Coating Methods Of Parts With Polymers

You can see lots of examples around you and in daily life that parts are coated with polymers. Coating processes are very important in the polymer industry. There are various methods for coating different parts in different shapes. Here, you can find the summary information about the general coating processes with polymers.

In general, there are three types of polymer coating methods are used in the industry.

  • Coating processes of three-dimensional shapes which is the most common one.
  • Coating of wires and cables.
  • And the coating of planar surfaces.

How The Three Dimensional Parts Are Coated?

The logic of coating three-dimensional shapes is very straightforward. Dipping and spraying are the most used types of coating processes for three-dimensional parts.

In the dipping process, the three-dimensional object is dipped inside polymer melt or also called a polymer bath. In the spraying process, the melted polymer is sprayed onto three-dimensional parts.

How The Wires And Cables Are Coated?

Coating of wires and cables is a special type of plastic extrusion process. In the most basic explanation, the polymer melt is supplied from a special screw mechanism or pump through a spinneret hole, and the bare wires are also supplied through these spinnerets. Coated wires or cables are drawn and wound on bobbins. You can find detailed information about the coating of wires and cables at the above link.

What Are The Types Of Planar Surface Coating Methods?

In general, two types of planar surface coating methods are used; the doctor blade method and the roll method. In two types of planar surface coating methods, the coating polymer is supplied by the slit die extrusion method or calendering method. Because thin sheets and films of plastic materials are required for coating operations.

Explanation of two planar surface polymer coating methods
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In the doctor blade method, the material to be coated is supplied by rolls, and polymer melt is supplied onto this material. With the help of pair of blades and a roller, the material to be coated is coated with a polymer melt. The thickness of the coating is adjusted with the placement of the blade.

If a roll is used in the coating mechanism, instead of a blade, this method is called as roll method.

In planar coating methods, special planar parts such as cardboard and thin metal parts are coated with polymers such as nylon, PVC, polyester, and most commonly, polypropylene and polyethylene. The thickness of planar surface coating methods is generally between 0.01 to 0.10-millimeter thickness.


As you understand that the classification of polymer coating methods is made according to the parts that to be coated with these methods. There are lots of kinds of sub-methods available for each class of coating applications.

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