Watch a video of the Three Layer Wet Paint System
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1) CO2 emissions have been significantly reduced with this newly developed coating system. It combines the primer coating process with that of the base and clear top coats. All three layers are applied in succession and then baked to a fine finish.
2) By efficient extremely precise paint control technology and combining it with a highly efficient robotic coating system, Mazda has achieved uniform coating thickness and raised the efficiency of its painting line. Further, in collaboration with a paint company, Mazda has developed a new low-solvent paint that allows the three layers to be applied in succession. These advances reduce volatile organic compound (VOC) emissions and overall costs while improving the finished quality.
(1) Use of low-solvent paint
Simply reducing the amount of solvent used in paint will increase the paint viscosity and make it unsuitable for coating. To prevent this, Mazda reduced the molecular weight of the coating resin and thereby the paint viscosity. By developing this low-solvent paint, Mazda has significantly reduced VOC emissions.
(2) Preventing the mixing of the primer and base coat
When the primer and base coat mix, it leads to a degradation of glossiness and color. To prevent this, we developed a new resin called an interface control polymer, and added it to the primer paint. When the primer is applied, the interface control polymer creates a barrier layer on the paint surface.
Though uniformly dispersed throughout the primer when it is applied, the larger molecules of the interface control resin are soon drawn to the surface of the thin layer of paint by surface tension, where they form a highly viscous barrier layer at the interface between the primer and base coat. This technology prevents color degradation and ensures the finished quality is as good as or better than conventional coating methods.
(3) Improvement of coating efficiency
To eliminate the unnecessary application of paint to areas that do not need to be coated, and to obtain a uniform coating thickness with a minimum amount of paint and energy, the Three Layer Wet Paint System employs robotics instead of the conventional reciprocal automated painting method. The advantages of robotic painting are that paint can be sprayed from the ideal angle for any surface, it offers excellent repeatability, and a set distance can be accurately maintained between the nozzle and target surface, even when the surface is curved.
1) Reduced energy consumption
By combining the primer and top coat processes, the separate primer booth and primer drying furnace have been eliminated. As a result, total energy consumption in the paint shop has been reduced by 15 percent.
2) Reduced VOC emissions
The decrease in the volume of paint used and the development of Mazda's low-solvent paint have lowered VOC emissions by approximately 45 percent compared to the conventional painting process. As a result, Mazda is able to meet the European VOC regulations of 35 g/m2 without having to redesign its paint line for a switch to water-based paint.