The Darex WBC 711 is said to offer a reduction of greenhouse gas protocol emissions by more than 30% compared to the established compound Darex OP 2928, excluding the use phase and end of life emissions. This calculation is based on Henkel Cradle-to-Gate Product Carbon Footprint assessment as defined in ISO 14067.
Sealing tinplate or aluminium cans with rectangular and oval ends, known in the industry as irregular ends, is challenging. Unlike in the case of round ends, the product cannot be evenly distributed around the end perimeter by centrifugal force. To date, Henkel's established compounds Darex OP 2928, Darex OP 453 and Darex OP 53BX have been available for shower head and die lining application. During the process, non-web additives must be added to avoid specific application problems. These include webbing and cloudy, elongated compound droplets known as angel hair. With the new development of Darex WBC 711, Henkel has eliminated the need for these additives, resulting in an effective conventional sealing at a lower applied cost. The water-based sealant is claimed to offer a cost-effective alternative for the same application, even enabling a higher throughput.
According to Henkel, material costs are reduced because the user no longer must purchase the additives previously required. In addition, the downtimes for additional cleaning of the application surfaces and the entire effort for the addition and mixing of the additive are eliminated. There is less end spoilage and sealant waste because the sealant can be applied more cleanly. The improved storage stability of the product is expected to result in an improved pot life. This leads to a reduction in metal waste since the nozzles clog less easily, preventing quality defects such as gaps in the seal and leaks that lead to rejection of the can end.
The sealant can be used in hot and cold filling, double seaming with or without steam injection, and in subsequent pasteurisation or sterilisation. DAREX WBC 711 is expected to improve operations for users of older generation liners because it was developed specifically for traditional shower head and die lining applications. The product is said to exhibit good resistance to hot oil and water and conforms with European food legislation as well as Food and Drug Administration (FDA) 175.300 requirements.
