Pre-treatment
The substrate must be free from oil, grease and oxidation products. The pretreatment depends on the type of substrate and the corrosion protection to be achieved. We recommend the following pretreatments:
Aluminium
- Chrome-free pretreatment according to GSB International and QUALICOAT specifications
- Chromating according to DIN EN 12487
- Pre-anodization
Steel
- Blasting: Electro corundum or conditioned cut wire shot should be used. After blasting, the norm purity degree must be at least SA 2 ½ (white metallic polish) in accordance with DIN EN ISO 12944-4. Further details can be found in this norm. Sharp edges, overlaps, etc., should be avoided (see DIN EN ISO 12944-3).
Galvanised steel
- Zinc phosphating
- Chrome (III) passivation
- Chromating according to DIN EN 12487
The suitability of the pretreatment method used is generally to be tested by the coater in advance with appropriate test methods. The minimum requirement for aluminium substrates / galvanised steel components is to carry out a boiling water test with a subsequent cross-cut adhesion and tape test. We refer to the guidelines of the GSB International, Qualicoat and Qualisteelcoat certifications. For further information: see also our special leaflet on pre-treatment (IGP-TI 100).
Coating devices
All commercially available electrostatic systems, both corona and tribo charge systems.
For the construction and operation of powder coating plants, the following regulations must be complied with: ATEX RL 2014/34/EU, EN 50177, DIN EN 16985.
Recommended film thickness
60 μm - 100 μm
A homogeneous coating result with textured paints or colour or article-specific differences in hiding power may require higher Film thicknesses. The corresponding processing guidelines must be observed.
For a preliminary calculation of the required powder coating quantity, the required Film thickness must be determined for each specific article.
Curing conditions
| TObject | t min | t max |
|---|
| 170 °C | 15 minutes | 20 minutes |
| 180 °C | 10 minutes | 15 minutes |
| 190 °C | 8 minutes | 12 minutes |
When curing thick steel components we recommend to gel the primer and fully cure the part with the top coat.
To avoid intercoat adhesion problems the maximum air temperature should be limited to 200°C.
When curing in directly heated gas ovens, a sample should be done in advance to ensure the intercoat adhesion with the following top coat.
Please contact our technical customer support.
In order to determine ideal curing conditions, we recommend practical trials with the respective object and curing oven.
Application
Please follow the application guideline VR211.
Reclaimability
Small portions of recycled powder can be added, automatically if possible, to the fresh powder. Important: Keep overspray to an absolute minimum.
