As one of the chemical companies with the most R&D investment in the world, Wacker Chemie AG demonstrated the new silicone rubber products without secondary vulcanization after being processed at this Fakuma Exhibition (held in Frederick, Germany, from October 17 to 21). In addition, a new silicone elastomer marking solution has been introduced: it can ensure that the laser can accurately and permanently mark such silicone.
01 Silicone rubber without secondary vulcanization
ELASTOSIL®LR 5003
Many silicone rubbers are cured at constant temperature after their processing. At this time, it is necessary to heat the cured silicone elastomer for several hours at a temperature of 200 ℃ in a well ventilated furnace to remove volatile components and improve the strength of silicone rubber. This is an expensive production process, which not only requires a lot of time and energy, but also the highly automated production process must be interrupted.
Wacker now uses elastosil®LR 5003 that has developed a series of non isothermal curing silicone rubber products, which are especially suitable for mass production in food and other sensitive applications. In terms of the content of volatile components, the molds made of these organosilicon can meet the limit value requirements of the German Federal Institute for Risk assessment (BFR) without secondary vulcanization, and can meet the requirements of the U.S. Food and Drug Administration (FDA) for food contact products.
This means that the production of reusable straws, baking molds, dough scrapers and other items can now become extremely efficient. The manufacturer can also provide that elastosil® LR 5003 is subject to secondary vulcanization to further improve the strength of the product and reduce the volatile content.
Elastosil® LR 5003 is the elastosil of liquid silicone rubber without constant temperature curing treatment® Expansion of LR 5040 series. The latter has high tear strength without secondary vulcanization. It is an ideal material for bottled nipples, pacifiers, rubber rings and other baby care products that must withstand strength wear.
02 Pigment paste capable of permanently marking silicone elastomer
Elastosil® Laser marking
Many applications, such as the classification of cables or hoses used in the medical field, or the tracking of production series and batches, require the permanent marking of silicone. However, when silicone rubber is marked, the traditional printing process will soon reach its limit, and the marking handwriting will often be worn or blurred.
Wacker introduces elastosil, a product that can permanently mark silicone elastomers with the help of laser®Laser marking pigment paste. These pigment pastes contain laser sensitive pigments, which can change the color under the laser irradiation with the wavelength of 1064 nm, or make the elastomer bubble accurately, leaving permanent marks that cannot be cleaned inside or on the surface of the product. These markings are heat resistant, sunlight resistant, and UV resistant. This non-contact marking can be completed after the end of production or during the production process.
In order to ensure ideal readability on different colors of silicone rubber, Wacker provides three easy-to-use masterbatches for laser marking of liquid and solid silicone rubber:
l Elastosil® Color paste laser marking white: it can be used to print white marks on dark substrates;
l Elastosil® Color paste laser marking Black: it can be used to print black marks on light colored substrates;
l Elastosil® Color paste laser marking black TRL: it can be used to print transparent substrates.
In addition to the above two new products, elastosil®Eco is also the highlight of the Wacker booth. These silicone rubbers are produced with non Petrochemical bio based methanol as raw material by certified process in a resource-saving way, which not only saves production time, but also reduces production cost.
