20/06/2026
In Low Pressure Molding, bubbles inside the molded part are a common defect — but they do not always come from one single cause.
Bubble formation can be related to the material, the mold design, the machine condition, or the process parameters.
1. Material Issues
Hot melt adhesives, especially polyamide-based materials, can absorb moisture if they are not stored properly. During heating, trapped moisture or volatile substances may turn into gas and create bubbles inside the molded part. Contaminated materials or excessive recycled content can also increase the risk of bubble formation.
2. Mold Design Issues
If the mold does not have proper venting, gas cannot escape during the filling process. Poor gate location or complex part geometry can also trap air inside the mold cavity, causing visible bubbles or voids in the final product.
3. Machine & Process Parameter Issues
Incorrect injection speed, pressure, holding time, mold temperature, or poor machine sealing can all affect material flow and gas release. When the process is not optimized, air may remain trapped inside the encapsulated area.
To reduce bubbles, manufacturers need to look at the full system — not just one factor.
At Gluditec, we provide a complete Low Pressure Molding solution, including:
- Mold design support
- Process parameter setup
- Material selection
- Equipment recommendation
- Application testing and optimization
- Technical support for production improvement
Whether you are developing a new application or improving an existing molding process, Gluditec can help you build a more stable, efficient, and reliable Low Pressure Molding solution.
Need support with Low Pressure Molding? Contact Gluditec today and let our team help you optimize your process from material to machine.