Plastic-silicone overmoulding

Silicone overmoulding on metal and thermoplastic

We manufacture hybrid parts by overmoulding silicone onto metallic or thermoplastic inserts. Bonding is achieved by chemical primer (silane) or by retaining geometry. In Italy (Top Tech Silicones) we run a plastic-silicone 2K two-shot press that injects the plastic insert and the silicone consecutively in the same mould, with no intermediate handling.

InsertsMetal · Engineering thermoplastic
BondingChemical (silane) or mechanical
2K two-shotItaly · ISO 8 cleanroom
CertificationsISO 9001 · ISO 13485 · USP VI · FDA

Compatible with VMQ silicone (HCR) and liquid silicone (LSR), platinum or peroxide cure depending on the application. Sterilisable by autoclave, steam or gamma radiation depending on the formulation.

The product

Prepared insert and silicone injection in the same mould for a permanent chemical or mechanical bond.

The insert is prepared with a chemical primer (functionalised silane) or with retaining geometry (recesses, holes, perforations) that anchors the silicone during vulcanisation. The silicone is injected on top at controlled pressure and temperature. The result is a single part with two materials joined together: structural rigidity from the insert and elastomeric properties from the silicone in the functional area.

Plastic-silicone overmoulded part
Plastic-silicone overmoulded part
Plastic-silicone overmoulded part
Plastic-silicone overmoulded part
Plastic-silicone overmoulded part

Specifications

Process
Overmoulding · prepared insert + injected silicone · chemical or mechanical bonding
Capacity
Italy (Top Tech): 2K two-shot + plastic press · France (Progress): overmoulding in HCR and LSR workshops
Cleanroom
Italy · ISO 8 (ISO 14644-1) · plastic-silicone two-shot press for medical, pharmaceutical and food grades
Metallic inserts
Stainless steel · aluminium · brass · copper
Thermoplastic inserts
PA · PEEK · PPS · PC · PMMA · ABS
Bonding
Chemical (silane primer) · mechanical (retaining geometry) · combined
Silicone compounds
HCR (peroxide or platinum VMQ) · LSR (A/B two-component platinum)
Hardness
10 to 90 Shore A according to the applicable series
Tensile strength
Standard series: 6 to 10 MPa · series 02 from 3.5 MPa in soft grades (ISO 37)
Elongation at break
300 to 700 % · up to 1,000 % in soft formulations (ISO 37)
Tear strength
Standard series: 15 to 30 kN/m · implantable series 17 up to 46.7 kN/m (ISO 34-1)
Density
VMQ series: 1.07 to 1.23 g/cm³ · FVMQ series 13 by design: 1.40 to 1.46 g/cm³ (ISO 2781)
Service temperature
–60 °C to +200 °C continuous · up to +300 °C in heat-resistant series
Tolerances
ISO 3302-1 class M2 · class M1 on critical parts
Management system
ISO 9001:2015 · ISO 13485:2016
Production environments
ISO 8 cleanroom (medical · pharmaceutical · food) · Controlled industrial workshop (rest)
Biocompatibility
USP Class VI · ISO 10993 (medical grade)
Food contact
FDA 21 CFR 177.2600 · CE 1935/2004 · BfR XV (food grade)
Sector-specific
EN 45545-2 railway · UL94 V-0 flame retardant
Sterilisation
Autoclave · steam · gamma radiation · ethylene oxide
Restricted substances
REACH (1907/2006) · RoHS (2015/863)
Typologies

Overmoulding catalogue: encapsulation, sealing on housings and 2K two-shot for devices

Encapsulation and electrical connection

  • 01Sensor encapsulation
  • 02Overmoulded sealed connectors
  • 03Coil and solenoid insulation

Sealing on housings

  • 01Seals on cable glands and bushings
  • 02Sealing rings on flange
  • 03Membranes on plastic body

Devices and 2K two-shot

  • 01Ergonomic grips on instruments
  • 02USP VI 2K medical devices
  • 03Buttons and tactile elements
Materials

Series compatible with overmoulding

Series 12 – Platinum-cure silicone with strong mechanical properties and versatility

Series 12 is a platinum-cured silicone compound processable by extrusion and moulding, recognised for its strong mechanical properties. It offers a very wide hardness range (10 to 90 Shore A) and food-contact compliance. A notable feature is that suction tubes manufactured with the EQ1260T grade are validated for integration into medical devices requiring CE marking.

Platinum-cured silicone with excellent mechanical properties and broad hardness availability. Processable by extrusion and moulding, compatible with food contact and medical applications (depending on formulation).

