KÖSTER CT 228 Flex is an advanced epoxy coating designed for protecting concrete and steel surfaces. When applying to vertical surfaces it is mixed with 6% KÖSTER KB-Pox Thickening Agent. It is ideal for use in industrial and agricultural settings, such as wastewater treatment and biogas plants, and is also highly effective for safeguarding heavily loaded industrial floors. When higher slip resistance beyond R9 is necessary, KÖSTER CT 228 Flex can be textured with kiln-dried broadcast materials or used as a scratch coat by incorporating kiln-dried fillers. Additionally, it serves as a chemically and mechanically resilient top sealer for epoxy resin compounds or as a top coat for thick-layer surface protection in high-traffic areas.
For concrete substrates the surface must be dry, clean, and free from loose particles. Preparation involves mechanical methods such as shot blasting or grinding, followed by vacuuming to ensure a dust-free surface. Any significant surface roughness can be treated with a scratch coat primer or an epoxy resin screed, using products such as KÖSTER CT 121 or KÖSTER leveling compounds (e.g. KÖSTER SL Protect, KÖSTER SL Premium, or KÖSTER SL Flex). Cracks in the concrete should be sealed with KÖSTER KB-Pox IN and broadcast with kiln dried quartz sand as needed. For wall areas, sandblasting is recommended to achieve a rough, clean surface. A single layer of KÖSTER CT 228 Flex is applied.
For steel substrates the surfaces must be dry, clean, and free of oil and grease. Preparation should meet DIN ISO 12944-4 standards, with blasting to at least SA 2 ½ purity and a mean roughness of at least 50 μm, or manually with a steel brush to SA 3. Weld beads and seams must be removed, and edges smoothed by grinding. Optionally revisions can be made with KÖSTER CT 228 Flex, again incorporating 6% KÖSTER KB-Pox Thickening Agent. Finally, all dust and residues must be thoroughly removed to ensure a clean surface ready for coating. Two layers of KÖSTER CT 228 Flex are applied to ensure optimal protection.
