How Does In-Mold Labeling (IML) Work?

How Does In-Mold Labeling (IML) Work?

To clearly understand how in-mold labeling works, we can break the process into six key production stages:

1. Label Printing

High-resolution labels are printed using flexographic, gravure, or offset printing technologies. Common substrates include:

• Polypropylene (PP)

• Polystyrene (PS)

• Paper/polymer composites

2. Label Cutting & Stacking

After printing, labels are die-cut and precisely stacked into magazine holders, ready for automated placement.

3. Robotic Placement

A robotic arm or static placement system inserts the label into the mold cavity. Precise positioning is essential to avoid wrinkles or misalignment.

4. Mold Clamping

The mold closes and is tightly clamped to secure the label before plastic injection or blowing begins.

5. Injection or Blow Molding

Molten plastic is injected or blown into the mold. Under high heat and pressure, the label bonds with the container wall to form a single integrated product.

6. Cooling & Ejection

The part is cooled and ejected from the mold with the label already embedded—no secondary labeling equipment or post-processing required.