on request. |
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This product must be applied at the production site by professional applicators in accordance with the recommendations in this manual, the Material Safety Data Sheet and the instructions on the container label. Do not use this product without first reviewing the Material Safety Data Sheet (MSDS) that International Paint provides for its customers.
All work related to the application and use of this product must be carried out in accordance with the relevant national health, safety and environmental standards and regulations.
If welding or flame cutting is required on metal coated with this product, dust and fumes will be generated; use appropriate personal protective equipment and adequate local ventilation.
If in doubt about the suitability of this product for the intended use, consult AkzoNobel for further advice.
| Packaging Specifications | Component A | Component B | ||
| Volume | Packaging | Volume | Packaging | |
| 20 L | 17.14 L | 20 L | 2.86 L | 5 L |
| 5 US gal | 4.29 US gal | 5 US gal | 0.71 US gal | 1 US gal |
For other packaging sizes, contact AkzoNobel.
At 25 °C (77 °F), Component A 12 months, Component B 18 months. Thereafter
| Shipping weight | Packaging Specifications | Component A | Component B |
| 20 L | 35.11 kg | 2.75 kg | |
| 5 US gal | 77.1 lb | 6.5 lb | |
| Storage | Shelf life |
inspect before use. Store in a dry, cool environment, away from heat sources and sources of ignition.
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Information is subject to the manufacturer's latest version; the manufacturer's latest TDS prevails.
The technical parameters on this page are taken from the product's original manufacturer technical datasheet, the copyright of which belongs to the manufacturer. If a rights holder considers the presentation inappropriate, contact us for verification and handling.
Packaging specifications and batch lead times are subject to actual availability. PleaseContact Uscontact us for project-based calculation.
The factory product codes for Intertherm 228HS Epoxy Phenolic High-temperature Paint are as follows.Item No.is the most accurate form when ordering;Colour/colour codecorresponds to the actual colour (RAL, GSB are colour chart codes);Packaging SpecificationsFactory complete-set specification format. Colors not listed may be ordered against the colour card.
| Item No. | Colour / colour code | Packaging Specifications |
|---|---|---|
| HTA542 | White | 17.14 L + 2.86 L |
| HTA541 | Grey | 17.14 L + 2.86 L |
This model has a total of2item numbers, all listed on this page; colours outside the table (including special colours and bulk packaging) can be confirmed by phone, delivery dates are advised according to the factory's current production schedule and stock. In the packaging specification, the "+" indicates the complete-set notation for two-component products (base + curing agent), subject to the factory specification; a "—" in the colour column denotes an auxiliary product, or that the item has no colour code in the factory system.
