COPSIL3D, a 3D printable silicone suitable for skin contact

COP Chimie is a French SME based in the Vercors region which has been developing materials for the orthopedic industry for over 30 years. The company’s Research and Development laboratory, as well as its synthesis unit, has succeeded in developing COPSIL3D 4025, a printable silicone elastomer certified for skin contact. This new soft and flexible material makes it possible to produce orthoses and external prostheses by 3D printing. Such an innovative solution in the field of orthopedic devices allows for faster manufacturing of custom-made medical devices and will greatly facilitate the life of many disabled people who wear these devices on a daily basis.

Benefits of silicone 3D printing

Silicones, generally in the form of oils or translucent elastomers that can be easily colored, are appreciated for their resistance to temperature, their flexibility, their hydrophobic and texturing character. Silicones also ensure chemical stability, which makes them suitable for the physiological environment in particular. Thus, silicones are used in the composition of numerous products and objects with a wide range of uses: hygiene and cleaning products, seals, industrial or food molds, coatings and paints, lubricants and greases, prostheses, toys, etc.

In the medical field, for example, additive manufacturing of silicone makes it possible to produce custom-made devices without the need for manual impressions or molding, thus reducing manufacturing time and costs. It also makes it possible to include voids and to vary the filling rate of structures to lighten them or modify their properties, for example:

• lower the hardness
• increase resilience
• allow for better damping
• add anisotropy to the printed object
• increase the mechanical properties
• increase exchange surfaces

COPSIL3D, the printable RTV silicone for skin contact

Supported by thesis work in partnership with IMP/INSA in Lyon, COP has developed a silicone with a specific consistency that allows layer by layer deposition of liquid silicone without collapse. The hardness and reactivity of COPSIL3D can be adapted to the type of structure to be built. The cross-linking (the curing of the elastomer), catalyzed by platinum, takes place at room temperature once the two parts have been mixed in the static mixer at the print head. It can be accelerated by the addition of energy.

Printed COPSIL3D elastomers have the same mechanical properties as cast silicone, with no shrinkage or odor, and are compatible with skin contact applications (ISO 10993-5 certification). They are ideal for the manufacture of flexible parts with complex designs or small series, for example for prototyping.

In order to democratize this technology, COP Chimie is partnering with F3DF, French specialists in online 3D printing courses, to offer training on 3D printing of silicones.