Liquid Silicone Rubber (LSR) Injection Molded Parts
Liquid Silicone Rubber (LSR) injection molding. Fully automated process for high-precision parts, microcomponents, and medical products. Hardness 20-90 Shore A. Compliance with FDA, EC 1935/2004, USP VI, ISO 10993, ISO 13485, EN 45545-2, and UL94.
Process Principle
LSR injection molding uses two-component liquid silicone compounds (A/B) that are automatically mixed and injected into closed molds at high pressure. This process guarantees repeatability, purity, and micrometric tolerances, ideal for medical, optical, and electrical components.
Materials and Formulations
Uses LSR (Liquid Silicone Rubber) silicones with hardnesses from 20 to 90 Shore A. Available formulations: medical-grade, food-grade, fire-retardant, optical-grade, antistatic, and self-lubricating. 100% platinum-cured, byproduct-free, with compliance to FDA, EC 1935/2004, USP VI, ISO 10993, and EN 45545-2.
Dimensions and Finishes
Enables the manufacture of microcomponents, complex parts, and very precise geometries with ISO 3302-1 M1 tolerances. Smooth, optical, or matte finishes according to drawing. Possibility of translucent, pigmented colors, or optical LSR for photonic applications.
Production Environments
Manufacturing in a validated ISO 8 cleanroom, specially designed for medical, pharmaceutical, and optical devices. Processes certified under ISO 9001 and ISO 13485, with control of mixing, temperature, dosing, and complete traceability of each batch.
Product Gallery
Key Technical Data
Typical values obtained according to series datasheets (17, 30) and indicated standards. May vary based on hardness, formulation, and application. Final validation is the customer's responsibility.
| Property | Typical Values | Standard |
|---|---|---|
| Hardness (Shore A) | 20 – 70 (núcleo habitual: 40–60) | ISO 7619-1 |
| Tensile Strength | 7 – 11 MPa | ISO 37 |
| Elongation at Break | 400 – 1200 % | ISO 37 |
| Tear Resistance (Type C) | 17 – 47 kN/m | ISO 34-1 |
| Density | 1,11 – 1,20 g/cm³ | ISO 2781 |
| Working Temperature | –60…+200 °C (up to +215 °C in some formulations) | — |
| Tolerances | Molding Class M2 (LSR Injection) | ISO 3302-1 |
| Sectoral (On Request) | FDA / CE 1935/2004 / USP VI / ISO 10993 / RoHS / REACH | — |
Certifications and Regulatory Compliance in Silicone Molding
Every molding batch is manufactured under strict validation protocols, guaranteeing conformity with international standards and integral traceability of the material and the mold.
Main Certifications
- ISO 9001:2015 – Quality Management System
- ISO 13485:2016 – Medical Devices
- EN 9100 – Aerospace and Defense
- GMP – Good Manufacturing Practices
- ISO 10993 – Medical Biocompatibility
- USP Class VI – Pharmaceutical Biocompatibility
Regulatory Compliance
- FDA 21 CFR 177.2600 – Food Contact
- EC 1935/2004 – Materials in Contact with Food
- EN 45545-2 – Railway Fire Protection
- UL94 – Material Flammability
- ISO 10993 and USP Class VI – Medical and Pharmaceutical Biocompatibility
- REACH (1907/2006) and RoHS (2015/863) – Chemical and Electrical Substances
Main Application Sectors
Key Applications
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Medical and implantable microcomponents
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Precision seals and valves
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Optical parts and electronic encapsulation
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Membranes, buttons, and tactile parts
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Automated high-volume production
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Stoppers and membranes for microfluidics and laboratory chips
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Seals for fuel injectors (High Precision)
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Lens and light-guide components for LED lighting (Optical LSR)
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Flow control valves for drinking water systems
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Miniature gaskets for hearing aids and consumer electronics devices
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Flexible housings for integrated sensors in wearables
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Contact tips and insulators in fibre optic connectors
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Pressure equalisation membranes in aviation equipment
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Pumping and dosing chambers in professional coffee machines
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Components for catheters and diagnostic probes (Biocompatibility)
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Seals for small-diameter pipeline inspection chamber closures
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Plasma-sterilisation resistant buttons and covers
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Small-diameter O-rings for pneumatic fittings
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Cushioning discs for precision stepper motors
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Respiratory mask and portable ventilator components
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Connectors for electric vehicle batteries (Fire-retardant/High Temp)
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Microelectronics encapsulation in hostile environments
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Parts for high-purity ink and chemical dosing
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Valves and stoppers for surgical instrument cleaning systems
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Membranes for medical gas pressure regulators
Manufacturing and Delivery Options
- Geometries: Micro, thin, or complex three-dimensional
- Volumes: Medium, large, or continuous production
- Materials: Transparent, pigmented, optical, or self-lubricating LSR
- Formulations: Medical-grade, Food-grade, Fire-retardant, Optical, Antistatic
- Production: ISO 8 Cleanroom with total process control
- Delivery: Sterilizable, tested, and traced parts
- Tolerancias: clase M1
Product Selection Matrix
| Customer Requirement | Recommended Solution |
|---|---|
| Prototypes or short runs | Compression Molding |
| High-volume runs with dimensional precision | HCR Injection Molding |
| Medical or optical microcomponents | LSR Injection Molding |
| Integration with metal or plastic | Overmolding |
| Integración multicomponente | Overmolding |
Technical Conclusion and Recommendations
LSR liquid silicone injection molding from ProSilicones64 guarantees micrometric precision, purity, and repeatability in every part.
The medical and food-grade formulations, along with production in an ISO 8 cleanroom and ISO 13485 certification, ensure compliance with the most demanding regulatory requirements on the market.
This process represents the maximum expression of silicone engineering, positioning ProSilicones64 as a European leader in high-precision liquid molding.
La solución para dispositivos médicos de nueva generación.
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