Shore A hardness20 – 90
Temperature range-60 °C / 200 °C
Peak temperature315 °C
Density (g/cm³)1.11 – 1.20
Tensile strength (MPa)6.0 – 9.0
Elongation at break (%)100 – 1000
Tear strength (kN/m)17.0 – 30.0
Curing systemPlatinum
Processing methodExtrusion and Moulding
Base colourNatural / Transparent
Available coloursRAL colours on request

Applications

  • Tubes (Øint 0.5–145 mm), profiles (cords, square, rectangular), moulded parts and industrial or medical applications.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • BfR IX and XV
  • CE 1935/2004
  • ISO 10993 (depending on formulation)
  • USP Class VI
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 10 – High-tear platinum-cure silicone for medical and food-grade applications

Series 10 is a platinum-catalysed silicone blend designed to deliver exceptionally high tear strength. It can be processed by extrusion and moulding. Platinum curing gives it superior purity (no peroxide by-products), making it ideal for medical applications (USP Class VI, ISO 10993) and food contact, while also ensuring high-performance mechanical properties.

High-purity technical silicone catalysed with platinum, processable by extrusion and moulding. It offers very good tear strength, excellent mechanical properties and food and medical compatibility depending on the formulation. It has a thermal range from -60 °C to +200 °C and is available in a wide range of hardnesses (40–80 ShA).

Shore A hardness40 – 80
Temperature range-60 °C / 200 °C
Density (g/cm³)1.12 – 1.24
Tensile strength (MPa)7.0 – 9.0
Elongation at break (%)320 – 760
Tear strength (kN/m)33.0 – 55.0
Catalysis typePlatinum
Processing methodExtrusion and moulding
Base colourNatural / Transparent
Available coloursRAL colours on request

Applications

  • Inflatable seals, tubes, profiles and moulded parts for industrial, medical and food-contact applications.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • BfR IX and XV
  • CE 1935/2004
  • ISO 10993 (depending on formulation)
  • USP Class VI
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 17 – Platinum-cure short-term implantable silicone (< 29 days)

Series 17 is a platinum-catalysed silicone blend, designed specifically for medical applications requiring short-term implantation (less than 29 days according to NUSIL data). It can be processed by extrusion and moulding. Its high-purity and biocompatible formulation makes it suitable for catheters, drains, tubing with radiopaque lines and other temporary invasive medical devices.

Shore A hardness25 – 80
Temperature range-60 °C / 200 °C
Density (g/cm³)1.11 – 1.20
Tensile strength (MPa)7.9 – 10.8
Elongation at break (%)700 – 1200
Tear strength (kN/m)33.5 – 46.7
Catalysis typePlatinum
Processing methodExtrusion and moulding
Base colourTranslucent

Applications

  • Tubing, tubing with radiopaque lines, profiles, moulded parts and O-rings for medical applications.

Certifications and technical standards

  • USP Class VI
  • ISO 10993 (depending on formulation)
  • RoHS compliant
  • REACH compliant

Series 2 – Peroxide-cure silicone for general and food-grade use

Series 2 is a peroxide-cured silicone compound designed for versatile processing by extrusion and moulding. It stands out for an exceptionally wide hardness range (10 to 90 Shore A) and the option of food-contact compliance depending on the formulation.

Peroxide-cured silicone compound. Provides excellent thermal stability and the option of food-contact or medical-grade use depending on the formulation.

Shore A hardness10 – 90
Temperature range-60 °C / 200 °C
Peak temperature315 °C
Density (g/cm³)1.07 – 1.23
Tensile strength (MPa)3.5 – 9.5
Elongation at break (%)125 – 950
Tear strength (kN/m)10.0 – 23.0
Curing systemPeroxide
Processing methodExtrusion and Moulding
Base colourNatural / Transparent
Available coloursRAL colours on request

Applications

  • Tubes (Øint 0.5–145 mm), profiles (cords, square, rectangular), moulded parts and varied industrial applications.

Certifications and technical standards

  • FDA 21 CFR 177.2600
  • BfR IX and XV
  • CE 1935/2004 (Food contact)
  • ISO 10993 (medical grade depending on formulation)
  • USP Class VI
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 4 – Peroxide-cure silicone with low compression set and oil resistance

Series 4 is a peroxide-cured VMQ silicone formulation developed specifically for applications requiring excellent elastic recovery after compression (low compression set) and good resistance to oil contact.

Silicone with good compression set and oil resistance. Moulding: 40-80 ShA. Extrusion: 40-75 ShA.

