Changing from solvent-based to waterbased coatings

Changing from solvent to waterbased coatings

Waterborne woodcoatings become mainstream in the interior and exterior wood industry. Therefore, it is crucial to understand how it differs from solvent-based woodcoating, as well as what you need to do to achieve an excellent surface result and how to protect your employees.

While the transition from solvent-based paint to waterborne may seem expensive, the costs are justified by:

Creating a healthier work environment for painters
Environmental benefits through less emission
Waste and disposal of paint is cheaper (and can be recycled)

The solid contents in waterborne paints is normally higher as solvents and therefore the theoretically yield is higher. So its not adviced to stare blind on liter or kilo prices of the woodcoating itself.

Equipment

When using waterborne coatings, make sure that the paint guns are made of corrosion-resistant materials. Most brands, such as Graco or Wagner Group, already sell this as a standard. Cleaning the paint guns after using waterborne wood coatings is done with water or specific cleaners.

It is strongly advised to not use one pump or pistol for both waterborne and solvent wood coatings. This will cause contamination to the wood coatings, especially when using 2K products.

Drying procedures

Curing time for waterborne wood coatings can be longer than solvent-based coatings when the right climate is lacking and drying settings are not being followed. When you follow the right drying settings then you can even force-cure waterborne coatings with a drying time under 30 minutes.

We always recommend to keep the temperature above 15 degrees, also after working hours and during the night. Ideal would be 19-20 degrees with air circulation. Industrial air fans can be bought at many locations across the United Kingdom. Also companies such as Schuberts offer professional drying tunnels that can increase drying time under 25 minutes.

The best way of force drying is via catalytic infrared heat. The basic technology behind infrared heat, means that the rays of light/heat, penetrates the coating, resulting in curing the coating from the inside out. This will result in the water evaporating out of the coating at a rapid rate, initiating the cross-linking process earlier. This will ultimately mean you can handle the product quicker, and the coating will become harder, sooner. In combination with the right air movement and temperature, investing in infrared drying unit is the most suitable solution.

Humidity control

Humidity control is essential with waterborne paint. Unlike solvent-based paint, waterborne does not dry well on its own. A humidity level between 40%-50% is perfect. If the humidity level is too high, then the paint will dry slower. If the humidity is very low then this could cause orange peel effect in the surface. Industrial humidifiers for the joinery industry are available online. Or ask our representative for the right address.

The transition to waterborne paint will take a week till maximum two weeks to implement in your production facility. Our technical sales representatives will take you by the hand to make sure the transition goes smoothly.

We will also help you with setting up the recycling and disposal of waste water. Less waste is typically created compared to solvent-based paint. Additionally, less product is needed to cover the same area, waterborne paint color matches better and it usually lasts longer in sealed containers, which helps with inventory control.

Waterborne paint is significantly less dangerous for employees

Waterborne paint promotes a healthier and safer work environment for your employees, compared to solvent-based coatings. It means fewer hazards and a workplace free of any potential injuries or problems.

Of course we continue to strongly recommend to use good protection equipment for your employees. Compared with solvent-based paints, waterborne paints do not require thinners and other additives.

The main difference between water and solvent is in how the two evaporate. The key with waterborne coatings is humidity, temperature and air flow, while the evaporation of solvent-based coatings is driven by temperature only.

The reason for this is that as the water evaporates from the paint surface, the air molecules near the surface become saturated and can’t hold more water, slowing down the process. If air is kept moving across the surface, the saturated air is constantly being replaced with non-saturated air.

Transport

Waterborne wood coatings are classified as NON-ADR. This means that the products are very easy to ship from point A to point B. With solvent-based products this is more difficult and expensive.

The future

Binder and polymer manufacturers are also investing nowadays in sustainable and waterborne innovations. This means that waterborne solutions will become even more sustainable in the future. More and more coatings will contain polymers that are being made from non-fossil fuels and will have a carbon friendly structure, causing less emissions.

Fact: solvent-based coatings will become less and less important over time.