Intertherm 891 Heat-resistant Coating is a heat-resistant paint. As a heat-resistant coating, it is used for general on-site applications, or as an industrial maintenance coating for steelwork at ambient temperature and up to 315°C (600°F) (an economical aluminium topcoat is required). Suitable for all types of operations (including refineries, offshore installations, power stations, petrochemical and chemical plants). A one-component high-temperature paint: an air-drying oil-based resin containing aluminium flakes. Ensure the inorganic zinc primer has fully cured in accordance with the curing conditions specified in the relevant product data sheet before Intertherm 891 is applied. Parameters on this page: dry film thickness 15–25 µm (0.6–1 mil), theoretical spreading rate 19.20 m²/L, number of components one-component.
Parameter source: AKZONOBEL manufacturer's Technical Data Sheet (TDS) "Intertherm 891 Heat-resistant Coating"; values such as spreading rate are converted from TDS parameters and are for product 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 | 48% |
|---|---|
| Dry Film Thickness | 15–25 µm (0.6–1 mil) |
| Theoretical Spreading Rate | 19.20 m²/L |
| VOC | 3.50 lb/gal (420 g/L) US EPA Method 24 456… |
| Density / Specific Gravity | 1.00 kg/L (8.3 lb/gal) |
| Number of Components | One-component |
| Flash Point | 43°C (109°F) |
| Thinner | International GTA004 shall not exceed the limits permitted by local regulations… |
| Mixing Ratio | N/A |
For more Q&A on selection, application, acceptance and defect diagnosis, seeFAQsection.
A one-component high-temperature paint: an air-drying oil-based resin containing aluminium flakes.
As a heat-resistant coating, for general on-site applications, or as an industrial maintenance coating for steelwork at ambient temperature and up to 315°C (600°F) (an economical aluminium topcoat is required.
Suitable for all types of operations (including refineries, offshore installations, power stations, petrochemical and chemical plants).
| Colour | Aluminium INTERTHERM 891 |
|---|---|
| Gloss | N/A |
| Volume Solids | 48% |
| Typical thickness | Dry film thickness 15–25 µm (0.6–1 mil) corresponds to wet film thickness 31–52 µm (1.2–2.1 mil) |
| Theoretical Spreading Rate | At 25 µm dry film thickness and the stated volume solids, 19.20 m²/L; at 1 mil dry film thickness and the stated volume solids, 770 ft²/US gal |
| Practical Spreading Rate | Allowing for a suitable loss factor |
| Application Methods | Suitable for airless spray, air spray, brush, roller. Drying time; recommended topcoat recoat interval |
| Temperature | Surface Dry | Hard Dry | Minimum | Maximum |
| 5°C (41°F) | 18 h | 72 h | 24 h | Unlimited¹ |
| 15°C (59°F) | 12 h | 36 h | 24 h | Unlimited¹ |
| 25°C (77°F) | 8 h | 24 h | Unlimited¹ | |
| 40°C (104°F) | 5 h | 16 h | Unlimited¹ | |
¹ See Definitions and Abbreviations from the International Paint Protective Coatings division.
| Flash point (typical) | 43°C (109°F) |
|---|---|
| Product weight | 1.00 kg/L (8.3 lb/gal) |
| Volatile Organic Compounds | 3.50 lb/gal (420 g/L) US EPA Method 24; 456 g/kg EU solvent emissions directive content (Council Directive 2010/75/EU); coating hazard GB 30981.2-S-Pb≤1000-NC compliant with GB 30981.2-2025; for further details, refer to the section on "Product Characteristics" |
All surfaces to be coated must be clean, dry and free of contaminants. Before application, all surfaces must be assessed and prepared in accordance with ISO 8504:2019.
Primer-precoated surfaces: Intertherm 891 may be applied over approved anti-corrosive primers. The primer surface shall be dry and free of all contamination; Intertherm 891 must be applied within the specified recoat interval (refer to the relevant product data sheet).
Areas of rupture or damage shall be prepared to the specified standard (e.g. abrasive blast cleaning to Sa2½ (ISO 8501-1:2007) or SSPC-SP10, or power tool cleaning to SSPC-SP11), and the primer shall be repaired before Intertherm 891 is applied..
