Custom FPC Silicone Overmolded Waterproof Seal
Item specifics
- Material
- Liquid Silicone Rubber
- Process
- FPC Silicone Overmolding / LSR Injection Molding
- Application
- Wearable Electronics / Sensors / Flexible Circuits
- Function
- Waterproof / Dustproof / Circuit Protection
- Structure
- Silicone Encapsulation / Bonding Edge / Sealing Area
- Service
- OEM / ODM Custom Manufacturing
Review
Description
Custom FPC Silicone Overmolded Waterproof Seal
SiliconePlus manufactures custom FPC silicone overmolded waterproof seals for flexible circuits, wearable sensors, smart electronics, medical electronic modules, automotive electronic parts and compact waterproof devices.
This product is not a standard silicone gasket. It is a precision silicone over FPC component. Liquid silicone rubber is molded onto selected areas of the flexible printed circuit to provide sealing, insulation, strain relief and environmental protection.

Designed for Flexible Circuit Protection
FPC components are thin, flexible and sensitive to positioning accuracy. During silicone overmolding, the FPC must be placed accurately inside the mold so that the silicone layer covers the required protection area without damaging pads, traces, terminals or connection zones.
A well-designed FPC silicone overmolded part can help protect the circuit from water, dust, moisture, vibration, bending stress and daily handling damage.
Key Structure Design
The overmolded silicone area can be customized according to your FPC layout, assembly position and sealing requirements.
Typical structure options include:
- Silicone encapsulation area
- Exposed FPC terminal area
- Bonding edge
- Waterproof sealing zone
- Strain relief section
- Flexible bending area
- Positioning hole clearance
- Sensor protection area
- Connector transition protection
- Thin-wall silicone coating area
Key Advantages
- Integrated silicone over FPC structure
- Waterproof and dustproof protection
- Better circuit protection during assembly
- Flexible strain relief design
- Stable silicone positioning accuracy
- Custom sealing path and protection area
- Suitable for compact electronic modules
- Reduced manual sealing or adhesive process
- OEM/ODM customization from drawings or samples
Application Areas
This custom FPC silicone overmolded seal can be used for:
- Wearable sensors
- Smartwatch internal modules
- Medical electronic modules
- Waterproof electronic connectors
- Automotive electronic modules
- Flexible circuit protection parts
- Smart device internal components
- Sensor sealing components
- Portable electronics
- Compact waterproof electronic assemblies
Custom Manufacturing Options
SiliconePlus can customize the silicone overmolding structure according to your FPC design, waterproof target, assembly method and product use environment.
Available options include:
- Custom silicone coverage area
- Custom silicone hardness
- Custom silicone thickness
- Custom sealing edge design
- Custom exposed terminal area
- Transparent, black, gray or custom colors
- FPC positioning fixture design
- LSR injection molding
- Insert molding
- Prototype sampling and mass production

Engineering Considerations Before Mold Opening
FPC silicone overmolding requires careful evaluation before tooling. Small dimensional errors may affect circuit function, assembly stability or waterproof performance.
Before starting a project, we recommend confirming:
- FPC material and thickness
- Copper trace and pad position
- Exposed terminal area
- Silicone coverage boundary
- Silicone hardness requirement
- Waterproof target
- Bending and strain relief area
- Assembly space
- Testing standard
- Estimated production quantity
Quality Control for FPC Overmolding
For FPC silicone overmolding projects, quality control should focus on silicone position accuracy, bonding edge, flash control, exposed pad protection, thickness consistency and visual appearance.
SiliconePlus can support dimensional inspection, visual inspection, assembly check, waterproof test support and CCD inspection according to project requirements.
Why Choose SiliconePlus?
SiliconePlus focuses on custom silicone overmolding, liquid silicone rubber injection molding and precision silicone parts manufacturing. We support silicone over plastic, silicone over metal, silicone over FPC and waterproof integrated silicone components.
For FPC silicone overmolding projects, our engineering team can help review positioning accuracy, mold feasibility, silicone coverage design, bonding structure, demolding risk and mass production stability.
Send Your FPC Overmolding Project
If you need a custom FPC silicone overmolded seal, waterproof flexible circuit protection part or silicone over FPC electronic component, please send us your 2D drawings, 3D files, FPC samples, product photos and technical requirements.
Our team will evaluate your project and provide a custom LSR overmolding solution.
Specifications
| Item | Specification |
|---|---|
| Product Name | Custom FPC Silicone Overmolded Waterproof Seal |
| Material | Liquid Silicone Rubber |
| Process | FPC Silicone Overmolding / LSR Injection Molding |
| Application | FPC Circuit, Wearable Sensor, Electronic Module, Waterproof Connector |
| Function | Waterproof, Dustproof, Insulation, Strain Relief, Circuit Protection |
| Structure | Silicone Encapsulation, Bonding Edge, Sealing Area, Exposed Terminal |
| Substrate | Flexible Printed Circuit / FPC |
| Color | Transparent, Black, Gray or Custom Colors |
| Hardness | Customized According to Project |
| Waterproof Rating | IP67/IP68 Design Support |
| Service | OEM/ODM Custom Manufacturing |
| Input Required | 2D Drawing, 3D File, FPC Sample, Product Photo, Technical Requirements |
| Quality Control | Positioning Inspection, Visual Inspection, Dimensional Check, CCD Inspection Support |
FAQ
1. What is FPC silicone overmolding?
FPC silicone overmolding is a custom process that molds silicone rubber onto selected areas of a flexible printed circuit. It helps provide waterproof protection, dustproof sealing, insulation, strain relief and mechanical protection.
2. Can you customize the silicone coverage area?
Yes. We can customize the silicone coverage area according to your FPC layout, exposed terminal position, waterproof target, assembly method and product structure.
3. Will the silicone cover the electronic pads or terminals?
Only the required areas will be covered. Exposed pads, terminals, contacts and connection areas should be clearly marked in the drawing before mold design.
4. Can this product support IP67 or IP68 waterproof design?
We can support IP67/IP68 waterproof design according to your complete product structure. Final waterproof performance should be verified through testing on the finished assembly.
5. What information do you need for quotation?
Please provide 2D drawings, 3D files, FPC samples, material requirements, silicone coverage area, waterproof target, hardness, color, quantity and testing requirements.
6. Can you help check the design before mold opening?
Yes. Our engineering team can review the FPC positioning method, silicone coverage boundary, bonding edge, demolding risk, flash control and mass production feasibility before tooling.













