WACKER Presents High-Density HDK^® Grade for Pharmaceutical Applications

WACKER showcased its pyrogenic silica grade HDK^® N20P Pharma for the first time at the CPhI Worldwide 2019 pharmaceutical tradeshow in Frankfurt at the end of last year. The product is designed as an excipient for pharmaceutical applications. Even in low amounts, it improves the flow characteristics of powder blends, absorbs moisture from hygroscopic solids and serves as a tablet disintegrant. A special feature of the new grade is its high tap density, which provides tangible logistics and handling benefits for pharmaceutical manufacturers.

The new product is a compressed version of the HDK^® N20 Pharma grade, which has been proving its merit as an excipient in the pharmaceutical industry for years. Both grades are hydrophilic pyrogenic silicas; their surfaces are thus wettable by water. Apart from the tap density, they possess the same physical-chemical properties. With a silicon-dioxide content of at least 99.8 percent, both products are highly pure and meet the specifications of the European pharmacopoeia and its US counterpart. Pyrogenic silicas are bulky white powders. In the manufacture of the new HDK^® grade, the flame process used for making the pyrogenic silica is followed by a compression step. At approximately 100 grams per liter, HDK^® N20P Pharma achieves a tap density that is slightly more than double that of its uncompressed counterpart.

The high degree of compaction has a positive effect on logistics and handling of the product. The media used to transport HDK^® N20P Pharma can now be filled with twice the amount of product. This halves the number of bags to be transported and thus the packaging volume. What’s more, the packaging-material savings reduce environmental pollution. There is also significantly less dust produced when the bags are emptied and the compressed pyrogenic silica is processed. Correspondingly less cleaning is required. In addition, the product is easier to meter due to its compactness.

HDK^® N20P Pharma is used as a processing auxiliary to improve processing of pharmaceutical powders, pellets and tablets. It also accelerates tablet disintegration. Amounts of less than 1 percent are typically sufficient in order to achieve these effects.