Substrates precoated with zinc-rich primer: Intertherm 891 is suitable for application over zinc silicate shop primer coatings on steel structures. If the zinc primer shows extensive or widely scattered breakdown, or excessive zinc corrosion products, overall sweep blasting is necessary. Other types of pre-primer are not suitable for recoating and require complete removal by abrasive blast cleaning. Welds and damaged areas shall be blast cleaned to Sa2.5 (ISO 8501-1:2007) or SSPC-SP10.
| Mixing | This product is a single-component coating; stir thoroughly with a power mixer before each use |
|---|---|
| Mixing ratio | N/A |
| Suitable for airless spray | Recommended nozzle diameter 0.33–0.41 mm (13–16 mil); total paint pressure at the nozzle not less than 112 kg/cm² (1593 psi) |
Recommended
| Air Spray | Spray gun | DeVilbiss MBC or JGA |
| (with pressure pot) | Air nozzle | 704 or 765 |
| Nozzle | E |
| Brush | Suitable — for small-area touch-up only. Typical thickness 15–25 µm (0.6–1.0 mil) |
|---|---|
| Roller application | Suitable — for small-area touch-up only. Typical thickness 15–25 µm (0.6–1.0 mil) |
| Thinner | International GTA004; thinning shall not exceed the limits permitted by local regulations. |
| Cleaner | International GTA004 |
| Interruption of work | Flush all equipment thoroughly with International thinner. All unused paint shall be stored in closed containers. After a period of storage, skinning may occur in partly filled containers and the viscosity may increase. Strain the paint before use. |
| Cleaning | All equipment shall be cleaned with International thinner immediately after use. Periodic flushing of spray equipment during application is also recommended. The frequency of cleaning depends on the quantity sprayed, temperature and time, including all interruptions. |
Surplus paint and empty containers must be disposed of in accordance with the relevant regional regulations.
Lamellar aluminium pigment is used in the formulation, imparting heat resistance and corrosion resistance and retarding the ingress of atmospheric oxygen. As this is an air-drying system that cures by atmospheric oxidation, excessive film thickness will severely hinder curing.
For maximum temperature resistance, a dry film thickness of 15 µm (0.5 mil) should be applied, since volatilisation of the heat-sensitive organic material causes defects in thick films, including blistering.
Excessive coating thickness of Intertherm 891 extends the minimum recoat time and handling time and adversely affects long-term recoatability.
Excessive coating thickness of Intertherm 891 leads to blistering at high temperature. Gloss and surface smoothness depend on the application method. Mixing several application methods should be avoided wherever possible.
For maximum corrosion resistance, a zinc silicate primer should be used. Mist coating may be required to prevent pinholes. Recoating should preferably be carried out before the zinc silicate weathers; where this is not possible, the zinc silicate surface shall be clean and free of zinc salts.
When applying Intertherm 891 as a topcoat over inorganic zinc primer, application shall strictly follow the film thickness specified in the coating system, as excessive film thickness will cause blistering. Ensure the inorganic zinc primer is fully cured in accordance with the curing conditions specified in the relevant product data sheet before application of Intertherm 891.
Alternatively, Interzinc 890 zinc dust graphite primer may be specified. This product does not provide the extremely high corrosion resistance of zinc silicate, but it tolerates a lower degree of surface preparation, which suits maintenance programmes.
The maximum continuous dry heat resistance of Intertherm 891 is 315°C (600°F). For temperatures above 315°C (600°F), Intertherm 50 shall be used.
Intertherm 891 may be recoated with a wide range of products, including: Intertherm 891 is not designed for continuous immersion in water.
For general-purpose use, aluminium paint Intertherm 891 may be used to recoat all tightly adherent, clean alkyd systems.
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.
At continuous dry temperatures up to 100°C the recommended primer system is: Interprime 198. At continuous dry temperatures up to 315°C the recommended primer systems are: Intertherm 890, Interzinc 12, Interzinc 22, Interzinc 250. For other suitable primers, 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. |
|---|
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 | ||
| Volume | Packaging | |
| 5 L | 5 L | |
| 20 L | 20 L |
For other packaging sizes, contact AkzoNobel.
Packaging Specifications
| 5 L | 5.3 kg |
|---|---|
| 20 L | 21.3 kg |
| Shelf life | 24 months at 25 °C, after which inspection is required. Store in a dry, cool place away from heat sources and ignition sources. |
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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.
Factory product codes for Intertherm 891 Heat-resistant Coating are listed below.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 |
|---|---|---|
| HTA002 Aluminium | — | 4.8//10 L |
This model has a total of1item 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.
