TEKNODUR 295-900
High solids polyurethane clear coat
- UV resistant
- 2-component
- Solvent-borne
- Clear coat
- Topcoat
- UV resistant
- 2-component
- Solvent-borne
- Clear coat
- Topcoat
TEKNODUR 295-900 is a two pack, ready to use polyurethane clear coat.
TEKNODUR 295-900 is a high end full gloss clear coat providing excellent UV resistance, improving the gloss and color retention of TEKNODUR Polyurethane Coating Systems. The coating gives a high quality finish with excellent mechanical durability and elasticity to ensure a long-lasting finish. TEKNODUR 295-900 is an optimal solution for surfaces that are subjected to heavy stresses, yet still requiring a long-lasting finish. Main field of applications are within commercial and rail vehicle manufacturing as well as any other industry desiring a high end full gloss finish. TEKNODUR 295-900 has good chemical resistance, withstanding washing and cleaning chemicals commonly used on e.g. railroad and transportation equipment.
Surface preparation
Remove from the surfaces any contaminants that might be detrimental to surface preparation and application. Remove also water-soluble salts by using appropriate methods. The surfaces are prepared according to the different materials as follows:
OLD PAINTED SURFACES SUITABLE FOR OVERCOATING: Any impurities that might be detrimental to the application of paint (e.g. grease and salts) are removed. The surfaces must be dry and clean. Old, painted surfaces that have exceeded the maximum overcoating time are to be roughened as well. Damaged parts are prepared in accordance with the requirements of the substrate and the maintenance coating.
The place and time of the preparation are to be chosen so that the prepared surface will not get dirty or damp before the subsequent treatment.
Additional instructive information for surface preparation can be found in standards EN ISO 12944-4 and ISO 8501-2.
Application
Take into consideration the pot life of the mixture when estimating the amount to be mixed at a time. The base must be stirred until it is homogeneous before mixing the components. Before application the base and hardener are mixed in right proportion. Stir thoroughly down to the bottom of the vessel. Inadequate stirring or incorrect mixing ratio results in imperfect curing and impaired film properties.
Stir thoroughly before use. Before use clean the spray gun and paint vessels with a thinner suitable for the paint.
Suitable air-assisted airless nozzle size 0.009 - 0.012". Suitable conventional spray nozzle size 1.2 - 1.4 mm. The recommended application viscosity is 16 - 22 s DIN 4.
Dilute the clear coat 0 - 5%, when required. Dilution of 10 - 15% may be required when applying lower dry film thicknesses. With 5 - 15% dilution, application of the clear coat in 1.5 - 2 layers (wet-on-wet) is possible.
Suitable thinners:
Fast thinner: TEKNOSOLV 9526. Used when spray painting large surfaces with mist coating technique.
Slow thinner: TEKNOSOLV 9521. Used e.g. when painting large surfaces and when the temperature is above room temperature.
Do not use universal thinners, since they may contain alcohol which will react with the hardener.
Application conditions
The surface to be treated must be dry. During the application and drying period the temperature of the ambient air, the surface and the product shall be above +5°C and the relative air humidity below 80%. Additionally, the temperature of the surface to be treated and the product must be at least +3°C above the dew point of the ambient air.
Storage
The storage stability is shown on the label. Store indoors in a cool and dry place and in a tightly closed can. The hardener reacts with air humidity and therefore the opened can is to be kept carefully closed, and it is recommended to be used within 14 d of opening.
| Total mass of solids | abt. 565 g/l |
|---|---|
| Volatile organic compound (VOC) | abt. 435 g/l |
| Pot life | 1,5 h (+23 °C) |
| Mixing ratio | 4:1 by volume (comp. A : comp. B) |
| Hardener | Comp. B: TEKNODUR HARDENER 7295 |
| Gloss | Full gloss |
| Practical spreading rate | The values depend on the application technique, surface conditions, overspray, etc. |
| Drying time – dust free | 1.5 h (ISO 9117-3:2010) |
| Drying time – touch dry | 7 h (ISO 9117-5:2012) |
| Thinner | The product is delivered ready for use. Suitable thinners and application viscosities see Application. |
| Clean up | TEKNOCLEAN 6496 |
| Colours | Clear. |
| Safety markings | See safety data sheet. The hardener of the product and the ready mixture contain isocyanates. In poorly ventilated areas and especially when using spray application we recommend the use of a fresh air mask. In short or temporary work, a mask with combined filter A2-P2 can be used. In this case eyes and face are to be protected. The hardener can must be opened with caution, as pressure may develop in the can during storage. |
| Gloss value | 90- |