Remix each of the two components (part A and B) every time before using.

1. Mixing the two components

The components A and B are mixed by weight in the above indicated ratio. The mixing can be carried out either by hand or by using a low-speed electric or pneumatic mixer to minimise the introduction of air and to avoid any temperature increase.

It is also possible to use a special mixing and dispensing machine for the two silicone components. Further information is available upon request.

2. Degassing

The mixture should be degassed preferably at 30 to 50 mbar to eliminate any entrapped air. If a dispensing machine is used, the two components are degassed separately prior to mixing.

The silicone mixture expands to 3 to 4 times of its initial volume and bubbles rise to the surface. Wait a few minutes to complete the degassing and then release the vacuum. The silicone is ready for pouring, either by gravity or under low pressure.

Note: Release the vacuum once or twice accelerates the degassing. It is recommended to use a container with a high diameter / height ratio.

3. Polymerisation

The system polymerises at 23°C. The curing may be slowed down at lower temperature or accelerated by heat.

Contact with certain materials can inhibit the crosslinking. See list below:

  • Natural rubbers vulcanised with sulphur.

  • RTV 2 silicone elastomers catalysed with metal salts, e.g. tin-compounds.

  • PVC stabilised with tin salts and additives.

  • Epoxy resins catalysed with amines.

In case of doubts, it is recommended to test the substrate by applying a small quantity of the mixed silicone on a restricted area.

When stored in its original packaging at a temperature of between -10°C and +30°C, SILBIONE RTV 4420 A&B may be stored for up to 6 months from its date of manufacture.

Comply with the storage instructions and expiry date marked on the packaging.

Beyond this date, Bluestar Silicones no longer guarantees that the product meets the sales specifications.

Please consult the Safety Data Sheet of this product.Healthcare Class I;Skin Contact


SILBIONE RTV 4420 A&B is a two component silicone elastomer which cures at room temperature by a polyaddition reaction. The polymerisation can be accelerated by heat.

The silicone material is delivered as two low viscous liquid components, which once mixed and cured, transform into an elastic and resistant material. Polymerisation occurs without formation of heat.


2 Part RTV


Healthcare Class I;Skin Contact

  • Very high stretchability
  • Sterilisable
  • Fast mixing and easy processing due to low viscosity
  • Heel cushions
  • Toe separators
  • Liners for limb prostheses


Asia Pacific;Europe Middle East Africa;Central and South America;North America

For information about Storage and Shelf Life for this product, please download the Technical Data Sheet.




Viscosity3750PairedCompISO 2555mPa.s
ColorTranslucentPairedCompEuropean Pharmacopea




Viscosity3750PairedCompISO 2555mPa.s
ColorTranslucentPairedCompEuropean Pharmacopea






hardness_cd523e03-72a3-4261-93f9-36f7bbeeafb1hardness_cd523e03-72a3-4261-93f9-36f7bbeeafb1Hardness> 60PairedMix
elongation_68a5ddf2-2baf-4e60-ac6f-0a8a18a758b2elongation_68a5ddf2-2baf-4e60-ac6f-0a8a18a758b2Elongation> 400PairedMixDIN 53504%
pot-life_0d649a54-7503-4c7c-a047-9d0c4b3e9f6apot-life_0d649a54-7503-4c7c-a047-9d0c4b3e9f6aPot life50PairedMixmin
tear-strength_a14604f3-602f-4240-a9bf-15d90bbfbd13tear-strength_a14604f3-602f-4240-a9bf-15d90bbfbd13Tear strength> 10PairedMixDIN 53515N/mm





SILBIONE RTV 4420 BSILBIONE RTV 4420 B/our_offer/Product/90024832/90024831/SILBIONE-RTV-4420-B






















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