Hull classes in compact regular frames

KReg is the category of compact regular frames and frame homomorphisms. A class of KReg frames H is a hull class provided that: (i) H is closed under isomorphic copies; (ii) for every F∈KReg there exist an hF∈H and a morphism h_F such that F≤h_FhF is essential; (iii) if F≤ϕH is essential and H∈H, then there exists hϕ:hF⟶H for which ϕ=hϕ·h_F. This work provides techniques for identifying and generating hull classes in KReg. Moreover, for a compact regular frame F, we introduce and investigate various properties of projectability and disconnectivity of F and prove that for each property, P, the class of KReg-objects that satisfy P is a hull class in KReg. In addition, we provide examples of KReg hull classes that are not characterized by some form of projectability/disconnectivity and examples of classes of KReg-objects that are not hull classes.