Techsil® RTV27941 is a translucent liquid silicone rubber designed with mould making in mind. When mixed this two-part casting resin kit cures at room temperature to a flexible 41 Shore A translucent silicone rubber with a linear shrinkage of just 0.1%.

A Durable Mould Making Rubber

As a mould, RTV27941 offers excellent release ability with fantastic durability when used with both epoxy and polyurethane resins. These properties are due to its high tear (620 N/mm) and tensile (6.4 MPa) strength, along with elongation of 360%!

Resistance to tear is a very important feature for any moulding rubber, once cured it enables the mould to be stretched and pulled in various directions and still retain its original shape. This is key when removing the cast parts from the mould and will ensure a longer usable life for the mould itself.

RTV27941 is perfect for prototype mould making across a range of industries; favoured in the electronics industry for making home appliance moulds, along with TV’s, mobile phones and copy machines. In the Automotive Industry, RTV27941 is proving popular for creating console box moulds, radiator grills and lamp housings.

With a handy mix ratio of 10:1 and a low working viscosity, RTV27941 is very easy to use. It offers a work life of 90 minutes at room temperature and a full de-mould time of 24 hours. To achieve faster cure speeds, elevated temperatures may be used. 

Available in a range of different sized kits to suit any requirement, the most popular kit sizes are 1.1kg and 5.5kg. Both are available online with next working day delivery.

Benefits of Using a Translucent Mould

The ability to create accurate prototype parts in a fast and cost efficient way is a key element in today's Rapid Prototyping Industry. Silicone resin systems designed for mould making, coupled with quick curing injectable resins work together to create an ideal solution to meet these demanding criteria, using a translucent silicone in this process brings added benefits.

When making a mould with translucent material there is no concern over how the master is encased, it can be completely enclosed and covered with the silicone as the translucency provides an optical aid which allows the master to be easily cut out using a knife. The mould can then be re-assembled and resin injected to re-create the original, at this stage the translucent mould provides a visual check to ensure the resin has been effectively injected.

Techsil® Can Help

Techsil® supplies a large range of casting materials covering the full shore hardness spectrum. In addition there is a rainbow of pigment options available for both silicone and polyurethane casting resins. With highly regarded Technical Expertise in materials and dispensing, Techsil can take you from early design and prototyping, through to production and mass manufacture.   

For further Information, email our technical team on