What is liquid silicone rubber LSR? Liquid silicone rubber (LSR) is a liquid two-component material for injection moulding precision parts. For solid, malleable grades, we use HTV , which falls under High Consistency Rubber (HCR) . This page explains when to choose silicone rubber for casting and when platinum-cured silicone...
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High temperature vulcanising silicone rubber is an addition-curing silicone. These silicones are ideal for processing with a press at elevated temperatures in stainless steel or aluminum molds. These silicones are available in many variations and are (partly) customer-specific. We have...
Liquid silicone rubber is a form of addition-curing silicone. These silicones are ideal for processing with an injection machine in stainless steel or aluminum molds. These silicones are available in many variations and are (partly) customer-specific. We have more than...
What is liquid silicone rubber LSR?
Liquidsilicone rubber (LSR) is a liquid two-component material for injection moulding precision parts.
For solid, malleable grades, we use HTV , which falls under High Consistency Rubber (HCR) . This page explains when to choose silicone rubber for casting and when platinum-cured silicone offers the best performance.
LSR advantages: High reproducibility, fine details, short cycle times and excellent resistance in demanding applications (medical, food-contact* and precision components).
*Use only grades explicitly released for food contact and follow the datasheet instructions.
LSR properties
✓2-component mixing in the machine, low viscosity
✓Stable properties over a wide temperature range
✓Mass production suitable for complex geometries
✓High dimensional stability and reproducibility
HTV/HCR properties
→Solid compound suitable for compression/transfer/extrusion
→High tear resistance and long-term mechanical stability
→Widely applicable in industry, automotive and electrical insulation
Silicone rubber casting: when to choose RTV-2?
RTV-2 benefits
For prototyping, molds and smaller series , RTV-2 silicone rubber is suitable: two-part systems that cure at room temperature.
Excellent detail capture for molds and models
Choice of soft to firm hardness (Shore A-range)
Compatible with epoxy/PU/polyester
Platinum-cured silicone
Platinum-cured silicone (addition) offers low shrinkage, high dimensional stability and consistent mechanical properties.
Very low shrinkage and stable properties over time
Suitable for high-quality molds and end parts.
Widely applicable from SFX/lifecasting to technical components
Applications of liquid silicone rubber
Together, LSR and HTV/HCR cover a wide range of applications: from seals and dampers to medical, culinary, and electronic components.
Common applications
→ Gaskets, O-rings and seals with tight tolerances
→ Electrical/electronic components and insulation
→ Medical and (select) food-contact parts*
→ Molds, prototypes and small series production (RTV-2)
*Use only certified grades; follow datasheets and regulations.
Processing and advice
LSR injection molding
Correct mixing and dosing settings, mold conditions and venting are crucial.
HTV/HCR molding
Match compound temperature, cure system (peroxide/platinum) and pressure/time.
RTV-2 casting
Precise weighing, homogeneous mixing, deaerating or pouring in a thin stream.
Frequently Asked Questions (FAQ)
What is the difference between LSR and HTV High Consistency Rubber?
LSR is a liquid and is processed via injection molding; HTV/HCR is a solid compound for compression/transfer molding. LSR is ideal for complex shapes and series production; HTV/HCR for robust parts and high mechanical requirements.
When should I choose platinum-cured silicone over RTV-2?
Use platinum-cured silicone when low shrinkage, odor/evaporation, and dimensional stability are crucial (medical/food contact, precision). RTV-2 is the preferred choice for molds/prototypes where detail and flexibility are important and room-temperature curing is desired.
Can I cast silicone rubber with epoxy, PU or polyester?
Yes. Use the correct release agent for each system, see porous masters, and follow the product instructions. Always test a small area first on critical components.
Liquid silicone rubber uses: what are the main applications?
Gaskets/seals, medical and (select) food-contact parts, damping elements, electronic components, and precision parts with fine details. For molds and prototypes, RTV-2 is an efficient choice.
Need advice or a quote?
We supply LSR and HTV/HCR materials from renowned brands and can formulate specific recipes upon request. Contact us for material selection, mold advice, or sample runs.
