  We investigate a class of nonlocal integro-differential equations involving
Hilfer fractional derivatives and almost sectorial operators. We prove
existence results by applying Schauder's fixed point technique. Moreover, we
show fundamental properties of the solution representation by discussing two
cases related to the associated semigroup. For that, we consider compactness
and noncompactness properties, respectively. Furthermore, an example is given
to illustrate the obtained theory.
