Car Painting

What are the top painting technologies commonly used in the automobile industry?

The paint on your vehicle determines its first impression.The automobile industry uses a variety of painting technologies to apply coatings to vehicles. The gloss, colour, volume of the body, etc. are all factors that help figure out what technology is chosen for painting. Some of the most common technologies that are used in painting automobiles include:

1. Electrostatic spraying:

In this method of painting, the paint particles are positively charged from the paint gun and the vehicle body is grounded or negatively charged. This technology uses the electrostatic effect to attract paint particles to the surface of the vehicle, resulting in an even and efficient coating. The positively charged paint particles repel each other creating an even and fine layer of paint. Once the surface is sufficiently coated the negative charge of the surface weakens and paint particles move towards the uncoated sides. Compared to conventional methods of spraying, electrostatic spraying has higher efficiency and lower production time. It is more useful in reaching corners and crevices. Also, it is more beneficial in painting tubular parts. 

2. Powder coating:

This technology uses a dry powder paint made of a thermosetting or thermoplastic polymer that is applied electrostatically to the surface of the vehicle and then cured under heat to create a thick well-defined coat. This results in a hard and durable finish that is resistant to chipping, cracking, and fading. It does not need a solvent and hence no VOCs (Volatile Organic Compounds) are released into the atmosphere. It averts problems like running and sagging, allowing a tougher finish than the conventional paint. The curing time is relatively faster than liquid paints, especially when using UV-cured powder castings.

3. Robot-assisted painting:

This technology uses robots to apply paint to vehicles, resulting in a more consistent and efficient coating. Various companies worldwide are manufacturing industrial robotic painting systems. They provide detailed surface painting and are predominantly used for painting interiors. Also, otherwise unreachable corners on the exterior are painted using paint robots. Paint robots facilitate multicolour painting by exactly replicating intricating designs onto the vehicle bodies. It improves sustainability and removes the need for masking materials and ventilation. Also, time and cost savings are considerably high compared to conventional paint jobs.

4. Waterborne painting:

This technology uses water-based paint, which is less toxic and more environmentally friendly than traditional solvent-based paint. It doesn’t release many VOCs or HAPs (Hazardous Air Pollutants) and contains fewer toxins. It is less flammable and hazardous allowing a safer and eco-friendly work environment for the workers. Using waterborne paints is economically attractive because it cuts the cost of additives and thinners. It also lasts longer and the leftovers can be stored for a longer time compared to solvent-based paints. Waterborne paints provide a glossy finish and protect the vehicle against corrosion while providing a durable coat.

5. Spray painting:

This technology uses compressed air to atomize paint and apply it to the surface of the vehicle. It typically involves using a spray gun to apply paint in a fine mist, which is then dried and cured to create a smooth and even finish. The process may include prepping the car's surface by sanding and cleaning it, masking off areas that should not be painted, and applying a primer before the final paint coat. This method usually uses conventional solvent-based paints that are insensitive to the coat under them and is more durable. It is not affected by the humidity and can cover the irregularities underneath quicker compared to water-based paints. It contains a considerable amount of toxins and can release various VOCs and HAPs.

6. Cathodic electrodeposition (CED):

This technology uses an electrochemical process to deposit paint on the surface of the vehicle. The charged particles from the paint emulsion are deposited on the electrode when a potential difference is created. It is often used as a primer coat in the automobile industry. It provides a corrosion-resistant paint job with good adhesion and uniform coat thickness. It is suitable for painting hollow parts that may be big or small and parts with complex geometry. It is an economical painting method that can be used along with a waterborne, powder or solvent-based top coat.

7. UV-cured painting:

This technology uses ultraviolet light to cure the paint, resulting in a hard, durable finish that is resistant to chipping, cracking, and fading. UV-curing dries the paint quicker, hence improving productivity. It is a cost-efficient method that saves time and improves production time. UV-cured painting gives high quality and durable finish. It can be applied to heat-sensitive parts. Headlights, reflective housings, gaskets, wheels, etc. can all be painted using UV-cured paint. 

It’s worth noting that the choice of technology depends on the specific needs of the manufacturer, such as the size and shape of the components, the production volume, and the final finish required. The painting method chosen also determines the cost, downtime and longevity of the paint job.