Wacker Chemie AG is presenting new silicone rubber grades that do not need to be post-cured after processing at Fakuma 2023. Elastosil LR 5003 liquid silicone rubber is suitable for applications in the food industry and other sensitive areas and does not require post-curing to comply with regulatory limits.

Wacker is also presenting a novel solution for marking silicone rubber. Elastosil color pastes ensure that such silicones can be permanently and precisely labeled by laser. The spotlight is also trained on Elastosil eco. These silicone rubber grades are manufactured in a resource-efficient manner using non-fossil methanol.

Silicone rubber frequently undergoes post-curing after processing. During this post-curing procedure, the cured silicone elastomer is heated in a well-ventilated oven for several hours to temperatures of up to 200 degrees Celsius. This eliminates volatile components while enhancing the strength of the silicone rubber. However, this is an expensive step in production that not only consumes a lot of time and energy, but also interrupts the flow of a highly automated production process.

Elastosil LR 5003 complements Elastosil LR 5040, which is also a non post-curing liquid silicone rubber. Even without post-curing, the latter exhibits a high degree of tear resistance, a property required for, for example, drinking and soothing teats, teething rings and other babycare articles that have to withstand high mechanical stresses.

Wacker now also solved this problem. With Elastosil Color Pastes Laser Marking, the group has developed a product that allows for the permanent labeling of silicone elastomers using lasers. The pastes contain laser-sensitive pigments which, when exposed to laser light at a wavelength of 1064 nanometers, very precisely either change their color or cause the elastomer to foam. This creates a permanent, non-washable mark inside or on the surface of the product. This marking is resistant to heat, sunlight and UV light. Marking is contactless – either as a separate marking step after production or during the production process.