Upotuspäällystys

Upotuspäällystys, also known as immersion coating or dip coating, is a surface finishing process where an object is submerged into a liquid coating material and then withdrawn. The viscosity of the coating, the withdrawal speed, and the object's geometry all influence the thickness and uniformity of the resulting layer. This method is often used for applying paints, varnishes, adhesives, waxes, and protective films.

The process can be performed manually or automated. In automated systems, the object is typically lowered into a bath containing the coating and then slowly raised, allowing excess material to drain back into the bath. The rate of withdrawal is crucial for controlling the final film thickness. Slower withdrawal generally leads to a thicker coating.

Upotuspäällystys is valued for its simplicity and its ability to coat complex shapes and internal surfaces. It is a cost-effective method for mass production and can achieve uniform coatings, especially when applied to simple geometries. However, challenges can arise with achieving very precise thickness control, potential for drips and runs, and the need to manage waste material from the coating bath. Different types of immersion coating exist, including electrocoating (electrophoretic deposition), where an electric current is used to deposit the coating material. This technique is widely used in industries such as automotive, appliance manufacturing, and metal finishing due to its efficiency and ability to provide corrosion resistance.