Shore A hardness40 – 80
Temperature range-60 °C / 200 °C
Density (g/cm³)1.11 – 1.40
Tensile strength (MPa)6.0 – 7.5
Elongation at break (%)100 – 350
Tear strength (kN/m)10.0 – 15.0
Curing systemPeroxide
Processing methodExtrusion and Moulding
Base colourTranslucent beige / Opaque beige
Available coloursRAL colours on request

Applications

  • Moulded parts or profiles subjected to repeated stress, O-rings, damping systems.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • NF ISO 815
  • ISO 3302 (M2/E1/L2)

Series 14 – Enhanced peroxide silicone for steam and fluid resistance

Series 14 is a peroxide-cured silicone compound formulated specifically to improve resistance to water steam, coolant fluids and oils. It is processable by extrusion and moulding. It delivers good compression set properties, making it ideal for autoclave gaskets and applications in hot, humid environments where other silicones may degrade faster.

Shore A hardness60 – 70
Temperature range-60 °C / 200 °C
Density (g/cm³)1.16 – 1.20
Tensile strength (MPa)8.0 – 8.0
Elongation at break (%)300 – 360
Tear strength (kN/m)15.0 – 18.0
Curing systemPeroxide
Processing methodExtrusion and Moulding
Base colourNatural / RAL colours
Available coloursRAL colours on request

Applications

  • Autoclave gaskets, parts in contact with steam or coolants.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • BfR IX and XV
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 22 – Peroxide silicone resistant to steam and aromatic oils

Series 22 is a peroxide-cured silicone compound processable by extrusion and moulding. It is characterised by good stability against water steam and resistance to certain aromatic oils (at low dosages). Unlike other standard series, its base colour is RAL 1013 (Translucent). It is a technical solution suitable for autoclave gaskets, moulded parts and O-rings exposed to mixed conditions of temperature and specific fluids.

Peroxide-cured silicone with good stability against steam and aromatic oils in low concentration. Processable by extrusion and moulding.

Shore A hardness40 – 80
Temperature range-60 °C / 200 °C
Density (g/cm³)1.11 – 1.36
Tensile strength (MPa)6.4 – 7.9
Elongation at break (%)130 – 390
Tear strength (kN/m)9.5 – 14.0
Curing systemPeroxide
Processing methodExtrusion and Moulding
Base colourRAL1013 Translucent

Applications

  • Autoclave gaskets, moulded parts, O-rings.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • RoHS compliant
  • REACH compliant

Series 9 – Peroxide-cure silicone with excellent thermal resistance (300°C)

Series 9 is a peroxide-cured silicone compound formulated specifically to deliver excellent thermal stability. It is processable by extrusion and moulding. Its main feature is the ability to operate across a wide temperature range, withstanding from -60°C to +300°C in continuous service, with short peaks up to 315°C. It is the ideal material for oven equipment and industrial applications with high thermal demands.

Peroxide-cured silicone with excellent thermal resistance, suitable for continuous use up to +300 °C and short peaks of +315 °C. Offers strong mechanical properties and stability across a wide temperature range (-60 °C to +300 °C). Recommended for oven applications, profiles and moulded parts subjected to high temperatures.

Shore A hardness40 – 68
Temperature range-60 °C / 300 °C
Peak temperature315 °C
Density (g/cm³)1.11 – 1.20
Tensile strength (MPa)6.0 – 8.0
Elongation at break (%)300 – 400
Tear strength (kN/m)12.0 – 17.0
Curing systemPeroxide
Processing methodExtrusion and Moulding
Base colourNatural / Transparent
Available coloursRAL colours on request

Applications

  • Profiles, industrial oven equipment, moulded parts and extreme thermal applications.

Certifications and technical standards

  • FDA 21 CFR §177.2600
  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 16 – Fire-retardant self-extinguishing peroxide silicone (EN 45545-2) PMQ

Series 16 is a peroxide-catalysed silicone blend, processable by extrusion and moulding, designed specifically to provide excellent fire resistance and self-extinguishing properties. It complies with railway standard EN 45545-2 version 2020 (Requirements R22 and R23, levels HL1, HL2 and HL3), which makes it the ideal choice for sealing gaskets, profiles and parts in environments where fire safety is critical.

Peroxide-catalysed technical silicone with fire-retardant formulation optimised for the railway sector. It complies with R22/R23 requirements of EN 45545-2:2020 (HL1, HL2, HL3). Processable by extrusion, it offers high thermal resistance, mechanical stability and low emission of smoke and toxic gases.

Shore A hardness30 – 85
Temperature range-60 °C / 200 °C
Density (g/cm³)1.09 – 1.26
Tensile strength (MPa)5.0 – 9.0
Elongation at break (%)380 – 850
Tear strength (kN/m)17.0 – 25.0
Oxygen index (LOI)32.7
Smoke density (Ds max)84.7
ITC / Hazard Level0.06
Railway hazard levelHL1, HL2, HL3
Catalysis typePeroxide
Processing methodExtrusion and moulding
Base colourBlack / Blue-black (RAL 9017 / RAL 5004)
Available coloursBlack (RAL 9017), Blue-black (RAL 5004)

Applications

  • Railway applications (seals, profiles, gaskets, thermal protections, insulation panels).

