“What problems keep you up at night?” A simple question to formulators that revealed unmet needs in today’s industrial floor coatings: – “I need to reduce my floor system cost … I want coatings with improved robustness under adverse cure condition. And, I also need good aesthetics and an epoxy system that meets stringent VOC/emission requirements.”
In the application of epoxy industry floors, a maximum of four hours is acceptable to wait in between applying the primer and the topcoat, irrespective of cure conditions. Customers confirmed: “Anything longer than four hours and we have to send the application team home, only to come back the next day again.” Challenging targets. Especially given the fact that fast-cure epoxy systems require 8-12 hours at low temperature cure (10°C) before receiving a second coat and generally these systems suffer from carbamation.
Evonik answers these unmet needs with the commercialization of ANQUAMINE® 728 curing agent. This new product is a waterborne amine curing agent that offers fast cure and good aesthetics, for use in epoxy primers and topcoats on concrete substrates. Combined with ANCAREZ® AR-555 solid epoxy resin dispersion, ANQUAMINE® 728 curing agent yields a primer with recoat times of less than four hours at 10 °C and excellent adhesion to damp concrete. Topcoats are best formulated with diluted liquid epoxy resins for excellent aesthetics and good compatibility with pigment pastes. ANQUAMINE® 728-based coatings have a low tendency to carbamation and waterspotting and are applicable up to 500 g/m² (20 mils) wet film thickness. Two coats per day and next day back-in-service enables applicators to improve productivity and save cost/m2. The end-user receives a floor system that comes with excellent aesthetics and has potential to meet stringent emission requirements. That’s Cure-2-Go with ANQUAMINE® 728!
Figure 1: Recoat time of epoxy coatings to damp concrete at low temperature cure condition. Comparison of ANQUAMINE® 728 (Anq 728) versus a fast-cure Mannich base epoxy system.
Figure 2: Comparison of Delta-E as a function of hours of UV-A exposure: White epoxy coating based on ANQUAMINE® 728 versus an equivalent coatings based on solvent-free epoxy technology.