Precision in medical sealing: mini injection molding of LSR in an advanced skin closure system
In 2021, ENBI Plastics & Silicones was approached by a medical client to develop two silicone components for an advanced skin closure system. Designed to promote faster and more hygienic wound healing, the system combines medical-grade adhesion with the flexibility and durability of liquid silicone rubber (LSR).
The project offered an opportunity to deepen ENBI’s expertise in mini injection molding of LSR. With the implementation of a new, fully electric production line and the required medical certifications, the team dedicated itself to developing a solution that meets the most stringent standards of the medical industry.
From feasibility to validation
To successfully industrialize the product, ENBI applied its proven workflow. During the pre-engineering phase, product specifications were translated into concrete technical requirements, focusing on material selection, molding technology, and concept validation. ENBI’s engineering team explored how injection molding could be optimized for extremely small shot weights and tested various process methods to ensure consistent quality and stability.
A unique production challenge
The development presented several technical challenges. One of the most critical aspects was the design of the applicator tip, which comes into direct contact with the skin. To guarantee both functionality and aesthetics, no flash formation could occur during the molding process - a requirement that pushed the limits of mini injection molding precision.
Air-tightness was equally crucial to ensure a uniform distribution of the adhesive. To achieve this, an ultra-small silicone sealing ring was developed with a shot weight of <0.1 grams per injection. This miniature component required maximum control over material behavior, shot volume, and cycle time - a challenge that was successfully translated into a stable and repeatable process.
Production under medical conditions
All production took place in a controlled medical environment in compliance with ISO 13485. Every step - from material handling to final inspection - was carried out under a strict quality framework, supported by validated process documentation and continuous monitoring to ensure repeatability and traceability.
An innovative step forward
By combining technical expertise, process control, and close collaboration, ENBI delivered a high-precision medical solution that contributes to faster and safer wound healing.
The project not only demonstrates the power of co-engineering and mini injection molding, but also reflects ENBI’s commitment to precision, quality, and continuous innovation in medical manufacturing.
Unseen, yet essential!
