Smartwatches, health monitoring patches, flexible sensors… wearable devices are evolving from "electronic products" into "electronic skin." These devices attach to the human body for extended periods, imposing special requirements on material safety, flexibility, and durability. Liquid silicone rubber (LSR), thanks to its good biocompatibility, soft skin-friendly feel, and excellent breathability, is becoming a material of significant interest in the wearable and flexible electronics sectors.

The core material requirements for wearable devices are: biocompatibility, softness and breathability, resistance to sweat corrosion, and comfort during long-term wear. LSR inherently offers good biocompatibility, with certain grades having passed relevant biocompatibility tests, making them suitable for prolonged contact with human skin. At the same time, its soft elastomeric properties allow it to maintain integrity under bending and stretching, resisting cracking or detachment.

In terms of application scenarios, LSR is finding expanding uses in the wearable field: first, as a coating for flexible printed circuit boards, providing moisture and sweat protection without compromising sensor sensitivity; second, for sealing and bonding health monitoring patches, ensuring stable electrode-to-skin contact; and third, for edge sealing of flexible displays, balancing protection with aesthetics.

Looking at industry trends, as health monitoring shifts from "occasional measurement" to "continuous monitoring," the demands on material comfort and stability during long-term wear will continue to increase. If LSR can further optimize its breathability and conductive compatibility, it is expected to play an even more important role in next-generation flexible electronic products.

When selecting materials, key parameters to focus on include: biocompatibility rating, Shore hardness (lower hardness is typically chosen to enhance wearing comfort), and resistance to sweat and UV exposure. For wearable device R&D teams, LSR represents a pragmatic material choice for flexible electronics solutions.

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