How to Use an Adhesion Promoter on Plastic

Using an adhesion promoter is crucial for ensuring paint or coatings stick effectively to plastic surfaces. This specialized product creates a bonding layer that allows subsequent finishes to adhere properly, preventing peeling or flaking.

Here's a simple guide on how to apply adhesion promoter to plastic, focusing on the application and drying steps.

Why Use an Adhesion Promoter?

Plastic surfaces are often smooth and non-porous, making it difficult for paint to adhere directly. Adhesion promoters chemically or physically alter the surface slightly, creating a better grip for the topcoat.

Step-by-Step Application Guide

Applying adhesion promoter correctly involves careful preparation and following specific instructions for the product.

1. Surface Preparation

Before applying any product, the plastic surface must be clean.

• Clean the plastic thoroughly with a suitable cleaner designed for plastic or a mild soap and water solution.
• Ensure the surface is completely dry.
• Remove any grease, oil, dirt, or mold release agents.

2. Applying the Adhesion Promoter

The reference highlights a specific method for application:

• Apply one medium wet coat. Ensure even coverage across the entire area you intend to paint. Avoid applying too thick a coat, as this can lead to runs or an uneven finish.

3. Flashing Time

This is a critical step where solvents in the promoter evaporate. The reference states:

• Plastic Adhesion Promoter must be completely flashed before application of top coat.

• Allow to flash 3 – 5 minutes before topcoating.

• What does "flashed" mean? Flashing refers to the period where the quick-drying solvents in the promoter evaporate into the air. The surface will typically appear less wet or glossy and may feel slightly tacky.

• It's essential that the promoter is "completely flashed" as specified, meaning the solvent evaporation is sufficient for the next layer to bond correctly. The 3-5 minute timeframe is a general guideline for this process.

4. Topcoating

Once the adhesion promoter has properly flashed according to the specified time (e.g., 3-5 minutes) and appears completely flashed, you can apply your chosen topcoat (paint, primer, etc.) over the promoted surface. Applying the topcoat within the recommended window after flashing is often important for optimal adhesion.

Summary Table: Key Steps & Timing

By following these steps, particularly focusing on the application of a single medium wet coat and allowing the product to flash for the recommended 3-5 minutes before applying the topcoat, you can achieve proper adhesion on plastic surfaces. Always consult the specific product's label for detailed instructions and safety information.