Delta 20

Delta 20 is a retarder specifically developed for highly reactive cementitious binders and mortars. It has been specially formulated to retard the extremely fast setting times of Amorphous Calcium Aluminate (ACA)-based mixes, such as those based on Calumex® SC-A and Calumex® XT-20, without sacrificing performance in areas like strength development and rapid hardening. This provides improved workability combined with rapid hardening.

• Specifically designed for fast-setting systems
• Accurate adjustment of setting times
• Little to no loss in strength development
• Fine powder that quickly dissolves in slurry
• Can be added to dry mortar mix to improve characteristics
• Specially formulated for ACA-based systems
• Low dosage
• Improved workability

At a dosage of 0.3%, the initial setting times of Calumex® SC-A (mixed with Portland cement at a 1:9 ratio) can be increased from 30 seconds to over 10 minutes. Importantly, the final set will remain within 1 minute of the initial set, retaining the Amorphous Calcium Aluminate’s critical characteristics.

When used with Calumex® XT-20, Delta 20 extends workability even further while maintaining performance characteristics, opening a range of new possible applications for ACA-based mixes.

The setting behavior demonstrates that Delta 20 significantly increases the open time for both Calumex® SC-A and Calumex® XT-20 while retaining rapid hardening after the initial set. Dosages of 0.3% and 0.5% are shown to provide varying levels of retardation, suitable for different applications.

The required dosage will vary depending on factors such as the type of cement used, the ratio at which SC-A or XT-20 is added, and the applied water-cement factor. Always carefully test the required dosage in any formulation to ensure optimal performance.