Certifications and technical standards

  • EN 45545-2 R22/R23 HL1-HL2-HL3
  • RoHS compliant
  • REACH compliant
  • NF EN 45545-2:2020
  • EN ISO 4589-2 (O₂ Index 32.7%)
  • EN ISO 5659-2 (Ds max 84.7)
  • EN 17084 (ITC PNL 0.06)

Series 13 – Fluorosilicone (FVMQ) with high resistance to oils and solvents

Series 13 is a fluorosilicone blend (FVMQ base) catalysed with peroxide, designed specifically to provide exceptional resistance to mineral oils, fuels and organic solvents. It is processable by extrusion and moulding. Its main feature is its ability to retain its properties in environments where standard silicones (VMQ) would degrade or swell, making it ideal for applications in contact with aggressive fluids.

Fluorosilicone (FVMQ) catalysed with peroxide, processable by extrusion and moulding. It combines good mechanical properties with excellent resistance to oils, fuels and organic solvents. Designed for aggressive environments, with a thermal range from -60 °C to +170 °C (up to +220 °C with thermal additive).

Shore A hardness40 – 70
Temperature range-60 °C / 170 °C
Density (g/cm³)1.40 – 1.46
Tensile strength (MPa)6.0 – 7.0
Elongation at break (%)160 – 400
Tear strength (kN/m)10.0 – 21.0
Catalysis typePeroxide
Processing methodExtrusion and moulding
Base colourNatural / Transparent
Available coloursRAL colours on request

Applications

  • Profiles, moulded parts and special components for environments with oils or solvents.

Certifications and technical standards

  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/E1/L2)

Series 11 – Peroxide-cure electroconductive silicone

Series 11 is a peroxide-catalysed silicone blend with electroconductive properties. It is processable primarily by moulding (extrusion possible subject to evaluation). Its specific formulation gives it low resistivity, making it ideal for the management of electrical charges, wiring equipment, connectors and electromagnetic shielding (EMI/RFI).

Electrically conductive technical silicone catalysed with peroxide, developed for electrical and connector applications. It offers low resistivity, good thermal stability (-50 °C to +210 °C) and good mechanical strength, available only in black. Processable primarily by moulding and, subject to evaluation, by extrusion.

Shore A hardness50 – 70
Temperature range-50 °C / 210 °C
Density (g/cm³)1.11 – 1.16
Tensile strength (MPa)5.0 – 5.0
Elongation at break (%)100 – 250
Tear strength (kN/m)5.0 – 10.0
Catalysis typePeroxide
Processing methodMoulding (extrusion subject to evaluation)
Base colourBlack
Available coloursBlack only

Applications

  • Wiring equipment, connectors, moulded parts and components with electrical conductivity.

Certifications and technical standards

  • RoHS compliant
  • REACH compliant
  • NF ISO 7619-1
  • NF ISO 37
  • NF ISO 34-1
  • NF ISO 2781
  • ISO 3302 (M2/L2)
ISO 8 cleanroom · Italy · Top Tech

Plastic-silicone 2K two-shot press in ISO 8 cleanroom: a single injection cycle, no intermediate handling

The ISO 8 cleanroom at Top Tech Silicones (Italy · ISO 14644-1) integrates the fleet of 6 electrically driven 100 % silicone LSR presses, one plastic-silicone two-shot press and one plastic press dedicated to producing the plastic supports that are then overmoulded with silicone. Quality system with process FMEA, R&R, DOE and IQ/OQ/PQ.

The 2K two-shot press injects the thermoplastic and the silicone consecutively in the same mould, without the part leaving the enclosure between the two injections. The sterility chain is preserved from start to finish: critical for Class I and IIa medical devices, direct food contact and applications sensitive to cross-contamination between the two materials.

Each batch produced in the cleanroom is supplied with a certificate of conformity, process parameter logs (injection pressure and temperature, cure time) and full raw material traceability — plastic insert and silicone — to feed the customer's technical file or regulatory validation dossier.

Services and processes

Moulding processes of the group

Catalogue

Related products for overmoulding

Need plastic-silicone overmoulded parts?

Send us the drawing of the insert and of the finished part (STEP, IGES or PDF), the insert material (metal or thermoplastic), the applicable silicone series or end-use sector, the required standards (FDA, USP VI, ISO 10993, EN 45545-2…) and the annual volume. We will confirm whether the part fits 2K two-shot (Italy, Top Tech) or conventional overmoulding (France, Progress) and provide a quote with the tooling lead time.