General processing information
Water based paints may be the right choice for many applications if the following points are observed:
- Painting tools should be rustproof and parts that come into contact with material must be made of stainless steel.
- The nozzle size, atomizer air cap, material guidance systems, and the spray equipment should be adapted to the water-carrying paints. The compressed air supply for the spray equipment should comprise technically pure air.
- Units that are used alternately with solvent-based laquers should be cleaned carefully and wetted with UN-894 lacquer. Dried paint residues are dissolved with Aqua RK-898 cleaning concentrate.
- The air and material temperature and the parts that need to be coated should be tempered from 18 to 25°C. A temperature of 5°C should not be undercut when water based paints are stored and transported.
- The wood moisture should be 8 - 12% and the relative humidity should be 45 - 65 %.
- To ensure good drying after the flash-off time, we recommend discharging the water vapour escaping from the paint layer with an air current. This method that can be realised using ventilators is frequently adequate for a short drying time.
- Water based paints should only be applied in the stipulated quantities because higher layer thicknesses significantly delays the drying process and can cause surface flaws (heavy swelling of the wood, higher dust inclusions, dry cracks, flow flaws). Remmers Aqua- paints have a higher level of solids than comparable solvent-based laquers and are therefore applied somewhat thinner which means material can be saved.
- Dried paint residues, e.g. on the spout of the packaging, do not dissolve in water based paints. The material always needs to be processed with a suitable sieve.
- The raw wood pulp and intermediate sanding should be finer. The selection of the wood construction materials that need to be coated should be assessed with regard to its swelling behaviour. This especially applies for medium dense fibreboards.
- During the course of the development, Remmers Aqua paints demonstrate greater firing of the wood surface. The dull look of the wet paint film then dries transparently.
- When using the Aqua hardener H-480 in the corresponding water based paints, the pot life needs to be observed in addition to careful mixing by means of a patent disperser (Art.-No. 474701 / 474702) and, if necessary, thinning with water. Mixed material residues may not harden in closed packages.