To learn more about how the chemical and physical properties of the CA binder influence the dissolution inhibition caused by the acids, we investigated the impact of HCl on the dissolution of four different calcium-aluminate binders. We used two commercial CA-cements and a pure CA phase. An additional cement was prepared by mixing CAC1 and pure CA in a 1:1 ratio, called 'CAC1/CA-Mix'. The physical properties (phase contents, Blaine surface area) and chemical properties of the mix are between those of the CACs and the pure phase (see Table ). For each binder, we measured the pH development for different HCl concentrations (see Figures ). Analogous to section 3.2, we extract the time to pH 9, which corresponds to the inhibition time of the initial CA-dissolution (see section 3.1). Again, we can describe the relation between the inhibition time and the amount of added protons for each binder/HCl combination with an exponential fit of the form t pH 9 = a • exp b[HCl] (see Figure ).