Factory Paint Finish Information - Factory Paint Finish Application Process
1. Factory Paint Finish Application Process
There are many requirements for body coating such as external finish (appearance), durability, corrosion resistance and others, as it has a significant impact on quality and marketability of the vehicle. Mass production vehicles go through a multi-layered painting process, including chemical conversion coating and basecoating for corrosion resistance and improved durability. The middle and topcoats provide a high quality external finish. There are also many more paint processes require to produce high quality automobile bodies and parts.
1.
Chemical Conversion Coating Process:
The vehicle body is fully immersed (dipped) into acrylic washer fluid to remove oil and contaminants. This also form a crystalized film of zinc phosphate similar to the dip method.
2.
Basecoat Process:
The vehicle body is fully immersed (dipped) and electrodeposition (ED) coating is applied. Primer or paint coats the entire part without missing any areas, which improves anti-corrosion durability. ED coating uses epoxy group resin paint.
3.
Sealing Process:
Seals fitted parts of the body after welding and in joint areas such as hemmed parts like doors force-fed sealer gun. Body sealer helps prevent dust and water entry and also improves corrosion resistance.
4.
Undercoating Process:
PVC (polyvinyl chloride) is applied to the lower body, including the front and rear wheel houses. Helps prevent paint and body damage from rock chips and other causes. Also contributes to sound, heat, and vibration control.
5.
Hard Chip Guard Coating Process:
Chip guard primer is applied to side sill surface. It helps prevent paint film damage to side sill caused by rock chips, etc.
6.
Soft Chip Guard Coating Process (only for high corrosion areas):
Soft chip guard primer is applied to the edges of hood, roof and doors etc. It helps preventing paint film damage and rust cause by rock chips.
7.
Intermediate Coating Process:
Maintains paint film thickness and improves clarity and corrosion resistance of the total body paint film, including the topcoats. Bell type coating conveyor lines maintain film thickness consistency.
8.
Intermediate Coat Sanding Process:
Intermediate coating paint film is sanded in order to improve the smoothness of the film surface and adhesion of the topcoats.
9.
Topcoating Process:
Enamel paint is applied to inside and outside of body using robotic painting equipment. For metallic and pearl paint, a clearcoat is applied after the enamel paint. A high quality baked acrylic type paint or waterborne paint is used to improve corrosion resistance and appearance.
10.
Paint Inspection Process:
Paint quality is inspected to judge OK/NG based on the inspection criteria. Coating condition, film thickness, film hardness, adhesion, etc. are thoroughly checked by visual and mechanical means.
11.
Two-Tone Paint Process (Special Paint):
(Example) Two-tone paint may be applied after topcoating depending on specifications.
12.
Internal Rust Proofing Process:
A special zinc-based rust proof paint or wax is applied to the critical areas that requires rustproofing treatment using spray guns in order to further enhance anti-corrosion performance.
13.
Complete Build Unit Rust Proof Process:
Inside and outside rustproofing. The wax coating is even applied inside the tail gate, doors, and to the underbody for anti-corrosion performance enhancement.