Low Pressure Molding (LPM) with polyamide and polyolefin (hot-melt) materials is a process typically used to encapsulate and environmentally protect electronic components. The purpose is to protect electronics against moisture, dust dirt and vibration.

The process was initially invented by Henkel Corporation in Europe in the 1970s where experiments with hot-melts were used to seal connectors and create strain reliefs for wires. The first commercial use of the Low Pressure Molding process was in the automotive industry. The driving force was to replace toxic and cumbersome potting processes, shorten cycle time, lighter parts and environmentally protect components.

Low pressure molding technology can be applied to wide range of industries and any unique product that needs to be sealed and protected against the environment such as PCB, automotive electronics, automotive wire, connector, sensor, micro switch etc.

LPM technology benefits mainly reveal in two aspects:

1.Product Performance：

LPM can over-mold extensively products and enhance product performance. Product using LPM technology can achieve below benefits:

● Environmentally friendly (RoHS).

● Water-proof.

● Mechanical protection from impact.

● Resistance to temperature (UL94 V-0).

● Resistance to Chemical.

Production:

● Simplify the process, enhance productivity.

● Shorten the development cycle, reduce the R&D cost.

● Save production space.

● No hazardous materials during production.

● SThermoplastic no cure time and increased reliability.

● Molds design flexibility.

The process between LPM and epoxy potting.

LPMS selects high performance hot-melt adhesive, which has excellent mobility. The adhesive takes very small pressure to make it flow to mold, therefore, the products successfully over-molded without causing any harm in the process, greatly reducing the defect product.

Low Pressure Molding applications in automotive electronic products mainly include automotive wiring harness, sensors, on-site casting grommet, waterproof connector, micro-switches, ECU (internal PCB) and so on.

Automotive applications is generally regarded as one of the most difficult area, automotive electronic products must be able to cope with very harsh environments. Before leaving the factory, products need to go through a serial rigorous testing, including high and low temperature storage, constant heat, thermal shock, splashing mud, salt water spray, vibration and electromagnetic interference etc.

In conclusion, high performance hot-melt adhesives can meet the needs of the automotive electronics products to deal with the harsh environment, using Low pressure Molding technology can provide resistance to high temperature, moisture, water, pollution, insulation and so on, protecting the operation of sensor. At the same time increase productivity and reduce the total cost can help automotive electronics manufacturers to enhance the competitiveness of enterprises as well.

Best example : car charger controller

LPMS provides our customers with full technical support services from evaluating products, mold DFM, resin and system selecting, parameters setting to large-scale production.