How do you coat a screen with emulsion?Updated 6 hours ago

When you're coating screens, the first step is to make sure you're working in a light-safe area. Once you're ready, follow these steps:

1. Degrease the screen.
2. Dry the screen completely. Make sure there is no moisture left on the mesh before applying emulsion.
3. Select your emulsion and prepare it if needed. Some emulsions may require mixing or other preparation before use, so follow the manufacturer's instructions.

4. Select the appropriate scoop coater. As a general rule, use a scoop coater that is about 2-4" shorter than the inside dimension of your screen frame. This gives you enough room to coat the mesh without the scoop coater hitting the frame rails.

   Pro tip: If your scoop coater is a little too wide to use comfortably in one direction, you can rotate the screen 90° and coat it from the other direction.

5. Pour the emulsion into the scoop coater. Add enough emulsion to cover the bottom of the scoop coater and create a small reservoir. You don't need to completely fill the coater.
6. Hold the screen vertically with your non-dominant hand, or carefully lean it against a wall or other stable surface. Start with the print side of the screen facing you.
7. Pick up the filled scoop coater with your other hand and place the edge of the coater against the mesh about 1" above the bottom of the frame.
8. Tilt the scoop coater toward the mesh until the emulsion makes contact with the screen across the entire length of the coater. Then, using even pressure, smoothly pull the scoop coater up the mesh. Keep the speed and pressure as consistent as possible and stop about 1" before reaching the top of the frame.
9. Tilt the scoop coater back away from the mesh while keeping the edge in contact with the screen. This allows any excess emulsion to flow back into the reservoir of the scoop coater instead of remaining on the mesh.
10. Remove the scoop coater and turn the screen around so the squeegee side is facing you.
11. Inspect the emulsion coating. If you have excess emulsion or an uneven area, you can use the edge of the scoop coater to gently even out the coating. Avoid repeatedly scraping the mesh, as this can create an inconsistent coating.
12. Repeat the coating process on the squeegee side. Apply the emulsion evenly across the mesh, maintaining consistent pressure and speed.

How Many Coats Should You Apply?

The number of coats you apply depends on your mesh count, emulsion, design, ink, and the amount of ink deposit you're trying to achieve. Your goal is to create the appropriate emulsion-over-mesh (EOM) for the job.

For example, fine-detail or poster printing may require a thinner, more controlled stencil, while certain textile printing applications may benefit from a thicker stencil to achieve a heavier ink deposit.

Once your screen is coated, place it in a dark, clean, and controlled drying area with the squeegee side facing up and allow the emulsion to dry completely before exposing it.

To learn more about coating screens, read this blog.